Generator Should I change my PTO generator from Bonded Neutral to Floating Neutral?

[schmism]

Usually the larger one's are at the top but I didn't know if there was an electrical reason for this.

If your backfeeding a standard breaker then generally they are positioned as close to the main breaker as possible to facilitate a lockout/interlock device so that neither breakers can be on at the same time. (the only "legal" way to backfeed a panel)

 

[stonypass]

Not sure what I was thinking, I am planning on using an interlock so I'll have to move the breakers on the right side down to make room for the Generator inlet at the top right.

When the house was built in 1996 however, I ran a 2-2-4 line to the barn and put the breakers for it at the bottom left side of the panel since there was open space there. Any reason to move it up as a part of this install?

 

[SPYDERLK]

Not sure what I was thinking, I am planning on using an interlock so I'll have to move the breakers on the right side down to make room for the Generator inlet at the top right.

When the house was built in 1996 however, I ran a 2-2-4 line to the barn and put the breakers for it at the bottom left side of the panel since there was open space there. Any reason to move it up as a part of this install?

Not really. The buss bars in the service panel are usually pretty hefty. Voltage will be higher closer to the top, esp when under heavy loading. Were talkin only a couple hundred millivolts max tho.
larry

 

[JPCjr]

I think you may be getting some bad information here. You should NOT make the changes you suggested. Your generator is configured as a separately derived system and it is not field reconfigurable. Therefore, the only safe way to connect your generator to your premises wiring system is through a transfer switch that switches the neutral. Three pole transfer switches are available. If you modify your generator, you are violating NEC articles 90.7, 110.2, and 110.3.

Portable generators that can be configured as a separately derived system or a non-separately derived system are also available. In these cases, a system bonding jumber is installed for a separately derived system or removed for a non-separately derived system. If the system bonding jumper is removed, the neutral from the premises wiring system must be solidly connected to the generator. A plug and receptacle at the generator is not a solid connection.

One of the problems with making the modifications you are suggesting is that the fault current path during an undgrounded (hot) to equipment grounding conductor (ground) fault between the premises wiring system and generator is not directly back to the source, as it should be. Instead, the fault current would need to flow through the premises wiring system main bonding jumper and back to the generator through the neutral. Also, if you were to ever use the generator as described with the plug in the first picture, the same is true. The fault current would be flowing through the plug. In both of these cases if you ever had a fault the circuit breaker may never trip.

 

[Victory Pete]

I think you may be getting some bad information here. You should NOT make the changes you suggested. Your generator is configured as a separately derived system and it is not field reconfigurable. Therefore, the only safe way to connect your generator to your premises wiring system is through a transfer switch that switches the neutral. Three pole transfer switches are available. If you modify your generator, you are violating NEC articles 90.7, 110.2, and 110.3.

Portable generators that can be configured as a separately derived system or a non-separately derived system are also available. In these cases, a system bonding jumber is installed for a separately derived system or removed for a non-separately derived system. If the system bonding jumper is removed, the neutral from the premises wiring system must be solidly connected to the generator. A plug and receptacle at the generator is not a solid connection.

One of the problems with making the modifications you are suggesting is that the fault current path during an undgrounded (hot) to equipment grounding conductor (ground) fault between the premises wiring system and generator is not directly back to the source, as it should be. Instead, the fault current would need to flow through the premises wiring system main bonding jumper and back to the generator through the neutral. Also, if you were to ever use the generator as described with the plug in the first picture, the same is true. The fault current would be flowing through the plug. In both of these cases if you ever had a fault the circuit breaker may never trip.

As a licensed electrician I agree. Grounding can be very confusing. You should check with your LAHJ (Inspector) before you do anything. Have a look here:Grounding and Bonding of Separately Derived AC Systems | NEC content from Electrical Construction and Maintenance (EC and M) Magazine

VP

 

[DarkBlack]

Shut of you main breaker,Tie in a suicide cord, backfeed a 240v outlet,start her up and be good to go.

 

[TMB1320]

Bonding the gen chassis is for protection against the genny developing a fault where some segment
Of the windings shorts to the iron core. The hot chassis results if it were not bonded. And for the ground loop problem, definitely disconnect the neutral from the mains provided your house neutral
Is bonded to a ground rod, or municipal copper water pipe to the house.

 

[stonypass]

As previously stated, I will be using an interlock and a 50a double pole breaker due to the limitations imposed by a transfer switch.

In my breaker box neutrals and grounds are bonded to a common bus and there is a ground rod on the other side of the wall.
The question is whether or not to leave neutral bonded to ground on the generator, or to isolate neutral from ground on the generator?

Also the cord that came with my generator is 22ft long and 6ga for all four wires.
A nearby hardware store sells 6/3 with ground in a sheath but the ground is 10ga, should the ground be 6ga as well?

I live in a rural area where inspections will not be required, but I'm wondering if I called three electricians would all tell me the same thing?

 

[SPYDERLK]

As previously stated, I will be using an interlock and a 50a double pole breaker due to the limitations imposed by a transfer switch.

In my breaker box neutrals and grounds are bonded to a common bus and there is a ground rod on the other side of the wall.
The question is whether or not to leave neutral bonded to ground on the generator, or to isolate neutral from ground on the generator?

Also the cord that came with my generator is 22ft long and 6ga for all four wires.
A nearby hardware store sells 6/3 with ground in a sheath but the ground is 10ga, should the ground be 6ga as well?

I live in a rural area where inspections will not be required, but I'm wondering if I called three electricians would all tell me the same thing?

The bigger the ground wire the closer the gen chassis will be to true house/earth ground. Still, either way on that short run were talking very small difference in potential possible even at full current capability. You could feel it with your tongue if you leave neutral bonded at gen because the ground would be effectively sharing the load with the neutral. Isolate neutral at the gen as youve described.
larry

 

[JPCjr]

You're asking what is the better of two bad choices. Neither option is code compliant or safe. If you want a safe installation follow the code. I'll be glad to help you if you have questions about how to do that. You may also want to check here: Mike Holt's Forum