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I think this the process
1 remove the neutral/ground link
2 use a neutral/ground plug when not connected to the house service
3 remove neutral/ground plug when connected to the house service.
This should satisfy the generator for a linked neutral/ground condition for whatever reason it needs it.
 

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I think this the process
1 remove the neutral/ground link
2 use a neutral/ground plug when not connected to the house service
3 remove neutral/ground plug when connected to the house service.
This should satisfy the generator for a linked neutral/ground condition for whatever reason it needs it.
No reason for that not to work okay! 👍
 

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Yes there does seem to be a problem running this generator without a neutral/ground link my regulator has apparently failed without a link of some kind. In my case I removed the link and tried to start on NG and it would not start as the gas shut off solenoid was not getting power.
Firman said the regulator has failed? Which means just cranking should generate sufficient Voltage to hold in the gas lock lockout solenoid. They are sending me a replacement solenoid which makes me concerned that is after all a design issue of some kind.
 

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I removed the link and tried to start on NG and it would not start as the gas shut off solenoid was not getting power.
Yes, I had mentioned that way back in post #17...
I agree, although it looks like that 12V supply is used for the fuel cut solenoids, too...
makes me concerned that is after all a design issue of some kind.
Yes, I'm going with that... Removing the bond should not be causing these issues.
 

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Made an error it's the regulator that they are sending me which makes more sense
The voltage regulator right?

If you were using the process you posted in #83, then you had an N-G bond. So something's not making any sense.

If there is a design issue causing a problem with removing the N-G bond, then it must not be consistent across the units being shipped because other people are not having this problem.
 

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Is there a circuit diagram for the tri fuel control board for the Firman tri fuel gen . Not in the manual and the service tech dosnt seem to have any ideas?
Anybody?
This is what my manual shows for the Firman T07573 and is also available on www.firmanpowerequipment.com.

I recently purchased the T07573 and will be testing by removing the Neutral Bonding at the generator and confirm the LP still works or not.
 

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This is what my manual shows for the Firman T07573.....
Yes, that is similar to the OP's T07571.

The mystery seems to be that some people are having the voltage regulator (aka intelligent rectifier) burn up when the N-G bond is removed. Others seem to have no issue. What might clear it up is finding a schematic of the dual fuel module.
 

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This is what my manual shows for the Firman T07573 and is also available on www.firmanpowerequipment.com.

I recently purchased the T07573 and will be testing by removing the Neutral Bonding at the generator and confirm the LP still works or not.
I removed the white jumper wire at the end of the "alternator" that was documented above and tested to make sure the Green wire ground was no longer bonded to Neutral.
Connected to NG source and set the switch to NG ( not Propane ), turned the front switch to NG/Propane ( not gasoline ) and pressed start. At first, I thought it was not going to work as it cranked for 5-sec or more. On the second try and choke ON, it fired up and ran just fine - NO SMOKING PARTS !

Looking back, the schematic does not show NG that I could see because electrically there is no difference between the two. The only thing you do depending on if the source is NG vs Propane is to turn a valve that is after the fuel regulator and before the carburetor. I would say this is another successful change from bonded Neutral to Floating so I can now attach to the House main and only bond neutral at the panel. I am not using a transfer switch, but a mechanical interlock that only allows you to energize the panel from the generator source if the MAIN is OFF. The interlock also makes you turn off the Solar breaker too so if during the day my solar panel will not turn back on when the generator energizes the panel.
 

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I removed the white jumper wire at the end of the "alternator" that was documented above and tested to make sure the Green wire ground was no longer bonded to Neutral.
Connected to NG source and set the switch to NG ( not Propane ), turned the front switch to NG/Propane ( not gasoline ) and pressed start. At first, I thought it was not going to work as it cranked for 5-sec or more. On the second try and choke ON, it fired up and ran just fine - NO SMOKING PARTS !

Looking back, the schematic does not show NG that I could see because electrically there is no difference between the two. The only thing you do depending on if the source is NG vs Propane is to turn a valve that is after the fuel regulator and before the carburetor. I would say this is another successful change from bonded Neutral to Floating so I can now attach to the House main and only bond neutral at the panel. I am not using a transfer switch, but a mechanical interlock that only allows you to energize the panel from the generator source if the MAIN is OFF. The interlock also makes you turn off the Solar breaker too so if during the day my solar panel will not turn back on when the generator energizes the panel.
Glad to hear this worked. I had an interlock system installed last year unbeknownst to me the issue of having a NG bond. After doing a lot research I found this thread.
 

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Today I tried removing N-G bond on my firman T07571 and did not seem to have issues. I mean the generator started as normal, I let it run for 15 mins and did not see any smoke or anything.

The process followed is similar to

i am not sure why one of the members faced issues with bridge rectifier burning. But I did not see any of these issues.
 

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I lifted my NG bond on my T07571 several years ago to be able to run it through my service panel with an interlock kit. I ran it that way for about 30 hours all together through a power outage after a hurricane in 2019. No issues at all.
 

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Good to know. I think the concern has been that the electronics that control being able to use LPG or CNG. Would you be able or have you tested using either of those fuel sources?
I actually have used the genny on LPG since then, but that was under no load. Strictly testing that it operated on propane. I ran it for at least 5 minutes. I have also used it since then with gasoline without problem.
 
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