# Have 2-120s but no 240



## stuman (Oct 19, 2013)

I have an 8000 watt generator that the 240 is not working. I have tested at the hots coming out of the generator I get 120 from both but together get nothing. I think it something to do with the frequency or the two being on the same wave. Not sure I'm saying that right. But any help would be appreciated.


----------



## aandpdan (Oct 8, 2012)

What model generator?


----------



## stuman (Oct 19, 2013)

Duramax8500


----------



## aandpdan (Oct 8, 2012)

"m not sure if I'm looking at the right schematic - Duromax 8500e?

Does your generator have a 120/240 switch? I'm seeing it on the schematic. How are the breakers? 

You should have 2 duplex 120 volt outlets (4 120 volt outlets total). Each duplex is on one 120 volt leg.


----------



## stuman (Oct 19, 2013)

That's correct. I have gone around that switch. With no luck. Like I said each 120 leg is working but not getting 240 together. So I think the two 120s are on the same wave. But don't know why. Thanks for the help.


----------



## kanoa50 (Oct 6, 2013)

sounds like something wrong internally on the generator since you say you have 120 individually but nothing together, so they are somehow cancelling. 

with 240 you have one leg positive on the sine wave and the other leg 180° from it to equal 208 or 240 between them (depending on a Y or delta transformer), but your not seeing a voltage differential

i know this may only confirm things and not solve your issue. possibly some other guys know generator wiring and can help


----------



## Robert Coats (Nov 10, 2011)

stuman said:


> That's correct. I have gone around that switch.


The switch is necessary to get 240V. 

The generator has two 120V windings (a.k.a., power circuits). When the switch is set to "120" the two windings are connected in PARALLEL, which provides full (maximum) power @ 120V through the 120V receptacles.

When the switch is set to "240" the windings are combined in SERIES. This means they are making 240V through the (usually single) receptacle marked "120/240." 

Here's an example of how it works, for a HONDA generator, and it's likely yours is similar. 









[email protected]
_Caveat: I work for Honda, but the preceding is my opinion alone._


----------



## kanoa50 (Oct 6, 2013)

Great response...i think aandpdan also mentioned the switch too. 

i would remove the switch labeling the wires as i took them off and check it with an ohmmeter.


----------

