# Portable generator causing central AC compressor to run strange



## anthony21078

Hello Everyone...
I bought a Duromax xp12000eh portable generator (Rated Gas-9500w/Surge Gas-12000w, Rated Propane-9025w/Surge Propane-11400w) in hopes of running my entire house if needed. 50amp inlet box was installed and wired to the main panel with a 50amp breaker and interlock kit. Not using a transfer switch. Several weeks ago my son and I went through the house and each breaker with a clamp meter to measure amps. After yesterdays test run with the generator and testing numerous appliances at the same time, I am happy with the generator to power my home.

Now comes the central AC. It is a 5 ton Amana ASX16 single speed scroll compressor that was installed June 2018 with a Goodman air handler. Clamp meter read 49amps on start during my testing with a LRA rating of 135. I installed a 5-2-1 hardstart kit which brought the startup down to roughly 34amps.

I tested the AC by itself under generator power using propane with every other breaker off. The generator stumbled slightly once but recovered rather quickly. I noticed the AC compressor sounded different at startup and the fan had roughly a 2 second delay to start VS starting almost instantly while running off normal power. Also, while running on generator power, it appears the fan was not running at fun speed and there was a vibration coming from the unit that would cause the grate to make a noise. You can hear all this in the videos.

I read elsewhere about testing the frequency but unfortunately that was after the fact. Im not really sure where to start troubleshooting. I don't want to keep forcing the AC to start while using the generator to diagnose the problem if I am putting unnecessary stress/wear on the compressor and/or fan motor.

Generator Start





Normal Start


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## ToolLover

If I were you I would buy a frequency meter. (About $5 from Anazon) and set the speed to 60 Hertz.
You can install it permanently on the generator.
I put one on my Honda when I installed the NG-LP fuel supply.
You have to start some where and the meter is a begining.
Then one of the other guys may help you on the ailments of dirty power from the generator.


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## iowagold

you need a soft start unit. hard start helps a bit.. but the soft start is the way to go
EasyStart™ 368-X72 Soft Starter is the model number for the large air con unit.
it will support up to a 6 ton unit or 72k btu.
here is the link to the oem place to buy it direct from them








EasyStart™ 368 Soft Starter


The EasyStart™ soft start motor starter supports 115 & 230V A/C motors & employs a 4-part start ramp sequence that offers the lowest possible start-up current.




www.microair.net





EasyStart™ 368-X72 Soft Starter
they are pricy $338.00 usd plus shipping.
but they are the best in class.
they sure work right!!
you get what you pay for..
these help reduce the load even when on normal grid power as well.

most folks when the go to replace the old style ac units get an inverter ac unit.
they cool so much more for less power.
just saying if you do replace the compressor unit in the future upgrade it.


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## Melson

I'm wondering if something more problematic is at work?
Is that ac unit a variable speed or variable frequency type? If so you could be experiencing harmonics or more likely waveform distortion/ interactions/ feedback. An o-scope would show this but I realize that is not a common tool. 
You might also catch some waveform issues by looking at the a/c duty cycle; usually duty cycle is a software function of most decent dvm's. (Example on Fluke 189: set to ac; toggle "Hz % ms"; duty cycle is the % toggle).
Good luck.


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## anthony21078

ToolLover said:


> If I were you I would buy a frequency meter. (About $5 from Anazon) and set the speed to 60 Hertz.
> You can install it permanently on the generator.
> I put one on my Honda when I installed the NG-LP fuel supply.
> You have to start some where and the meter is a begining.
> Then one of the other guys may help you on the ailments of dirty power from the generator.


I have a Kill a Watt meter somewhere. Even though it only has a 120 outlet, Ill throw an extension cord on there and see what I get



iowagold said:


> you need a soft start unit. hard start helps a bit.. but the soft start is the way to go
> EasyStart™ 368-X72 Soft Starter is the model number for the large air con unit.
> it will support up to a 6 ton unit or 72k btu.
> here is the link to the oem place to buy it direct from them
> 
> 
> 
> 
> 
> 
> 
> 
> EasyStart™ 368 Soft Starter
> 
> 
> The EasyStart™ soft start motor starter supports 115 & 230V A/C motors & employs a 4-part start ramp sequence that offers the lowest possible start-up current.
> 
> 
> 
> 
> www.microair.net
> 
> 
> 
> 
> 
> EasyStart™ 368-X72 Soft Starter
> they are pricy $338.00 usd plus shipping.
> but they are the best in class.
> they sure work right!!
> you get what you pay for..
> these help reduce the load even when on normal grid power as well.
> 
> most folks when the go to replace the old style ac units get an inverter ac unit.
> they cool so much more for less power.
> just saying if you do replace the compressor unit in the future upgrade it.


I read quite a bit on the hard start VS soft start kits a while back. Went with the hard start first for the simple fact that it was 30$ vs 300$. I have no problem buying the soft start If i knew it would solve the issue at hand. Just trying to troubleshoot a little more at this point



Melson said:


> I'm wondering if something more problematic is at work?
> Is that ac unit a variable speed or variable frequency type? If so you could be experiencing harmonics or more likely waveform distortion/ interactions/ feedback. An o-scope would show this but I realize that is not a common tool.
> You might also catch some waveform issues by looking at the a/c duty cycle; usually duty cycle is a software function of most decent dvm's. (Example on Fluke 189: set to ac; toggle "Hz % ms"; duty cycle is the % toggle).
> Good luck.


The AC is a single speed rated at 60hz. Appreciate the info on the Fluke. It may be the tool I need to get. 
.
.
.

I'm trying to put in perspective the sequence of events that occur from switching on the AC, into the delayed start, then eventually starting. Lets see if this makes sense....

1)Generator is running with no load
2)AC is switched on
3)Generator bogs down/drops RPMs for 1 second and catches itself returning to normal speed
4)At the same time the generator bogs down, the AC compressor/fan turn attempt to turn on
5)Instead of the normal loud click from the compressor while using grid power and instantly turning on, there is 1 click, followed by a second click which then starts to spin the fan

So, is it more likely the generator is under-powered to handle the initial load and when the generator regains its normal operating speed that is the cause of that second click from the AC which then makes it start?

However, if that's the case why wouldn't the fan be operating at full speed?

Just thinking out loud here


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## drmerdp

I think its safe to say the generator is too small to start a 5 ton without a soft start. Even if the engine of the generator only momentarily bogs then recovers, the initial amp draw is likely causing too much voltage drop. The AVR will try to adjust back but it may not recover enough fast enough. Definitely confirm the frequency. The Hz is in direct correlation to engine speed. Low Hz will result in erratic voltages as the AVR struggles to maintain ~125 vac. I like to start at 62.5hz at no load then throw on the generators rated load (resistive) and look for no less then 58hz.

I remember reading somewhere that inductive loads run way more efficiently the cleaner the sine wave. The duromax likely has a quite a bit of THD. I'd love to see what the waveform looks like on an oscilloscope.

I'll be buying a soft start in a month or so. Going to run my 3.5 ton rheem with a scroll compressor off my Eu7000. Though I'm torn between the micro air and hyper engineering. Leaning toward the micro air, but its 60-70 bucks more.









