Installed Transfer Switch in House

[Gros Ventre]

Re: the neutral-ground bonding in the truck: Ford chose to set up the truck for contractors working at a site without utility power. The neutral-ground bonding is a requirement of OSHA not the NEC. Opening the ground wire between the house and the truck does allow the truck's system to power the house because it no longer senses the neutral-ground bonding in the house. However, this then leaves the truck frame & components without a path to ground. I believe that is a bad, bad idea even if it seems to work. I also believe it is not NEC compliant.
The neutral switching panel discussed above is effectively a means of opening up the neutral-ground bonding in the house. It leaves the ground path for both the truck and the house intact. However these appear to set you up with an "emergency" panel that limits powered house circuits. The 7.2 kW generator in the truck has all the power you need for the full house.
Recall there are four things needed to be safe and compliant with the NEC: 1- an interlock between the generator input and the utility line input; 2- a house input cable box that has a male connection; 3- not using a male-male cable from generator to house (which is why you need #2); and 4- a 4 wire cable connecting the generator to the house of sufficient rating for the generator (eg two hots, 1 neutral and 1 ground wire).

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[Suprman810]

I installed the Reliance PB30 inlet box and ran the two hots to a new 30amp 240v breaker. Then installed the interlock. I had to disconnect the ground in the inlet box to prevent ground fault in truck. It works great, but referencing Gros Venture’s NEC code drop (any many other thread comments) it seems that I’m in violation.

Can someone help me understand why this is dangerous. Not challenging it just want to understand.

 

[UGADawg96]

I installed the Reliance PB30 inlet box and ran the two hots to a new 30amp 240v breaker. Then installed the interlock. I had to disconnect the ground in the inlet box to prevent ground fault in truck. It works great, but referencing Gros Venture’s NEC code drop (any many other thread comments) it seems that I’m in violation.

Can someone help me understand why this is dangerous. Not challenging it just want to understand.

If you go back and read the comments, it's been stated multiple times in this thread.

 

[Hullguy]

I installed the Reliance PB30 inlet box and ran the two hots to a new 30amp 240v breaker. Then installed the interlock. I had to disconnect the ground in the inlet box to prevent ground fault in truck. It works great, but referencing Gros Venture’s NEC code drop (any many other thread comments) it seems that I’m in violation.

Can someone help me understand why this is dangerous. Not challenging it just want to understand.

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[Gros Ventre]

It's dangerous since it leaves the truck frame, ground, etc, unconnected to ground. The issue remains that Ford has set up the truck as a bonded neutral-ground system. Then when it senses the neutral-ground bond in your house, it shuts down the generator because of the ground. There are two fixes for this: 1-You can set up the house with a neutral switching arrangement -or- 2-Ford can design the Powerboost to change operation to a floating neutral. With the floating neutral there is only one neutral-ground to be sensed thus allowing the powerboost to power up an entire house. Note that Ford setup the 2.0 kW generator in non-Powerboost trucks as a floating neutral, so they know how to do it.

 

[n8dgr8]

I'll add this comment to my discussion above. I already have a floating neutral generator, so I don't hook my powerboost to the house. I am asking these questions out of genuine curiosity to understand (I'm a chemical engineer, not an electrical) and also to try and provide an easier solution to others who might need it.

Computer science, not an electrician, or an electrical engineer either... The danger is most likely from someone removing the ground for a bonded generator setup and later someone else using the same wiring for a non-bonded generator setup (without reconnecting the ground in the connecting cable). The truck is protected with GFI and the double bonding of the truck ground to neutral and the again the panel neutral bonded to ground again. Even when you remove the ground in the connecting cable, the truck is still connected to your house ground through all of the bonding. This should be easy to verify with a multimeter.

For the un-bonded floating neutral generator, it is really important to ground the generator. If someone touches the generator when the generator is outside in the pouring rain, they could get a big shock. Having the ground connected means wayward current is going to take the path of least resistance through ground instead of your wet hands and feet.

