Generac GP7000E Generator outputting only 110v

Hammermechanicman

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See if you can find a 35uf cap for it and set the RPM so it runs at 62Hz no load.
 

oldlawnguy

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See if you can find a 35uf cap for it and set the RPM so it runs at 62Hz no load.
Star picked up on the wire diagram Rev E it called for a 47uf cap, yet the replacement part # lists 28uf.

Should I try finding a 47uf cap and do the same test?

Thanks!
 

ILENGINE

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Came across this little tidbit in the Generac service manual

NOTE: The voltage of a brushless capacitive discharge generator will start low and increase as load is applied So the 110 volts may be normal until a load is applied.
 

StarTech

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You got to put that torch out when not in use....And never try yo do a haircut with one. <lol>

But here is some general info about brush-less alternators.
1667305856923.png
This would that you just might need a slightly larger cap mounted remotely. You can parallel say a 5 uF capacitor temporarily for test purposes. Just make whatever you use is non-polarized version.
Polarized version will explode; sometimes dangerously. I have had some to send shrapnel all over the shop. One took a week to piece enough together to find out what size it was.
 

oldlawnguy

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Came across this little tidbit in the Generac service manual

NOTE: The voltage of a brushless capacitive discharge generator will start low and increase as load is applied So the 110 volts may be normal until a load is applied.
Interesting ILENGINE. I'm going to put a load on it and then measure AC voltage. Neighbor was testing with a LED lightbulb and stated it flickered and then blew out. He tried and Alexa device and said that blew out too.

I've seen low fat LED bulbs flicker on regular power so that probably not a sizable load or good test.
 

oldlawnguy

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You got to put that torch out when not in use....And never try yo do a haircut with one. <lol>

But here is some general info about brush-less alternators.
View attachment 62705
This would that you just might need a slightly larger cap mounted remotely. You can parallel say a 5 uF capacitor temporarily for test purposes. Just make whatever you use is non-polarized version.
Polarized version will explode; sometimes dangerously. I have had some to send shrapnel all over the shop. One took a week to piece enough together to find out what size it was.
Thanks Star useful info from you and ILENGINE. Was hoping to get some info from the Pro manual side as Generac is pretty much closed to DYI.

I guess a better way to test a brushless is to connect it to an inlet to your house and then turn on some breakers and then measure AC voltage.

My generator is older and has brushes so not an apples to apples comparison. Your catch on the 47uf drawing .vs 28uf replacement part is like a 60% boost. Not sure if it's a cut and paste typo or an actual phase in ECO. If there was a service bulletin on a FCO for this model that would be interesting too.

Thanks for the above info.
 

ILENGINE

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Thanks Star useful info from you and ILENGINE. Was hoping to get some info from the Pro manual side as Generac is pretty much closed to DYI.

I guess a better way to test a brushless is to connect it to an inlet to your house and then turn on some breakers and then measure AC voltage.

My generator is older and has brushes so not an apples to apples comparison. Your catch on the 47uf drawing .vs 28uf replacement part is like a 60% boost. Not sure if it's a cut and paste typo or an actual phase in ECO. If there was a service bulletin on a FCO for this model that would be interesting too.

Thanks for the above info.
I would connect the voltage meter to one outlet on the generator and then plug a drill. angle grinder, etc into the other outlet and see what the voltage is under load.
 

oldlawnguy

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I would connect the voltage meter to one outlet on the generator and then plug a drill. angle grinder, etc into the other outlet and see what the voltage is under load.
(y) yes was planning to do drill, extra hair dryer etc.

I was implying that the master electrician who installed the 30A inlet/gentran switch would have tested via connecting to inlet and e.g. turn on the breaker to garage and test some stuff with neighbor.

I'm surprised how a master electrician would not understand how brushless/brush/inverter gas generator all differ and work.

Thanks
 

oldlawnguy

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(y) yes was planning to do drill, extra hair dryer etc.

I was implying that the master electrician who installed the 30A inlet/gentran switch would have tested via connecting to inlet and e.g. turn on the breaker to garage and test some stuff with neighbor.

I'm surprised how a master electrician would not understand how brushless/brush/inverter gas generator all differ and work.

Thanks
OK fellas here is what I measured:

I also checked the entire distribution box wire connections from generator:

No load measurements: constantly fluctuating between 107-112v 61.2-62.1 Hz
Running Drill :106-110V
Running 1500w small desk space heater: 111-113v

Something is wrong with this puppy, maybe diodes, but I think I'm gonna give back to neighbor and recommend he go get that inverter generator he's eying.

I learned a ton here on brushless .vs brush generators and want to thank Star, ILENGINE and Hammer for helping this DYI stiff learn some things. Hopefully this thread can help someone else too.

You guys are the best!
 

Hammermechanicman

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An inverter genset or one with a AVR would probably be a better choice for power backup purposes.
 
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