Hyper Engineering SS1B16-32SN V230 Hyper Sure Start Single Phase Soft Starter 230V 16-32 FLA


Buy Hyper Engineering SS1B16-32SN V230 Direct. Free Shipping. Check the Hyper Sure Start Single Phase Soft Starter 230V (16-32 FLA) ratings before checking out.




www.electricgeneratorsdirect.com


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## anthony21078

drmerdp said:


> I think its safe to say the generator is too small to start a 5 ton without a soft start. Even if the engine of the generator only momentarily bogs then recovers, the initial amp draw is likely causing too much voltage drop. The AVR will try to adjust back but it may not recover enough fast enough. Definitely confirm the frequency. The Hz is in direct correlation to engine speed. Low Hz will result in erratic voltages as the AVR struggles to maintain ~125 vac. I like to start at 62.5hz at no load then throw on the generators rated load (resistive) and look for no less then 58hz.
> 
> I remember reading somewhere that inductive loads run way more efficiently the cleaner the sine wave. The duromax likely has a quite a bit of THD. I'd love to see what the waveform looks like on an oscilloscope.
> 
> I'll be buying a soft start in a month or so. Going to run my 3.5 ton rheem with a scroll compressor off my Eu7000. Though I'm torn between the micro air and hyper engineering. Leaning toward the micro air, but its 60-70 bucks more.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Hyper Engineering SS1B16-32SN V230 Hyper Sure Start Single Phase Soft Starter 230V 16-32 FLA
> 
> 
> Buy Hyper Engineering SS1B16-32SN V230 Direct. Free Shipping. Check the Hyper Sure Start Single Phase Soft Starter 230V (16-32 FLA) ratings before checking out.
> 
> 
> 
> 
> www.electricgeneratorsdirect.com


I tested the frequency with no load directly into the generator 120 outlet and also with a 100ft extension cord (if that matters). The frequency ranged from 62.2 - 62.9. No chance right now to shut off the main house breaker and try the AC at this moment. However, when I get the chance, will a frequency reading taken directly off the 120 generator outlet give me a correct reading when I attempt to start the AC? Or will measuring frequency at the AC itself with a clamp meter be the _more _accurate way?

"I think its safe to say the generator is too small to start a 5 ton without a soft start"....My gut is leaning towards this as well. 

I have seen in other generator manuals where the THD is actually listed. Unfortunately not in the Duromax manual. Ill have to call Monday


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## drmerdp

Doesn't matter where you get your frequency reading its all the same. Voltage on the other hand will differ based on gauge of wire, length of cable, and amps being drawn. 

Definitely report back the THD.


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## iowagold

hey ant what gauge of wire are you running from the gen to the house??
is it at least 6 gauge??

I think the micro air is better.. at least in the larger EasyStart™ 368-X72 Soft Starter units.
it is all voodoo lol!! or secret sauce stuff!!
chuckle..
we have been using the stuff from them for a while now and they work ok!!

those videos have a lot of noise for sure!! inductance to the shell steel!!
check the rubber isolators for the mounts on the fan and compressor..
is the fan cap bad?? just a question.. might be worth the 20 - 30 bucks to try another fan cap..
watch the ratings close.


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## anthony21078

iowagold said:


> hey ant what gauge of wire are you running from the gen to the house??
> is it at least 6 gauge??
> 
> I think the micro air is better.. at least in the larger EasyStart™ 368-X72 Soft Starter units.
> it is all voodoo lol!! or secret sauce stuff!!
> chuckle..
> we have been using the stuff from them for a while now and they work ok!!
> 
> those videos have a lot of noise for sure!! inductance to the shell steel!!
> check the rubber isolators for the mounts on the fan and compressor..
> is the fan cap bad?? just a question.. might be worth the 20 - 30 bucks to try another fan cap..
> watch the ratings close.


Im using the Conntek 1450ss2 50 amp 15ft cord which is 6 gauge. Also using 6 gauge from the inlet box to the main panel which is about 4ft.

Fan cap is good. I tested it when I installed the hard start several weeks ago. 

Testing to continue later today or tomorrow. Ill check those items you mentioned


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## Melson

I'm not familiar with that brand of generator but others have stated it doesn't provide the best electrical quality. That being said, we shouldn't point our finger at poor THD just yet; there's a lot of appliances out there that tolerate surprising electrical abuse and still perform.
So let's think about this.

From your description of engine sounds and the air cond contractor / relay noise we have a few clues:
-(clue) 'after one second it bogs then goes back to normal speed' = the engine is taking too long to react to a heavy load change.
-(assumption) If the air conditioner had tolerated the (generator's) voltage & frequency dip wouldn't that keep the engine staining under a heavy load? If we assume that then we would expect the engine to initially ' bog' but then recover only to some slightly higher rpm. But certainly it wouldn't return to a "normal" frequency, which I think you mentioned is 62.9 hz.
-(clue & guess) From the way the air conditioner is reacting (unusual "clicks; fan running slow) it seems that generator behavior is a real problem for the air conditioner's electronics (control board?).

At least you now know the engine isn't as robust as needed. Whether any further soft-start add-ons will help is impossible to say without looking at the air conditioner's SD and CD schematics (primarily), maybe the generator schematics (secondarily). If you can get a few diagnostic metrics (freq & voltage/time; waveform it would help point you in the right direction.


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## iowagold

anthony21078 said:


> Im using the Conntek 1450ss2 50 amp 15ft cord which is 6 gauge. Also using 6 gauge from the inlet box to the main panel which is about 4ft.
> 
> Fan cap is good. I tested it when I installed the hard start several weeks ago.
> 
> Testing to continue later today or tomorrow. Ill check those items you mentioned


ok cool on the cord and inlet, that should be good for 12kw.
yea I wish they made 75 amp inlet gear cheap...
I was looking for another project something hd...
looks like I will end up with the rv marine 50 amp 240/125 twist plugs and inlet..
they say 80% is the real rating.. so only 40 amps continues on a 50 amp plug cord setup..
ok on the wire for the short runs at 6 gauge.

if the math holds your should be 37.5 amps at rated 240vac.
hey I have a question!! and a idea??
is the outside fan motor 125 volt or 240 volt? 
and your inside fan motor is 125 volt..
if the out side fan motor is on lets say L1 and the inside furnace 125 volt electronics is also on L1
that could the it!! over load on one leg!!
this is why I do the fancy meter setup to watch the loads on L1 and L2.. see the below link





GENERATOR_CONNECTION


GENERATOR CONNECTION PANEL METER BREAKER INLET



www.poustusa.com





that makes it so you can see the real loads, the red and black switches indicate black as L1 red as L2 and are the meter on off switch, and the 1/4 amp fused green led's are for L1 and L2 grid indicator before the main breaker.
and the 3rd meter is for the 125 volt generator inlet at 60 amps for the eu2200i gens on natural gas.
I have links for the parts on the poustusa site.
I need to do a diagram as well..
lol been too busy.. GRIN!!
nice day out today!
lots done.
I also worked on the over night last night before the wind picked up.

I have been thinking of doing a you tube channel..
it takes lots of time to do a good repair video...
you can have 50 hours in production time for a 1/2 hour video..
now days with all the good computer gear it should take less if you had 5 cameras shooting all at once..
so much of this stuff is hands on...
easy to show you, but hard to explain how to!! GRIN!!


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## iowagold

oh yea are you running this on LP or gasoline during the testing???
what are your lp hose sizes?? as well as the couplings??
natural gas vapor hose needs to be 3/4...
and depending on where the regulators and the pressures on lp there are some size things on lp too!!
that affects the recovery on the gen set!!
try the testing on gasoline and see if it is ok!!
that might be an important issue..


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## Melson

I reread OP's first post and he stated "propane", which, as iowagold intimates, has a bunch of performance 'gotchas' you have to be aware of before it'll work out. 
Even if the generator was the gasoline fed variety it seems borderline for powering the OP's full household loads.


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## iowagold

yea I agree it is close on current.. I just thought if it was on gasoline that is the max output for the generator,
just for test..

I stand by my check on the L1 and L2 current on the fans on the hvac..
see if both the fans are on the same 125volt leg...
he can turn off the breakers for everything else in the house for the test only...
and see if it starts with just the furnace and the ac compressor..
I think the soft start will help on the heavy current run up..
then look at the current when running after the start...
I would build and put on the main breaker box the meter set like on this page





GENERATOR_CONNECTION


GENERATOR CONNECTION PANEL METER BREAKER INLET



www.poustusa.com




but set it for split phase or a meter for L1 and another meter for L2 on the generator input.
it will give you multi line data,


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## anthony21078

Melson said:


> I'm not familiar with that brand of generator but others have stated it doesn't provide the best electrical quality. That being said, we shouldn't point our finger at poor THD just yet; there's a lot of appliances out there that tolerate surprising electrical abuse and still perform.
> So let's think about this.
> 
> From your description of engine sounds and the air cond contractor / relay noise we have a few clues:
> -(clue) 'after one second it bogs then goes back to normal speed' = the engine is taking too long to react to a heavy load change.
> -(assumption) If the air conditioner had tolerated the (generator's) voltage & frequency dip wouldn't that keep the engine staining under a heavy load? If we assume that then we would expect the engine to initially ' bog' but then recover only to some slightly higher rpm. But certainly it wouldn't return to a "normal" frequency, which I think you mentioned is 62.9 hz.
> -(clue & guess) From the way the air conditioner is reacting (unusual "clicks; fan running slow) it seems that generator behavior is a real problem for the air conditioner's electronics (control board?).
> 
> At least you now know the engine isn't as robust as needed. Whether any further soft-start add-ons will help is impossible to say without looking at the air conditioner's SD and CD schematics (primarily), maybe the generator schematics (secondarily). If you can get a few diagnostic metrics (freq & voltage/time; waveform it would help point you in the right direction.