 

[Suprman810]

It's dangerous since it leaves the truck frame, ground, etc, unconnected to ground. The issue remains that Ford has set up the truck as a bonded neutral-ground system. Then when it senses the neutral-ground bond in your house, it shuts down the generator because of the ground. There are two fixes for this: 1-You can set up the house with a neutral switching arrangement -or- 2-Ford can design the Powerboost to change operation to a floating neutral. With the floating neutral there is only one neutral-ground to be sensed thus allowing the powerboost to power up an entire house. Note that Ford setup the 2.0 kW generator in non-Powerboost trucks as a floating neutral, so they know how to do it.

Thank you for the replies. where is the danger. In the house, at the inlet box, or at the truck?

when main power is supplied to the home they bring in 3 cables, correct? 2 hots and a non-hot. Isn’t this the same as my setup.

 

[BLoflin]

The safety issue of deleting GND from your cable from PB has been discussed ad nausem, including by me.

Let me try briefly once more.

To poke at n8dgr8 a little (he's the CS major vs EE major), grounding (and bonding) is not a binary situation, when there is an actual safety/failure situation. So it is NOT a matter of the circuit is grounded (somewhere) so we are good. Harm from active power sources is an analog function.

In a fail situation the current will take the least resistance path and it doesn't take long to be deadly. So if you are in the circuit (because of a fail, either in PB itself, or something connected to it) and you are the least resistance path, it doesn't matter there is another path somewhere to GND, you will get the initial amperage. That is what the NEC codes and other practices are trying to insure they will prevent.

 

[Suprman810]

The safety issue of deleting GND from your cable from PB has been discussed ad nausem, including by me.

Let me try briefly once more.

To poke at n8dgr8 a little (he's the CS major vs EE major), grounding (and bonding) is not a binary situation, when there is an actual safety/failure situation. So it is NOT a matter of the circuit is grounded (somewhere) so we are good. Harm from active power sources is an analog function.

In a fail situation the current will take the least resistance path and it doesn't take long to be deadly. So if you are in the circuit (because of a fail, either in PB itself, or something connected to it) and you are the least resistance path, it doesn't matter there is another path somewhere to GND, you will get the initial amperage. That is what the NEC codes and other practices are trying to insure they will prevent.

Don’t act so inconvenienced! You love explaining things else you wouldn’t be here. Thank you!

 

[pkinneb]

So i'm curious is this something the market place can solve with a new product?

 

[Gros Ventre]

In one of the posts above it the was asked why there are only three wires coming in from the line input. That is because the utility only supplies the two hots & neutral. The ground occurs at your house. Keep in mind that the NEC specifies that the gound and neutral wire be bonded at only one place. Commonly in the main panel, but some utilities specify that bonding be outside in their input (or meter) box. That grounding point likely has two 6' copper rods driven into the ground/earth. They are then connected into the house grounding wiring via, commonly, 6 gauge bare copper wire. The NEC specifies ony one neutral-ground bond since it appears that with more than one bonding point circulating currents can build up, sometimes to dangerous levels. So, do the utilities have a neutral-grond bond? In my neck of the woods the utility requires that bonding outside in the meterbox. I infer from that that this is then their "system" bonding...

 

[OddManOut]

For those with the Generac 6852, do you have a loose/disconnected orange wire at the top of the device (see photo)?

The other side appears to connect to what I think is the motor/servo that swaps the unit back and forth from UTILITY to GENERATOR. When I press my front panel switch, nothing happens. If I manually switch from UTILITY to GENERATOR, the unit works fine.i suspect that wire came loose, but I don't see where to attach it.

 

[Hullguy]

For those with the Generac 6852, do you have a loose/disconnected orange wire at the top of the device (see photo)?

The other side appears to connect to what I think is the motor/servo that swaps the unit back and forth from UTILITY to GENERATOR. When I press my front panel switch, nothing happens. If I manually switch from UTILITY to GENERATOR, the unit works fine.i suspect that wire came loose, but I don't see where to attach it.

It plugs into the switch on the cover

 

[OddManOut]

It plugs into the switch on the cover

I do have an orange wire attached to the panel. It's part of the 6-pin plug - not a solo wire.

 

[Hullguy]

I do have an orange wire attached to the panel. It's part of the 6-pin plug - not a solo wire.
it goes on the terminal just under the brown wire

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