Common install issues/troubleshooting for a manual transfer switch?

[owl123]

I had a Generac 6853 HomeLink installed but we are still getting GFCI issues.

Curious for any recommendations here for troubleshooting or things to look out for?

E.g., over on the ICE 150 forums I saw someone mentioned needing to wrap the ground wire in the junction box to avoid a ground fault.

Also, any suggestions for trying to troubleshoot this myself? I’m not looking to do any electrical work myself but I’m open to testing could do to try and track down the problem.

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[P-38]

When I search for that model it takes me to a 22kw generator.

If the switch is not switching the ground from the building ground to the truck ground then most likely the solution would be to disconnect the ground wire from the truck. This is probably most easily done at the back of the inlet plug to the house. You would want the enclosure to still be connected to the house ground wire but the ground on the inlet plug itself would be left disconnected.

 

[Henry Ford]

I ran into an issue with my install. Here's what I wrote when someone else asked how to troubleshoot it.

Someone will tell you to lift the ground on your inlet box. My opinion is you've gone through the trouble of installing the switch so you might as well complete the job.

I've had this exact issue. I'm going to do my best to go through the steps to identify the problem below but it's possible I miss a step since I'm going by memory, which is not good. Be safe. Don't test a hot panel. Assume it's hot until you confirm it's not. You are testing for continuity, not current. Anyway...

The problem is there's a neutral touching ground somewhere when the switch is in the Generator Power position. It's that simple. You need to figure out where that is happening.

1. Make sure you lifted the correct neutral wires from your main panel. It would be an easy mistake to make to reroute the wrong wire, especially if your panel was full, like mine was.

2. Test continuity between the neutral bus and the ground bus in the switch panel with the switch in the Generator Power position. There should be no continuity.

3. If there's continuity between the ground bus and neutral bus in the switch panel, lift individual neutral wires from the neutral bus and test continuity between the individual neutral wire and the ground bus. There should be no continuity.

4. If you identify a circuit with continuity to the ground bus you have isolated the circuit where neutral and ground are touching. Figure out exactly what outlets/lights/etc. are on that circuit and start investigating. Unplug everything on the circuit and test again. If you still can't find it start inspecting outlets, light hookups, and whatever else is hooked up to that circuit. That's how I discovered a miswired fireplace fan.

If you are brave enough to face internet scrutiny, post photos of your installation here. If there's something that's screwed up it will be identified and you can address it.

Good luck! It's frustrating but if you are methodical, thorough, and safe you'll figure it out and be happy with the switch when it's put back together.

 

[Henry Ford]

When I search for that model it takes me to a 22kw generator.

If the switch is not switching the ground from the building ground to the truck ground then most likely the solution would be to disconnect the ground wire from the truck. This is probably most easily done at the back of the inlet plug to the house. You would want the enclosure to still be connected to the house ground wire but the ground on the inlet plug itself would be left disconnected.

Good observation. If it's not a neutral switching transfer switch my advice above is useless.

 

[owl123]

When I search for that model it takes me to a 22kw generator.

If the switch is not switching the ground from the building ground to the truck ground then most likely the solution would be to disconnect the ground wire from the truck. This is probably most easily done at the back of the inlet plug to the house. You would want the enclosure to still be connected to the house ground wire but the ground on the inlet plug itself would be left disconnected.

Good catch, but that was just a typo on my end. Should be Generac 6853. I edited my post above to reflect that.

 

[P-38]

Cool. It is a neutral switching load center. So as @Henry Ford said you might as well finish it.

I would start with turning all 8 breakers in the load center off and then switch over to truck power. If the GFCI trips then the problem is inside the transfer switch, likely the neutrals are not wired per the diagram. It's odd to switch neutrals in US wiring so it's a little different than many electricians I know are used to, unless they install generator transfer switches often.

If the truck GFCI did not trip then turn on the breakers one at a time until you find the offending circuit, following what Henry Ford quoted.

 

[Henry Ford]

Cool. It is a neutral switching load center. So as @Henry Ford said you might as well finish it.

I would start with turning all 8 breakers in the load center off and then switch over to truck power. If the GFCI trips then the problem is inside the transfer switch, likely the neutrals are not wired per the diagram. It's odd to switch neutrals in US wiring so it's a little different than many electricians I know are used to, unless they install generator transfer switches often.

If the truck GFCI did not trip then turn on the breakers one at a time until you find the offending circuit, following what Henry Ford quoted.

This isn't quite right. Individual breakers switch the hot wire on or off. If a neutral is touching ground anywhere in any of the circuits in the switch panel it will trip the truck GFCI regardless of individual breakers switch position. This is not intuitive, which is a big part of the reason why it trips up so many people, myself included.

@owl123, read and follow my troubleshooting steps closely. Once you understand why you are doing each step it will make sense. Ask questions here. It's been awhile but I think I remember enough to discuss it intelligently. @Maquis seems to legitimately know what he's talking about. There are others too. You'll figure it out.

 

[Maquis]

This isn't quite right. Individual breakers switch the hot wire on or off. If a neutral is touching ground anywhere in any of the circuits in the switch panel it will trip the truck GFCI regardless of individual breakers switch position. This is not intuitive, which is a big part of the reason why it trips up so many people, myself included.

@owl123, read and follow my troubleshooting steps closely. Once you understand why you are doing each step it will make sense. Ask questions here. It's been awhile but I think I remember enough to discuss it intelligently. @Maquis seems to legitimately know what he's talking about. There are others too. You'll figure it out.

This is correct.

I will add that not all GFCIs incorporate the continuous neutral to ground sensing like our trucks apparently do. Some will only trip once current starts to flow.

 

[Henry Ford]

This is correct.

I will add that not all GFCIs incorporate the continuous neutral to ground sensing like our trucks apparently do. Some will only trip once current starts to flow.

@Maquis is like Beetlejuice; when you call his name he appears, except instead of trying to trick you into marrying him he provides useful and thoughtful information.

 

[P-38]

Ok. I'm used to home or industrial setting where the GFCI is looking for a difference in flow, no load = no trip. Did not realize our trucks were so fancy to monitor a connection. Would make troubleshooting harder but still do able.

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