Manufacturer specs on the Duromax are 10-12% THD

My knowledge is limited in regards to reading schematics. If you care to thumb through those pages I can likely find them. Weather is nice today so I will hook the gen back up and get some numbers

My AC is model # ASX160601FC





Energy Efficient ASX16 Air Conditioner From Amana


Searching for an air conditioner that provides cooling w/out wasting energy? Contact Amana to learn more about the energy-efficient ASX16 Air Conditioner.



www.amana-hac.com
















iowagold said:


> if the math holds your should be 37.5 amps at rated 240vac.
> hey I have a question!! and a idea??
> is the outside fan motor 125 volt or 240 volt?
> and your inside fan motor is 125 volt..
> if the out side fan motor is on lets say L1 and the inside furnace 125 volt electronics is also on L1
> that could the it!! over load on one leg!!
> this is why I do the fancy meter setup to watch the loads on L1 and L2.. see the below link
> 
> 
> 
> 
> 
> GENERATOR_CONNECTION
> 
> 
> GENERATOR CONNECTION PANEL METER BREAKER INLET
> 
> 
> 
> www.poustusa.com
> 
> 
> 
> 
> 
> Im assuming the outside fan is 240. AC has a 50amp breaker
> Inside fan is 240. Air handler has a dual 20amp breaker. Pulls 6amps at start and 3amps running
> Im reading the spec sheet and the air handler has a has a "electronic blower time delay relay", that provides power to the blower motor with a delay of 7 seconds after voltage is applied. Wouldnt that delay negate the idea of overload?
> 
> Yes, I saw your meter setup and I like it. I will defineitly look into these parts


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## anthony21078

iowagold said:


> oh yea are you running this on LP or gasoline during the testing???
> what are your lp hose sizes?? as well as the couplings??
> natural gas vapor hose needs to be 3/4...
> and depending on where the regulators and the pressures on lp there are some size things on lp too!!
> that affects the recovery on the gen set!!
> try the testing on gasoline and see if it is ok!!
> that might be an important issue..


Propane was used for testing. For testing i was using a 3/8 house with 3/8 fittings that came with the generator. I used a 20lb bbq tank. I just installed the fittings to my 200lb tank with 1/2" 24 foot hose on order. I need 20 feet of length.

I thought about using gas. Gen specs state...
Gas - Rated 9500w
Gas - Surge 12000w
Propane - Rated 9025w
Propane - Surge 11400w

Wishful thinking but maybe that small amount of extra wattage on gas would rid the problem


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## Melson

@anthony21078: _"maybe that small amount of extra wattage on gas would ride the problem"..._

Perhaps. A bigger factor is that when running on gasoline you're more-or-less guaranteed a foolproof fueling system, which can be problematic for backyard mechanics to size for and pipe adequately for propane. In other words, there's more planning and upfront costs for propane vs gas.


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## tabora

anthony21078 said:


> ...My AC is model # ASX160601FC
> View attachment 7728


Wow, Locked Rotor Amperage is 135! That's a hefty startup load; likely too much for the "little" Duromax...


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## anthony21078

Did a little testing today. No load on the generator and all breakers were off besides the AC and air handler.

On Propane
Frequency dropped to 58.5hz on AC startup. 61hz while AC running
28amps on startup measured from one leg before the contactor
Voltage dropped to *180 *measured at the contactor when the AC started
Voltage stable at 241 measured at the contactor while AC is running

On Gas
Frequency the same as propane
Startup amps the same
Voltage dropped to *161 *measured at the contactor when AC started
Voltage stable at 241 measured at the contactor when AC is running

Normal grid power
*NO *voltage drop at the contactor
Could not measure frequency

This leads me to believe that the roughly 80 feet from the main panel to the AC is the problem. But I am no expert.

In the mean time, I plan to get a 50 amp plug and wire the AC directly to the generator. If that solves the problem then I don't have many options left. All I can think of is installing a second inlet box right next to the breaker box by the AC itself and backfeed the main panel from the AC line (which I don't want to do). Or, install the inlet box by the AC and physically move the generator if I need to run the AC to cool the house for a while. Thoughts?


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## iowagold

anthony21078 said:


> Manufacturer specs on the Duromax are 10-12% THD
> 
> My knowledge is limited in regards to reading schematics. If you care to thumb through those pages I can likely find them. Weather is nice today so I will hook the gen back up and get some numbers
> 
> My AC is model # ASX160601FC
> 
> 
> 
> 
> 
> Energy Efficient ASX16 Air Conditioner From Amana
> 
> 
> Searching for an air conditioner that provides cooling w/out wasting energy? Contact Amana to learn more about the energy-efficient ASX16 Air Conditioner.
> 
> 
> 
> www.amana-hac.com
> 
> 
> 
> 
> 
> View attachment 7728


good job on posting the print for the unit.
well it is all 240 volt on the outside unit.
WOW on the in rush!
yea you need a large soft start for sure..
30 amps run is what I see just for the outdoor unit.. or 7200 watts run. plus the indoor furnace unit..
if it is 10 amps for the indoor unit that works out to 2400 watts run and 9600 as the run....

from what the theory math is...
you need meters on your breaker box asap to see what the real world current is..
I see this as the gen is too small to run the amana unit..

for your gen you need closer to 18kw cont load setup or 22kw peak.. as you need 80% as the generator cont. running wattage for 14400 as the real world load wattage so 4,800 watts to run the rest of the house..

look in to the cost of an inverter outdoor compressor unit.. and see if you can find one that will have run wattage
closer to 4800 watts or less for the same btu.

in that video is there a mini split ac unit out there??
another idea you could use low current mini split units for when you are on gen power.


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## iowagold

anthony21078 said:


> Did a little testing today. No load on the generator and all breakers were off besides the AC and air handler.
> 
> On Propane
> Frequency dropped to 58.5hz on AC startup. 61hz while AC running
> 28amps on startup measured from one leg before the contactor
> Voltage dropped to *180 *measured at the contactor when the AC started
> Voltage stable at 241 measured at the contactor while AC is running
> 
> On Gas
> Frequency the same as propane
> Startup amps the same
> Voltage dropped to *161 *measured at the contactor when AC started
> Voltage stable at 241 measured at the contactor when AC is running
> 
> Normal grid power
> *NO *voltage drop at the contactor
> Could not measure frequency
> 
> This leads me to believe that the roughly 80 feet from the main panel to the AC is the problem. But I am no expert.
> 
> In the mean time, I plan to get a 50 amp plug and wire the AC directly to the generator. If that solves the problem then I don't have many options left. All I can think of is installing a second inlet box right next to the breaker box by the AC itself and backfeed the main panel from the AC line (which I don't want to do). Or, install the inlet box by the AC and physically move the generator if I need to run the AC to cool the house for a while. Thoughts?


cool on the numbers..
what is the wire size and breaker size on the feed from the breaker panel to the ac comp unit?


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## iowagold

I see your thought, sag from small long feed wire.
there is also drop on relay contacts, and breaker contacts if the current is close

or parts are bad on the breaker contacts and or relay contacts.

with that much on the in rush.. or lock current.. it will fatigue parts over time.
and check your screw terminals and wire nuts!! could have a burned one some where..


