Generator tripping 240v circuit breaker

[Sunstar]

Heard Honda Gens are really good and at a pretty decent price for what its worth. awesommeeeee!

[inetdog]

T

So here is the BIG QUESTION. WHY DID YOU RUN L1 and L2 to the Receptacle? All it needed was one of them and leave the TAB in.

it is commonly done on small generators to provide two full current 120V outlets using one receptacle device.

[Logan005]

I am guessing to maximize the output capacity, most generators I have seen run specific power to each plug.

[Sunking]

Thanks for the great info guys but i'm 99.9% sure I know the problem. I replaced the 120v duplex outlet because it was cracked. Didn't realize the duplex tab needed to be broken on the hot screws. I dug the old outlet out of the trash and sure enough the tab was broken on it. So when I reset the 240v circuit breaker L1 and L2 were shorting together..

That would do it but means you wired it incorrectly.

When you buy a receptacle it can either be used as a standard 120 VAC receptacles or Multi-Wire Branch receptacle. They are wired differently. Using them as Multi-Wire is rare.

In a standard connection you just run 3-wires, L-N-G and leave the Tab in connecting the two halves together.

Multi-Wire you must use a Ganged Breaker, and Remove the Tab connecting th etwo halves together. You run 4-wires (L1-L2-N-G) L1 supplies power to 1/2, and L2 to the other half. If you do not remove the tab, you get BANG.

So here is the BIG QUESTION. WHY DID YOU RUN L1 and L2 to the Receptacle? All it needed was one of them and leave the TAB in.

[hammick]

Thanks for the great info guys but i'm 99.9% sure I know the problem. I replaced the 120v duplex outlet because it was cracked. Didn't realize the duplex tab needed to be broken on the hot screws. I dug the old outlet out of the trash and sure enough the tab was broken on it. So when I reset the 240v circuit breaker L1 and L2 were shorting together.

Looks like I got a sweat deal on a nice generator with a Honda GX160 motor and idle control. I have never seen a carburetor and fuel lines so clogged (I think I'll give up bacon). I spent 40 minutes unclogging the carburetor and then realized the main jet was corroded in. Had I know a new carb was only $10 on Amazon I would have started there first.

I don't know how they can produce and sell carbs for $10. Damn Chinese. Love em and hate em.

[inetdog]

My take is that since the generator runs and delivers power on all of the 120V outlets (probably half on L1 and half on L2) but blows the 240V breaker immediately on resetting it, even with no load:
The problem is not in the generator windings, or else the two 120V circuits would not be working.
The problem is not in the generator windings because that would not blow a breaker connected to the output ends of those windings.
The only place left, if the breaker itself is not defective, is in the wiring between the breaker and the 240V output connector.
Careful inspection of that wiring should show the problem. If not, the disconnect both hot leads at the receptacle and at the breaker and get out the ordinary ohmmeter again. If no fault is found with the 1-9 volts that the ohmmeter uses, then you will need to megger those wires and the connector.

[Sunking]

You cannot test the generator windings with an Ohmeter. You should see continuity, very low reading However you might get a clue. Take a reading between L1/Neutral and L2/Neutral. They should be equal.

First thing I would look for with an Ohmmeter is continuity From L1 and L2 to the generator frame aka ground. Should be open circuit. Sounds like you might have a winding shorted out to the generator frame.

What you really need to test with is a Megar aka high voltage ohmmeter.

[hammick]

I am rehabbing a Coleman Powermate 3500w Generator (new carb, fuel lines, plug, air filter, valves adjusted, etc). It's running great. 120v outlets work fine and it has idle control which is working.

There is a problem with the 240v circuit. The generator is tripping the circuit breaker with no loads attached. When I reset the 240v circuit breaker on the Genny it tries to rev up and bogs down like it is overloaded even though nothing is plugged in.

With the generator off I am getting continuity between L1 and L2 and also between L1 and neutral and L2 and neutral. Is my continuity test normal? If so, what else should I be looking for?

FYI neutral is not bonded to ground on this Generator.

Thanks for any help.