# Generator Current Frequency Varies from 52HZ to 56HZ



## imran (Feb 25, 2018)

Dear Electrical Generator Experts, 
I have 20KVA Gas generator for home use, locally made with Toyota Generator. Output Voltage is 223V to 225V (almost no fluctuations) and Frequency varies from 52Hz to 55Hz on the digital frequency meter display. This frequency varies as per the load on the generator. For example if put the load for 2 ACs (2tons) then output current frequency comes down to 52HZ and at the normal load (about 2KVA), frequency rises to 55 Hz and becomes constant.

I have the following questions:
1. "Does the variation in AC frequency (From 52HZ to 56HZ) harm the other sensitive electrical appliances like CCTV cameras, routers and mobile chargers?
2. I run 3 big LED TVs on generator, would this frequency variation be harmful to the LEDs?


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## KRE (Nov 29, 2011)

(1) no
(2) no


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## Handyhiker (Sep 29, 2016)

I would raise your hertz output to 61.5 unloaded. You are running a little low. .


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## imran (Feb 25, 2018)

Handyhiker said:


> I would raise your hertz output to 61.5 unloaded. You are running a little low. .


Dear Handyhiker, 
Thanks Sir for your valuable inputs. 
At our place, electrical supply frequency is 50Hz from power supply company on the domestic connection. Considering this fact, most of the home appliances have been designed for 50Hz frequency. So should I still target 61.5Hz or it can vary for me


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## imran (Feb 25, 2018)

Thanks KRE... Stay Happy and Blessed ...


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## Handyhiker (Sep 29, 2016)

No on the 61.5 hertz. Sorry did not look to see where you were from. 
I have not delt with 50hz generators. I would think however it is similar to to 60hz settings. You generally want your average output as close to what the power company supplies as possable. This would mean you are a little high on your settings. Ours is 60hz, I set mine at 61.5 unloaded and check the full load and try not to have it below 58.5hz. Average load right at 60hz. I would assume your average load should be 50hz. Might set no load around 51 - 52 and see where your loaded hz wind up.


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## KRE (Nov 29, 2011)

Prime mover droop is a percentage of no load(high Idle) to full load speed. No rope start mfg makes anything less that 3% droop prime mover speed controls an most are 5% (or more in the real world) In a 60 hertz world a rope start needs to be set an 62.5 hrz no load an it will droop to 59.5 hz at full load everything working properly. This is all based upon a standard day rating, if the environment conditions are not to std day specs the unit will not tote the rated load. (the mfgs will not tell you this, but it's fact!)
In the 50 hertz world, (most places across the ponds) no load should be 52 hertz an at full load it will droop to 49.5 hertz. 
On both systems this is all based upon a std day running environment, an the engine an all controls being adjusted an operating properly an with a KW (true power load) applied. KVA only tells you about the alternator, KW tell you about the prime mover aka engine.


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## KRE (Nov 29, 2011)

imran said:


> 1. "Does the variation in AC frequency (From 52HZ to 56HZ) harm the other sensitive electrical appliances like CCTV cameras, routers and mobile chargers?
> 2. I run 3 big LED TVs on generator, would this frequency variation be harmful to the LEDs?


The technical,.... most of "your loads" are converting the input A/C to D/C. Therefore in reality the operating speed of the diodes is stepped up a little but not to the point of failure unless your running them 24/7/365 which I doubt you ever will. 
People sometimes say my computer or UPS system will not operate on the genset, that is because the mfg of the computer or UPS has set the window tight. We can make it thru any window but the genset an it controls start getting pricey 
real quick. 
Power generation is not voodoo but some wallets will not open on based upon truth. So some mfgs will not tell you everything, because they're in the selling end. If it burns up most just go but another instead of ever knowing why/truth.


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## motormonkey (Jul 10, 2016)

The switching type power supplies found in most modern consumer electronics are likely to be pretty forgiving of that kind of power input frequency variation. That said, ten percent frequency variation is pretty poor frequency regulation.


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## KRE (Nov 29, 2011)

motormonkey said:


> ten percent frequency variation is pretty poor frequency regulation.


 That all depends upon what your powering. For 40-50 years many farms in this country used PTO gensets that used the Tractor as the prime mover. Most all tractors of those years only have a 10% speed control device on the engine. Those gensets powered everything that was required to run on a farm from milking machines to TV's an radios. The sad part in today's world is most everything is a ED (Edge Designed) which is designed to fail outside of "Very Strict Normal" perimeters. Most all rope start units of today are of this design. Is that because the public will not pay for quality or is that uneducated or both? This has been kicked around in some circles an the bulk in the field feel the later is the correct answer, as most people these days just want to throw money away to correct a simple problem. There are two mfgs who exploit this, one is a price point unit at the very bottom, the other is tied at the top. Both marketing policy's seem to work, as they both laugh all the way to the bank with their product line.


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