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## anthony21078

iowagold said:


> good job on posting the print for the unit.
> well it is all 240 volt on the outside unit.
> WOW on the in rush!
> yea you need a large soft start for sure..
> 30 amps run is what I see just for the outdoor unit.. or 7200 watts run. plus the indoor furnace unit..
> if it is 10 amps for the indoor unit that works out to 2400 watts run and 9600 as the run....
> 
> from what the theory math is...
> you need meters on your breaker box asap to see what the real world current is..
> I see this as the gen is too small to run the amana unit..
> 
> for your gen you need closer to 18kw cont load setup or 22kw peak.. as you need 80% as the generator cont. running wattage for 14400 as the real world load wattage so 4,800 watts to run the rest of the house..
> 
> look in to the cost of an inverter outdoor compressor unit.. and see if you can find one that will have run wattage
> closer to 4800 watts or less for the same btu.
> 
> in that video is there a mini split ac unit out there??
> another idea you could use low current mini split units for when you are on gen power.


I have a split AC for my finished basement. Central AC is for the rest of the house. I believe the split is 2 or 2.5 ton so if I really needed cool air in the summer, the family and I could be in the basement. 



iowagold said:


> cool on the numbers..
> what is the wire size and breaker size on the feed from the breaker panel to the ac comp unit?


Main panel to outdoor AC breaker is 6 guage. AC breaker to AC unit is 8 gauge.



iowagold said:


> I see your thought, sag from small long feed wire.
> there is also drop on relay contacts, and breaker contacts if the current is close
> 
> or parts are bad on the breaker contacts and or relay contacts.
> 
> with that much on the in rush.. or lock current.. it will fatigue parts over time.
> and check your screw terminals and wire nuts!! could have a burned one some where..


Im being told that if the long run of 80 feet of wire is causing the voltage drop on generator power, then a voltage drop would also occur when using grid power. If that is true, wiring a second inlet box near the AC unit would be pointless. I honestly just dont know....

Maybe the best route is to try the soft start and hope for success


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## ToolLover

I am going to offer a suggestion:
Go to you local Distributor for HVAC.
Ask for: Brand name: SUPCO # SPP6 Super Boost Relay and hard start capacitor or buy it online.
Dealer cost is $17.00.
I would also get a new start cap as you have possibly damaged the one in the AC unit.
The AC unit will run on a damaged cap, but the compressor pays for it.
Buy American made only.
Check to see if it is swelled.
You should parallel the caps and the necessary connectors come with the unit.
You will have to get a mounting bracket also.
If your fan starts and runs backwards, you have to switch the fan leads.
I am adding a note of my loss of undertanding: What is the tons on your unit?
My AC scroll unit is 4 tons and draws 11 amps.
Maybe your Amana does not have a scroll compressor, if not your start amperage is high.
I want to add a note: I can tell when my caps have failed as the house lights blink when the AC starts.
I have had to replace the caps twice.
I often wonder if my Generac is taking the caps out due to slightly dirty voltage. (THD)
You may have already damaged your caps by the way it runs in the video.
Check as see if your lights blink when it starts on utility.


----------



## iowagold

hey tl what was your amps draw when the caps were bad?
house lights dim I bet it was BIG numbers on inrush!

yea
darn lightning here is hard on ac compressors and caps, relays etc..
we get some hard hits on the powerlines.
I use the whole house surge protection to slow down the damage from small hits...
links are below;





HONDA_GENERATOR


HONDA_GENERATOR



www.poustusa.com





lol a direct hit... well there is not much stopping a BIG direct lightning hit...
unless every thing is unplugged!!
I started running the house on manual generator when the storms are near!!
GRIN!! getting a head of the outage and the damage!!
last fall the house next door got a direct hit.. I was on gen. no damage.
it fried the pole pig.. at least they were on the next over pig from mine.
they had no power for 24 hours while utilities crews were fixing stuff in town like mad men..
I stayed on gen just in case as they were doing main line replacement..


----------



## Melson

ToolLover, I'll take a _guess_ on the short capacitor life as being caused by switching and/ or generator AVR voltage spikes.


----------



## iowagold

hey melson would a mov help on the cap life?
just a thought..


----------



## ToolLover

@ Iowagold: mov??? explain please
As to lights blinking: I told my AC guy they were blinking, but he paid no attention.
I figured it out on my own and put the soft start cap in place.
No lighting in my area just 60 year old oak trees falling all the time.
@ Melson: Yep, the AVR went out and 120 vac went to 160 vac.
You know Melson, I had PTO generators and they lacked AVR's. Never had a moments problem.
I am not a fan of AVR's and I no longer trust Generac although I have one.
A while back I made repairs on a friend's Briggs Stratton and it did not have an AVR.
Frequency was set by gas regulation.
I guess I should buy that Onan 45 KW unit and sell the Generac.


----------



## iowagold

MOV
from the net








Varistor - Wikipedia







en.wikipedia.org




they use these on spike suppression... and surge suppression...
values depend on voltage and current..
all that pointy head engineer stuff lol!!
at least that is what my sister calls it!!


----------



## iowagold

this link below has a few circuits and design applications ac and dc .








Metal Oxide Varistor (MOV), Basics, Working, Specifications, Performance, Features


The basics of metal oxide varistor (MOV) along with its working and specifications are given and also its performance and other features.




www.circuitstoday.com


----------



## ToolLover

I installed those on the utility side of the line voltage in the early 80's for lightning spikes.
I am not a fan of tinkering with the utility side of a main.
Sorry but no thanks Iowagold!
Now at to Anthony's problem:
I am thinking he has had enough of our BS and just needs to get a bigger generator.


----------



## drmerdp

A couple things, the SUPCO # SPP6 Super Boost is a hard start capacitor with potential relay. The OP has a hard start capacitor already installed, just a different company, the 5-2-1 compressor saver. I also have a 5-2-1 installed on my circa 2001 3.5 ton rheem with scroll compressor. I also used to have dimming lights before adding the hard start compacitor.

His 135 amp LRA is not unusual, especially for a 5ton unit. My unit has a LRA of 110 but I measure 130amp max amps without the hard start and 110amps with the hard start. (My klein clamp meter does not have an Inrush setting but I can measure max amps, not entirely sure if thats the same thing.)My RLA is 21amps but I measure 16 amps running. 

I looked up the Duramax XP12000EH and the specs state a 457cc engine at 18hp lol. I hate how these chinese generators are rated. My old champion 7000 running / 9000 surge had a 439cc engine and I load tested it to 7500 on gasoline before the engine speed dipped to unfavorable speeds. I disconnected the load when the HZ dropped to 56.

The fact that Duromax claims 9000 running from a 457cc engine is in my opinion an embellishment. The 10-12% THD isn't to bad. 

I do think a soft start will still help the cause and is definitely worth installing and testing.


----------



## ToolLover

@ drmerdp: 16 amps running on a 3 1/2 ton unit!
My 4 ton only pulls 11 amps running or at least it did that last time I checked it.
Now you are making me think I need to check it agian.
But before I spent $300 on soft start, I would get me a proper generator as the OP has not had a problem before he tried to get the generator to do more than it can do.
The OP is trying to get a pony to pull a wagon that a team of mules needs to pull.


----------



## KRE

One thing no one seems to grasp is that LRA is based upon a A/C unit that has not been ran for over 30 minutes. When you remove power from a compressor then reapply it the head pressure does not drop like snapping your fingers. A compressor starting with head pressure applied is hard to start an done enough times it will damage the motor in the compressor. That applies to your freq an deep freezer alike. Most newer system have a timer that picks up when power drops but only if it drops to were the circulating voltage drops below the where the timers drop out voltage is set. Many cheap transfer switches do not have in-phase monitors or a time delay neutral (stop in the middle) to prevent this. Therefore most that know what they are doing most always never use these cheap systems in the first place. Even though I added the programed transition function to my Onan ATS I still installed a timer on my HVAC Unit that will drop it's control power if it's sees anything longer than a 100Ms power outage. After it times out 10 minutes later, the timer returns control power, same with the freg an freezers. 
Not everything in EPG is as simple as many think it is. A little knowledge is great but it can also be dangerous or costly, by not knowing all ramifications of the task you wish to complete. Those of you with Air Compressors, unhook your unloader valve an try to re-start the compressor on utility power after the tank is full, an see how that works out. Small rope/battery start generators are not an infinite buss, like utility.
The comments about fuel were interesting.


