AC Breaker Panel Question

[kazetsukai]

Originally Posted by JDOnTheGo

I guess I don't understand your switch. It makes no sense to me to have two sets (of four) wires coming out of it and going to the panel. That is not a typical transfer switch.

I use one of these. It has two sets of connections: A+B, C+D.


If you wire in the inverter to A and shore to C, both B and D need to go to the panel.

[kazetsukai]

Originally Posted by dj2109

My ONLY QUESTION is can I fit two hot wires in one terminal on my AC panel? One through the top and one through the bottom? Isn’t that how a subpanel is wired?

How I wired that switch:

There are four sets of four conductors A, B, C, D.
The switch has three positions:

Position 1: A connects to B.
Position 0: Nothing is connected.
Position 2: C connects to D.

I ran my inverter to A, shore to C. I ran in the same box as the switch:

• A connection bridging B to D
• A connection from D to the main breaker panel.

No, its not your typical transfer switch. Its rated higher than the application (600V at 65A IIRC) and should work, however.

[dj2109]

How exactly would I bridge B to D?

Also does my AC panel need to be grounded to the chassis? If so would I use the green grounding screw somehow?

[dj2109]

Can you please check out my diagram and tell me if that will work?

[dj2109]

Here’s what I’ve done:

[dj2109]

Please don’t make fun of how ugly it is

[kazetsukai]

Entry into the load center should use something to keep the wires from moving around. Over a period of time, vibration could start to breach the insulation and cause a short.

Something like:

https://www.homedepot.com/p/Halex-3-...0511/100133208


And while I suppose the way you've done it works, I'd only have one cable from the switch, bridging B and D at the switch (running 3-4 inch cables between B and D, and then tap off D to go to the load center) for organizational purposes. I think that's all ultimately up to you, what you have is functional.



Another suggestion: Use a PVC weatherproof conduit box for the switch instead of wood? Home Depot may sell a few that are the right size.


Looking good I'd say so far.

[dj2109]

Awesome!!!!!! Thanks for the input!!!!!

[dj2109]

Also, do I need a to ground my load center?

Use 2/0 to wire ground bar to negative bus bar? Or is that mixing AC and DC?

[Rock-N-Ruth]

Originally Posted by dj2109

Also, supplier says I can use 10AWG.......... I’m scared

#10 gauge is fine coming from your inverter to the transfer switch and from the transfer switch to your breaker box.
From your breaker box to circuits generally you can use 14 gauge for lighting circuits, 12 gauge for your general purpose outlets including solitary circuits for air conditioning up to 20 amps.
Our system does the same thing except I'm frugal so the transfer is manual. I have a shutoff for solar 24v inverter, solar 12v inverter, and shore. Two off, one on.
We run 8000btu a/c, two 4.5cf fridges, 7.5cf deep freeze, 50 inch TV, microwave, instant pot, phone chargers and fans. No problems.

[Doktari]

Did you find the answers to your questions?

[Rwnielsen]

"My ONLY QUESTION is can I fit two hot wires in one terminal on my AC panel? One through the top and one through the bottom? Isn’t that how a subpanel is wired?"

NO. A transfer switch has one output to the panel. It can have several inputs. On your selector switch, be absolutely certain that it breaks before makes and there is no possible connection between shore power, inverter or generator. A transfer switch opens one connection before making another.

[Rwnielsen]

Originally Posted by dj2109

Here’s what I’ve done:

You need to take that apart before you hurt yourself. Whatever your source is will back feed the other. If your inverter is on it will make your shore power cord hot. You don't want a phase to phase short. Things blow up, people get hurt.

[flattracker]

Hello,
I am using a mostly off-the-shelf solution. I purchased a Siemens electrical panel and coupling brackets that will turn the opposite breaker to off when the first breaker is turned on. By using two electrical panels or one with the bus bars cut in the middle and two pairs of breakers with the couplers one can safely switch between outside power, inside power, and when running on inside power, switch between generator or inverter power. My outside power connection will have 50 Amp capacity at 240 VAC. My generator supplies 30 Amps at 240 VAC, with neutral and ground. Note: I don't plan on any 240 VAC appliances yet, but the capability is there.

When you have 240 VAC with neutral, you have 120 VAC on one leg and 120 VAC on the other. If both legs of your AC power are drawing the same amount of current, the current flow through neutral is Zero Amps. When the current flow through each leg is different, the current flow through neutral is the difference in current flow between the two legs. In my case with a 50 AMP 240 VAC from outside power, the most current flow possible through neutral is 50 Amps. Since my generator is rated for 30 Amps, the most current flow through neutral when running from generator is 30 Amps.

Note: Even through neutral and ground are connected in the electrical panel, ground is very important. Always wire your RV using grounds.

The mechanical coupling between circuit breakers is readily available. My current project is using Siemens, but Square D also makes a similar device that works with their breakers. In fact for my first Crown, I purchased an "RV electrical panel" setup with the coupled breakers.

For a 50 Amp service do use 6 gauge wire.
For a 30 Amp service do use 10 gauge wire.
I only use copper wire.
Attached is a picture of my panel with the Siemens devices installed. The 40 amp breakers are to be replaced with 50 amp Breakers.

[kazetsukai]

Originally Posted by Rwnielsen

You need to take that apart before you hurt yourself. Whatever your source is will back feed the other. If your inverter is on it will make your shore power cord hot. You don't want a phase to phase short. Things blow up, people get hurt.

He's using a changeover switch. Read my previous posts in the thread for clarification.



The changeover switch is 4 sets of 4 poles (A, B, C, D), with 3 positions. 1 connects A to B. 0 all are disconnected. 2 connects C to D. Both wires in the panel feed to positions D and B on the changeover switch, there is no possibility of back feeding.


I have an identical setup.

[Rwnielsen]

Fair enough. Im not comfortable with 2 feeds to a panel but if that works so be it.