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Onan Generators

Onan 7.5JB - Wiring


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  #11  
Old 01-08-2017, 04:13:12 PM
kiteoregon kiteoregon is offline
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Default Re: Onan 7.5JB - Wiring

Yes this is connecting to a house.

L1 = hot leg, black
L2 = hot leg, red
L0 = common, white

I still don't have any power output. I will read up and try to figure out what controls the output power. Once it's running, do i need to bring up idle or do anything to engage the load side? From the only gauge i have it appears to be charging the battery.
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  #12  
Old 01-08-2017, 04:31:50 PM
Augie1 Augie1 is offline
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Default Re: Onan 7.5JB - Wiring

The generator should be running at 1800 RPM. Never apply or disconnect a load unless it is running At rated speed or you could see smoke. If it is running at 1800 you should have voltage close to 120/240 volts.
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  #13  
Old 01-08-2017, 05:22:29 PM
kiteoregon kiteoregon is offline
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Default Re: Onan 7.5JB - Wiring

How do i determine what RPM the engine is running, is there a voltage to check or supplemental gauge i can get?
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Old 01-08-2017, 05:30:30 PM
Dale Russell Dale Russell is offline
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Default Re: Onan 7.5JB - Wiring

Get your self a "KILL-A-WATT" Meter. It will read Volt, Amps Hrtz. & etc. They are a very good investment with a generator of any kind.

http://www.newegg.com/Product/Produc...82E16882715001
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Old 01-08-2017, 06:23:26 PM
len k len k is offline
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Default Re: Onan 7.5JB - Wiring

Quote:
Originally Posted by kiteoregon View Post
I still don't have any power output. I will read up and try to figure out what controls the output power. Once it's running, do i need to bring up idle or do anything to engage the load side? From the only gauge i have it appears to be charging the battery.
Engine supposed to run at ~ 1800 rpm at all times, no-load and full load.
Rpm controls hz, electronic voltage reg on top of control box controls voltage.

IF bat charging windings are making power so too should your "120" VAC main windings. The voltage reg powers the rotor electromagnet which sweeps magnetic feild thru both "120" and bat charging windings.
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  #16  
Old 01-29-2017, 03:15:52 PM
kiteoregon kiteoregon is offline
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Default Re: Onan 7.5JB - Wiring

On further investigation, if i place my volt meter on AC and connect to L1 with the red, and common with black, i only get 2.30 volts once warmed up. If i twist the idle screw on the carb i the voltage will also rise.

Where should i look / test next?
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  #17  
Old 01-29-2017, 05:13:14 PM
Augie1 Augie1 is offline
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Default Re: Onan 7.5JB - Wiring

So, your saying when you first start it (Cold) you have the the 120/240 volts until it warms up.
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  #18  
Old 01-29-2017, 07:13:37 PM
kiteoregon kiteoregon is offline
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Default Re: Onan 7.5JB - Wiring

I never get a voltage higher then 2.30 volts (cold or warm) unless i twist the idle screw then i can see a small rise in voltage.
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  #19  
Old 01-29-2017, 07:14:14 PM
Max Thompson Max Thompson is offline
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Default Re: Onan 7.5JB - Wiring

Quote:
Originally Posted by kiteoregon View Post
i only get 2.30 volts once warmed up. If i twist the idle screw on the carb i the voltage will also rise.
"2.30" volts or 230 volts?

Use the governor adjustment screw to raise RPMs and voltage, not the idle stop screw.
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  #20  
Old 01-29-2017, 07:36:48 PM
kiteoregon kiteoregon is offline
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Default Re: Onan 7.5JB - Wiring

Thats a good point, i don't know if my MM is putting a decimal in there. I will check a known 110 to verify. Which is the governor adjustment screw?
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