----------



## anthony21078

Perhaphs the numbers I posted for amps is deciving. Prior to installing the 5-2-1 hard start, the AC was pulling 49 amps on startup per leg measured at the main panel breaker. Measured at the common wire at the AC it was 98 amps. After installing the 5-2-1 hard start, the AC was pulling 30-34 amps on startup per leg at the main panel breaker. Ac common wire would be 60-68 amps. A rather significant drop for a hard start device that was 30$. LRA is 135 for this 5 ton Amana ASX16 single speed scroll compressor that was installed June 2018. I have seen as high as 160 LRA for other 5 ton units. Knowing this draw was a matter of milliseconds, my hope was a 12000watt surge generator _*could possibly*_ handle the task of starting this AC with all other house breakers OFF. 

The AC starts but it is struggling so thats why Im here to find a possible solution instead of buying a larger generator. If the process to buy, try/test and then possibly return a 250lb generator was easy, I would have done that already and tried a larger model. The next model size I would consider would be a 15000watt surge, 12000w running model for almost 1800$. I picked up the current model I have now for 850$ on sale. A 300$ soft start device might be worth a shot when cost is considered. If the soft start doesnt work, I'll look at the 300$ investment for the device as support tool to prolong the life of my AC (maybe, maybe not).

@ToolLover the run cap is fine. On grid power the AC starts and runs as normal. That was the last check yesterday after testing was done with the generator. 

My AC has a coresense diagnostic module. There are no error codes present on the diagnostic unit. One of the possible faults the module will detect and throw a blinking error code is when low voltage is supplied to the AC. Although the voltage supplied by the generator (180v at startup) is lower then 240 supplied by grid power, maybe its right at the limit of being able to start the unit but not low enough to throw a error code (this is just an assumption).

I have lived in this home for almost 2 years and only lost power once so far for a few hours. Many of my neighbors state that power loss is extremely rare for long periods of time with the exception of a hurricane we experienced in 2012. I truely believe I wont need to use this generator but the idea of having a backup for the whole home makes me sleep better.


----------



## ToolLover

@ KRE: Is it possible that a Scroll compressor only needs a short time to drop head pressure?
My unit only has a 3 minute delay for restart.....I think.
@anthony21078 : The facts are not in your favor. Get a more powerful generator.
In the long run you will be better off.


----------



## drmerdp

@KRE Good point with the head pressure of a recently ran compressor. Almost all central AC units built in the last 30 years have a TXV, thermal expansion valve. These valves dont let the system equalize quickly, resulting in a significant amount of head pressure. Trying to make your compressor go from locked to moving instantly against this pressure requires a greater amount of force to overcome it. 

The micro air soft starter has a short start timer. It’s 5 minutes by default I’m not sure if it can be extended longer. Also the ramping effect of soft starters reduces the difficulty of overcoming that head pressure. Scroll compressors while more efficient in operation have higher starting demands then the old piston reed valve compressors. R410 systems operate at even high pressures then the old R12 systems.

@ToolLover You have me second guessing my memory. If spring ever hits the northeast Ill confirm my measurements. I don’t want to run my AC until we hit around 65-70.


----------



## KRE

Scroll compressors can an will run backwards(go into heating) depending where the sine-waves interlock at ATS closure. Seen that many times over the years. The only way to stop that, even with an ATS that has a properly adjusted an working in-phase monitor is a timer to block the compressor for 5 minutes when the gen starts, or when utility returns. This timer can also be operated via the relays that provide power to the coil clearing contacts. I've modded many over the years, an instructed 1K of techs in the how an why. Any ATS w/o a in-phase monitor or time delay neutral should never be used when the load has motors of any kind involved, period. The junk ATS's that come with box store gensets have the ability to fed 480Vac into a home that is set up for 240Vac single phase should it not have an IPM or TDN, and depending the gen sets slip ratio, this can smoke test many things in the home over time.


----------



## KRE

ToolLover said:


> @ KRE: Is it possible that a Scroll compressor only needs a short time to drop head pressure?
> My unit only has a 3 minute delay for restart.....I think.
> @anthony21078 : The facts are not in your favor. Get a more powerful generator.
> In the long run you will be better off.


Timers operating properly depend on many things, an when an ATS is involved all bets are off. This is why one needs to fully understand how the load effects the genset as well as how the genset performance can effect the load.


----------



## KRE

anthony21078 said:


> Perhaphs the numbers I posted for amps is deciving. Prior to installing the 5-2-1 hard start, the AC was pulling 49 amps on startup per leg measured at the main panel breaker. Measured at the common wire at the AC it was 98 amps. After installing the 5-2-1 hard start, the AC was pulling 30-34 amps on startup per leg at the main panel breaker. Ac common wire would be 60-68 amps. A rather significant drop for a hard start device that was 30$. LRA is 135 for this 5 ton Amana ASX16 single speed scroll compressor that was installed June 2018. I have seen as high as 160 LRA for other 5 ton units. Knowing this draw was a matter of milliseconds, my hope was a 12000watt surge generator _*could possibly*_ handle the task of starting this AC with all other house breakers OFF.
> 
> The AC starts but it is struggling so thats why Im here to find a possible solution instead of buying a larger generator. If the process to buy, try/test and then possibly return a 250lb generator was easy, I would have done that already and tried a larger model. The next model size I would consider would be a 15000watt surge, 12000w running model for almost 1800$. I picked up the current model I have now for 850$ on sale. A 300$ soft start device might be worth a shot when cost is considered. If the soft start doesnt work, I'll look at the 300$ investment for the device as support tool to prolong the life of my AC (maybe, maybe not).
> 
> @ToolLover the run cap is fine. On grid power the AC starts and runs as normal. That was the last check yesterday after testing was done with the generator.
> 
> My AC has a coresense diagnostic module. There are no error codes present on the diagnostic unit. One of the possible faults the module will detect and throw a blinking error code is when low voltage is supplied to the AC. Although the voltage supplied by the generator (180v at startup) is lower then 240 supplied by grid power, maybe its right at the limit of being able to start the unit but not low enough to throw a error code (this is just an assumption).
> 
> I have lived in this home for almost 2 years and only lost power once so far for a few hours. Many of my neighbors state that power loss is extremely rare for long periods of time with the exception of a hurricane we experienced in 2012. I truely believe I wont need to use this generator but the idea of having a backup for the whole home makes me sleep better.


Never buy a generator using surge numbers, as depends upon the alternators excitation system. In a closed system like all box store units they have the most simple engine governors with a very basic excitation system. I have yet to see any box store generator preform it rated output (voltage/amps) for 4 hrs under full load. Some will not pull full load from the box ever, as they are way over rated, be it the prime mover or the alternator. I except a class action law suite one day based upon this.


----------



## ToolLover

@KRE: So, you got me to thinking about the delay. I turned the power off to my outside heat pump.
I let it set for a minute or two.
Then repowered it. Then I turned the thermostat up and waited.
Like you said it took FIVE minutes to restart.
I was standing nearby and it and I most certain it did grunt a little when it started.
I guess I should have put a clip on amp meter on the wire to check the starting amperage.
Sorry I let that slip.😧


----------



## drmerdp

KRE said:


> Never buy a generator using surge numbers, as depends upon the alternators excitation system. In a closed system like all box store units they have the most simple engine governors with a very basic excitation system. I have yet to see any box store generator preform it rated output (voltage/amps) for 4 hrs under full load. Some will not pull full load from the box ever, as they are way over rated, be it the prime mover or the alternator. I except a class action law suite one day based upon this.


Agreed, a class action lawsuit would be great for consumers being deceived buy embellished ratings. Quality companies do not inflate their specs.

Hondas iAVR generators use an electric governor. Essentially a stepper motor actuated throttle plate that in my experiance is fantastic at keeping 60Hz and the voltage at above the rated load stayed perfect. This was my neighbors EB6500 that I recently tuned up. My only complaint was the electric governor is a bit slower to react to a BIG load all at once but did stabilize back to a perfect 59.X Hz without the droop mechanical governors have.

I think one of the best bang for the buck generators is the Northstar line from northern tool. Low THD, quality components, and parts availability. 4 year consumer warranty, but I do not know what the service network looks like.

They don't come dual fuel, but I find that aftermarket Tri-fuel kits to be far better then the OE equipped dual fuel setups. UScarb has a kit for pretty much any application.






NorthStar Portable Generator 13,000 Surge Watts, 10,500 Rated Watts, Electric Start, CARB Compliant | Northern Tool


Rugged, newly designed NorthStar® 13,000 Watt Generator features a smaller footprint and the latest Honda V-Twin engine to <b&g...




www.northerntool.com





I have a customer with this generator and it runs her 4ton through a 50amp inlet without issue.


----------



## iowagold

they cool thing on the NorthStar units they put them together here in the states.
at least on the units I have seen.
the other good gen mfg is Gillette..
we have those for the roofing crews where they use seam sealers for the firestone roof system..
but they are thirsty !!
v twin honda… and they run at full rpm no eco mode. but have a gov system...

yea the big thing is to plan a system..
you need to be able to be at 50% of the system run current or less.
that way you have the head room for the true start current..
most all of the gens will not stand running at 75% or higher current for sustained time..
parts just over heat... or let go..

yea most of the Jina gens just do not even have as close to the numbers as they post..
the cool think is the Honda Eu gens will stand the rated power..
the are just over built well and that is why they cost more!!
you get what you pay for..


I always say do a site survey first with a chart recorder...
then do a spread sheet of every thing to be connected...
a breaker box meter system is always smart money spent.
and will help you on the load selection later when on generator power.


----------



## TickTockGlock

I know I'm a little late to the party but my question is along the lines of this thread. I have a 4 ton unit with 108 LRA. However, my in rush amps were 80 when I tested them. I have a Cat 12000E generator with 15,000 surge, 12,0000 running. I was between putting a hard start kit or a soft start kit on my unit. The hard start is way less expensive but still feel like the soft start is going to be more efficient not only when I want to run my ac on generator power but also while on utility. I just haven't seen a ton of people running their home on generator power with the ac having a soft start kit all I ever see is the hard start kits or RVs with a soft start, so I am a little leery of it all. Any advice would be appreciated!


----------



## iowagold

go the soft start
see this link below
click here for the softstart link
they are the only way to go...
yea hard start units help... but a soft start ramps up the power gradual so you can use a smaller gen set..
wow on the close to 110 amps locked rotor!
i would look at an inverter ac unit...
they are pricy, but way less power to run them.
you are only 48 amps run on that gen set...
and 60 amps peak....
i would be thinking inverter ac units...
or switching to mini split units... with inverters...

way less power to run them even on grid power per btu.
i would go 2 times larger unit than the charts say on the mini split units..
that way they do not have to work as hard to keep up on super hot days...

and insulate the heck out of the house!!
lol i have r52 in the attic now and working on the walls this summer...
so far the heat has put a stop in the construction update plans...


----------



## TickTockGlock

iowagold said:


> go the soft start
> see this link below
> click here for the softstart link
> they are the only way to go...
> yea hard start units help... but a soft start ramps up the power gradual so you can use a smaller gen set..
> wow on the close to 110 amps locked rotor!
> i would look at an inverter ac unit...
> they are pricy, but way less power to run them.
> you are only 48 amps run on that gen set...
> and 60 amps peak....
> i would be thinking inverter ac units...
> or switching to mini split units... with inverters...
> 
> way less power to run them even on grid power per btu.
> i would go 2 times larger unit than the charts say on the mini split units..
> that way they do not have to work as hard to keep up on super hot days...
> 
> and insulate the heck out of the house!!
> lol i have r52 in the attic now and working on the walls this summer...
> so far the heat has put a stop in the construction update plans...


Yeah house is only about 5 years old so new AC isn't really in the cards, so trying to find a way to make what i have already work for when the next hurricane takes the power out for a week haha. I have foam insulation on the roof line and extra thick batts in the walls, the house is very energy efficient. I was looking at the micro air soft start as pretty much every review I have seen on them praises them and they claim to lower amp draw by 50-70 percent so thought I would be good.


----------



## anthony21078

If you compare your situation to mine then you have larger generator then me but have a smaller ac. Hard start would probably do the job but the soft start is overall a better device.

I put this project on hold but still have plans of buying the soft start and keeping the generator I have. Still haven't lost power yet


----------



## TickTockGlock

anthony21078 said:


> If you compare your situation to mine then you have larger generator then me but have a smaller ac. Hard start would probably do the job but the soft start is overall a better device.
> 
> I put this project on hold but still have plans of buying the soft start and keeping the generator I have. Still haven't lost power yet


You raise some good points lol. Yeah I really went back and forth on the hard start/soft start just because of price. But I do think the soft start makes the most sense all the way around. We didn't get hit with a hurricane last year in Florida so we are due this year lol So wanting to be ready.


----------



## iowagold

soft start is a big price pill to swallow.

but they are 2 different ways to get a compressor to role over.

the soft start roles it over with gradual voltage and current in steps.

a hard start boosts the start current for a "jolt" of extra current.

so think long lever pry bar as a soft start.. gradual power
and a sledge hammer as a hard start!! hard pounding right now current..
both would get a ball rolling...
but the pry bar is way easier on the ball! less stress on everything.

Grin!!
and a soft start has been proven to make a compressor winding, wiring and relays as contactors last longer in industrial applications.

go with the soft start.


----------



## TickTockGlock

Just wanted to update you guys. I installed the microair soft start kit on my 4 ton AC. In rush amps were dropped to 32 and the generator barely even flinches when the AC unit comes on. Did a test with most of my house being powered and the AC kicking on and it did pull the generator down but only for a split second. The soft start kit was the way to go!


----------



## anthony21078

You sold me.....

I lost power for about 9 hours with this hurricane. I didnt bother using the 5 ton ac because it was only 70 degrees. I got lucky. If it was hotter outside I would have been pissed!

I'm buying the micro air now.

@TickTockGlock where did you purchase from?


----------



## TickTockGlock

From Isaias? When it went by us it was just a tropical storm offshore so not too bad. Yeah good thing it was only 70, hard to sleep when it's hot! I ordered it through microair's website. I will leave a link for the model you will probably need for your 5 ton, but use their tool that will show you exactly what you will need. EasyStart™ 368 Soft Starter


----------



## anthony21078

TickTockGlock said:


> From Isaias? When it went by us it was just a tropical storm offshore so not too bad. Yeah good thing it was only 70, hard to sleep when it's hot! I ordered it through microair's website. I will leave a link for the model you will probably need for your 5 ton, but use their tool that will show you exactly what you will need. EasyStart™ 368 Soft Starter


Yes from Isaias. My neighborhood got lucky and only lost power for a short time. Many surrounding areas are still without power and not expected to regain power until Saturday. 

I sent a message to MicroAir support asking them about my unit. I have a Coresense disagnostic module wired into my unit and Im not sure if that will interfere with the EasyStart.


----------



## iowagold

link for the page with the soft start unit below
Micro Air soft start link is on this page
yea after using them for the last couple of years.
they are the trick setup for sure.

the state fair folks swear by them.
they can run one eu2200i on a camper and fire one ac unit!

they help on the home stuff to stop the light dimming when the big units kick in as well.
i had the window ac units that had a bit over 100 amps in rush..
now they are below 18 amps. and that is a split second in rush.

120 vac as well as 240 vac they are the trick setup!


----------



## TickTockGlock

anthony21078 said:


> Yes from Isaias. My neighborhood got lucky and only lost power for a short time. Many surrounding areas are still without power and not expected to regain power until Saturday.
> 
> I sent a message to MicroAir support asking them about my unit. I have a Coresense disagnostic module wired into my unit and Im not sure if that will interfere with the EasyStart.


Yup what your neighbors are going through is exactly why I wanted to set all of this up. I am out in the country and every time a hurricane comes through here it is 5-7 days before they get our power back up out here. 

Micro air was awesome about responding to my messages. During business hours I usually got a response from a guy banned Roger within 5-10 minutes. I believe your can still install it but there is an extra step of adding some jumpers on your diagnostic module. But they will definitely let you know.


----------



## TickTockGlock

iowagold said:


> link for the page with the soft start unit below
> Micro Air soft start link is on this page
> yea after using them for the last couple of years.
> they are the trick setup for sure.
> 
> the state fair folks swear by them.
> they can run one eu2200i on a camper and fire one ac unit!
> 
> they help on the home stuff to stop the light dimming when the big units kick in as well.
> i had the window ac units that had a bit over 100 amps in rush..
> now they are below 18 amps. and that is a split second in rush.
> 
> 120 vac as well as 240 vac they are the trick setup!


My experience has been great as well. Lowered the in rush amps by about 60% and the unit runs a little quieter. The biggest key though is it allowed me to run my 4 ton unit with my portable generator without any strain.


----------



## iowagold

yup a cool bit of kit for sure!
link for the page with the soft start unit below
Micro Air soft start link is on this page


----------



## anthony21078

I have exchanged several emails with Roger from MicroAir about my generator/AC issues. I provided him with all the information about equipment and the testing Ive done. I will post his comments in regards to using the EasyStart to solve my problem.

Me
"I am interested in trying the ASY-368-X72 on my Amana 5 ton AC model# ASX160601 with a LRA of 125 to see if a Duromax xp12000eh generator can start it properly. Currently I have a 3-2-1 hard start installed on the AC. The AC unit will start under generator power but it seems to "struggle" or hesitate to start compared to using regular grid power. But once the AC is up and running there is strange vibration that causes the grate to rattle. There is much more to this and very hard to explain in a message. However, I know a 12k surge/9k running generator might be a stretch to properly power a 5 ton AC but I would like to try your product. After reading the installation instructions it seems like a simple install. My AC unit has a Coresense diagnostic module wired into the contactor, wired into the compressor and I believe wired into the hi/lo switches. Will this module interfere with the EasyStart? Is there anyway I can upload pictures of my unit?"

Roger
"Your air conditioner wants 125 amps to start properly and your generator can supply only about 50 of that with 12,000 watts peak. Fortunately it supplies that power long enough that the motor can start before the generator can overload which is not the case for many similar installations. Most manufacturers recommend a 20K generator to start a 5 ton so you are definitely on the fringe for the start.

Running however, it has plenty of power so why does it vibrate? The problem there is the generator does not supply a very steady 60Hz power waveform. We have seen that with quite a few generators and there in not much you can do about it. EasyStart can however help reduce the start current to well under the 50 amp peak of your generator allowing it to start the same as if it was on AC mains power.

EasyStart normally has a start delay that can interfere with these monitoring circuits. We have instructions in our home installation manual that will tell you how to eliminate the delay so it will not interfere with your monitoring system"

Me
"Great info thank you. The distance from the main breaker panel to the AC panel is approximately 60 feet of 6 gauge wire. I'm curious if this distance is also a contributing factor to the voltage drop. I was planning on wiring the generator directly to the AC panel to see if the voltage drop on startup was not as severe. Just trying to remove all variables in hopes of not having to buy a larger generator.

To clarify, 34 amps was measured at the main breaker panel using one leg on grid power WITH the hardstart installed. However, that number did not change under generator power. Without the hardstart, I measured 49 amps in rush on grid power. 

The specs for this generator state 10-12% THD which may be too much for this AC.

So I suppose after all this it's safe to say the EasyStart will start my AC but I will _likely _have the same issues I have now. In your opinion, should I even bother trying the EasyStart?"

Roger
"#6 AWG wire at 125 amps LRA = a 6 volt loss which is negligible at 240 VAC. It is possible a little higher due to the resistive losses at the connections but still unimportant.

Measuring 34 and 49 amps suggests the measurement equipment is not capturing the value correctly. Adding the hard start cap does not change the current. It shifts the power factor a little and provides additional current to the start winding that is out of phase with the main run current. The timing of the start will reduce by a small amount which will contribute to the measuring inaccuracy.

It does not matter if you measure one leg or the other. The current in a single phase system flows from one leg to the other so it has a singular path and phase.

10-12% THD is probably acceptable and won’t cause heating or damage but certainly can result in the noise you are hearing.

You will certainly have the same issue with noise you now have since it is harmonically related. You may find that there are situations where the generator will not start the compressor in the future. Yesterday I spoke to a customer with a 19K generator that will not start his 4K compressor even after the generator company came over and checked the operation. The company simply said his will not start and left it at that! I am surprised by your results so if you find you are no longer having the success you expect, EasyStart can help get it started again."

Me
"Your information is invaluable. Much appreciated.

If the AC starts and runs under generator power and the only visible/audible issue is this strange harmonic distortion we hear in the video, based on your experience is it possible to state whether or not this is causing excessive wear on components and or any internal damage on the AC? Or just a harmless side effect of dirty generator power?

Based on your statement it appears I have 2 options so please correct me if I am wrong.

1)Find a generator with less THD in the 12k surge range and use the EasyStart
2)Find a larger generator (perhaps 15k surge) also with less THD and use the EasyStart IF needed

I suppose staying in the 12k surge range _may _be acceptable to start this unit since it works with my current generator."

Roger
"It is hard to say if there are any long term effects on running the AC with this noise since the characteristic distortion can be different with each power source and load. If you are using this for emergency use during storms and such, there is probably little risk in using it for a few days a year. If this is an off grid application where this is the primary power then you may want to contact the manufacturer of the AC to see what their recommendations or limits are for THD."


.
.
.

In conclusion, dirty generator power is likely the cause of strange AC noise. I suppose I have to bite the bullet and get a generator with less THD? If thats the case, maybe I should get a larger generator as well but the cost from a 12k surge to 15k surge basically doubles in price. This 12k surge unit I have now will start my AC. Perhaphs I can find another 12k generator with lower THD AND use the EasyStart.

Quick search came up with this unit. Doesnt appear to be very popular but they "claim" 5% THD and is 15k surge








A-iPower SUA15000EC 12000W/15000W Electric Start Gas Generator New


Authorized Dealer. Free shipping on generators. A-iPower SUA15000EC 12000W/15000W Electric Start Gas Generator New. 2 year warranty.




factorypure.com


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## TickTockGlock

anthony21078 said:


> I have exchanged several emails with Roger from MicroAir about my generator/AC issues. I provided him with all the information about equipment and the testing Ive done. I will post his comments in regards to using the EasyStart to solve my problem.
> 
> Me
> "I am interested in trying the ASY-368-X72 on my Amana 5 ton AC model# ASX160601 with a LRA of 125 to see if a Duromax xp12000eh generator can start it properly. Currently I have a 3-2-1 hard start installed on the AC. The AC unit will start under generator power but it seems to "struggle" or hesitate to start compared to using regular grid power. But once the AC is up and running there is strange vibration that causes the grate to rattle. There is much more to this and very hard to explain in a message. However, I know a 12k surge/9k running generator might be a stretch to properly power a 5 ton AC but I would like to try your product. After reading the installation instructions it seems like a simple install. My AC unit has a Coresense diagnostic module wired into the contactor, wired into the compressor and I believe wired into the hi/lo switches. Will this module interfere with the EasyStart? Is there anyway I can upload pictures of my unit?"
> 
> Roger
> "Your air conditioner wants 125 amps to start properly and your generator can supply only about 50 of that with 12,000 watts peak. Fortunately it supplies that power long enough that the motor can start before the generator can overload which is not the case for many similar installations. Most manufacturers recommend a 20K generator to start a 5 ton so you are definitely on the fringe for the start.
> 
> Running however, it has plenty of power so why does it vibrate? The problem there is the generator does not supply a very steady 60Hz power waveform. We have seen that with quite a few generators and there in not much you can do about it. EasyStart can however help reduce the start current to well under the 50 amp peak of your generator allowing it to start the same as if it was on AC mains power.
> 
> EasyStart normally has a start delay that can interfere with these monitoring circuits. We have instructions in our home installation manual that will tell you how to eliminate the delay so it will not interfere with your monitoring system"
> 
> Me
> "Great info thank you. The distance from the main breaker panel to the AC panel is approximately 60 feet of 6 gauge wire. I'm curious if this distance is also a contributing factor to the voltage drop. I was planning on wiring the generator directly to the AC panel to see if the voltage drop on startup was not as severe. Just trying to remove all variables in hopes of not having to buy a larger generator.
> 
> To clarify, 34 amps was measured at the main breaker panel using one leg on grid power WITH the hardstart installed. However, that number did not change under generator power. Without the hardstart, I measured 49 amps in rush on grid power.
> 
> The specs for this generator state 10-12% THD which may be too much for this AC.
> 
> So I suppose after all this it's safe to say the EasyStart will start my AC but I will _likely _have the same issues I have now. In your opinion, should I even bother trying the EasyStart?"
> 
> Roger
> "#6 AWG wire at 125 amps LRA = a 6 volt loss which is negligible at 240 VAC. It is possible a little higher due to the resistive losses at the connections but still unimportant.
> 
> Measuring 34 and 49 amps suggests the measurement equipment is not capturing the value correctly. Adding the hard start cap does not change the current. It shifts the power factor a little and provides additional current to the start winding that is out of phase with the main run current. The timing of the start will reduce by a small amount which will contribute to the measuring inaccuracy.
> 
> It does not matter if you measure one leg or the other. The current in a single phase system flows from one leg to the other so it has a singular path and phase.
> 
> 10-12% THD is probably acceptable and won’t cause heating or damage but certainly can result in the noise you are hearing.
> 
> You will certainly have the same issue with noise you now have since it is harmonically related. You may find that there are situations where the generator will not start the compressor in the future. Yesterday I spoke to a customer with a 19K generator that will not start his 4K compressor even after the generator company came over and checked the operation. The company simply said his will not start and left it at that! I am surprised by your results so if you find you are no longer having the success you expect, EasyStart can help get it started again."
> 
> Me
> "Your information is invaluable. Much appreciated.
> 
> If the AC starts and runs under generator power and the only visible/audible issue is this strange harmonic distortion we hear in the video, based on your experience is it possible to state whether or not this is causing excessive wear on components and or any internal damage on the AC? Or just a harmless side effect of dirty generator power?
> 
> Based on your statement it appears I have 2 options so please correct me if I am wrong.
> 
> 1)Find a generator with less THD in the 12k surge range and use the EasyStart
> 2)Find a larger generator (perhaps 15k surge) also with less THD and use the EasyStart IF needed
> 
> I suppose staying in the 12k surge range _may _be acceptable to start this unit since it works with my current generator."
> 
> Roger
> "It is hard to say if there are any long term effects on running the AC with this noise since the characteristic distortion can be different with each power source and load. If you are using this for emergency use during storms and such, there is probably little risk in using it for a few days a year. If this is an off grid application where this is the primary power then you may want to contact the manufacturer of the AC to see what their recommendations or limits are for THD."
> 
> 
> .
> .
> .
> 
> In conclusion, dirty generator power is likely the cause of strange AC noise. I suppose I have to bite the bullet and get a generator with less THD? If thats the case, maybe I should get a larger generator as well but the cost from a 12k surge to 15k surge basically doubles in price. This 12k surge unit I have now will start my AC. Perhaphs I can find another 12k generator with lower THD AND use the EasyStart.
> 
> Quick search came up with this unit. Doesnt appear to be very popular but they "claim" 5% THD and is 15k surge
> 
> 
> 
> 
> 
> 
> 
> 
> A-iPower SUA15000EC 12000W/15000W Electric Start Gas Generator New
> 
> 
> Authorized Dealer. Free shipping on generators. A-iPower SUA15000EC 12000W/15000W Electric Start Gas Generator New. 2 year warranty.
> 
> 
> 
> 
> factorypure.com


Yeah it could very well be the THD%. I bought one that has 5% THD for the very purpose of protecting the sensitive electronics in the house. Which your AC unit definitely does have some sensitive electronics. You will probably get a similar noise in your house if on generator power and you turn on a ceiling fan for instance. I know I did before getting the bigger generator with the lower THD, now the noise is almost completely unnoticeable. I bought the Cat RP12000E. It's really solid unit and I couldnt be happier. I dont know a lot about the brand of generator that you listed if I am being honest. I have only seen them advertised. Bottom line, if your current generator has a high THD then anything you put on the AC will probably still make the noise you are hearing. That being said, it depends how much of your house you want to power along with the AC as to what application you end up going with. I installed a hard start kit on my dads house and hes happy with it but his unit is just a 2.5 ton so not a whole lot of strain on the generator anyways.


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## iowagold

cat makes nice power!

yea if you are doing any gen sets for back up and want ac units to work use the soft starter unit!
click here for the gen connection page with the easy start unit link
trust me they work!


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## anthony21078

I was bored today so I did a little more testing. I wired the AC directly into a 50 amp plug to go right into the generator to see if I could rule out the 70ish feet of the cable running to my main panel as a problem. The air handler and the rest of the home was still using grid power.

Set the AC to cool and after the compressor kicked on there was approximately a 2-3 second delay before the fan turned on. Under grid power there is approximately a 1 second delay from the compressor turning on until the fan turns. 

Even though the generator was literally right next to the AC I did not hear or feel any abnormal or excessive vibration/harmonic distortion that I previously heard a while back.

I was happy with the way the AC was running so I shut everything down and decided to test again from the other side of the house through the inlet box just to see if the vibration was still there. Surprisingly, while running the generator through the inlet box which has the AC approximately 70 feet from the main panel, the vibration and excessive noise that used to be there was no longer there. There was a small hint a vibration coming from the unit but nothing like it was a while back. 

Again, I shut everything down and put the AC back to grid power and that tiny little bit of vibration that I noticed on the generator power was not there.

After thinking about it for a while I remembered a few weeks ago that I remove the grate on top of the AC to clean out some leaves that were in there. I guess repositioning the grate caused that noise to stop.

So now I wonder.... was this really a problem from the beginning or just a grate that was tightened down but perhaps sitting in an awkward position giving the appearance that the whole unit was not responding well to generator power. But remember, there is a tiny bit a vibration felt through the unit right now that is not there using grid power.

Nevertheless, at the moment it appears that my issue was related to a grate that was giving a false impression of a problem that actually wasn't there. That's just an assumption right now but I hope that's the case. However, I will be buying the soft start to lower that initial startup average even more


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## drmerdp

My 3.5 ton unit reacted the same way with my eu7000. In my case my AC unit is old and tired. My inrush Numbers exceed the nameplates LRA. LRA is 110amps my unit tests at 130amps and soft start dropped inrush to 55amps. With or without the soft start the compressor had a notable vibration. My EU7000 is just to small to start the Compressor Effectively.

In my case frequency stays perfect but voltage drops below the 200 and the compressor never gets up to speed and vibrates like crazy.

When I parallel my eu7000 with my eu2200 the AC unit starts effortlessly.... Not my idea of a win, but at least I have an ace up my sleeve.

In your case I don’t think THD is the problem. You need a good quality meter with a fast refresh rate like a fluke meter to check your voltage at startup. Videoing my meter allowed me to catch the frame showing my voltage dropping below the minimum voltage threshold on the compressors nameplate. 208v is the number on my old Copeland scroll.


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## jimshoe

iowagold said:


> you need a soft start unit. hard start helps a bit.. but the soft start is the way to go
> EasyStart™ 368-X72 Soft Starter is the model number for the large air con unit.
> it will support up to a 6 ton unit or 72k btu.
> here is the link to the oem place to buy it direct from them
> 
> 
> 
> 
> 
> 
> 
> 
> EasyStart™ 368 Soft Starter
> 
> 
> The EasyStart™ soft start motor starter supports 115 & 230V A/C motors & employs a 4-part start ramp sequence that offers the lowest possible start-up current.
> 
> 
> 
> 
> www.microair.net
> 
> 
> 
> 
> 
> EasyStart™ 368-X72 Soft Starter
> they are pricy $338.00 usd plus shipping.
> but they are the best in class.
> they sure work right!!
> you get what you pay for..
> these help reduce the load even when on normal grid power as well.
> 
> most folks when the go to replace the old style ac units get an inverter ac unit.
> they cool so much more for less power.
> just saying if you do replace the compressor unit in the future upgrade it.


I was just reading about your topic. I've got a DuroMax EH13000/10500. I checked the specs on my AC and found the outside unit starts on 9KW and runs on 3KW. I think I will test first but with nothing else running on my 50a ckt. Here's a handy chart.


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## drmerdp

The ratings are very close to numbers I’ve seen. Useful chart.


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