Few electrical questions before wiring up

[chiggins]

I'm very close to installing my electrical system, I just have a few questions I'd like to get figured out before I start wiring everything together.


1. I'd like to have a breaker between my solar panels and solar charge controller, for 1) in case something wants to blow up, and 2) so I can disconnect power to service the charge controller. Could someone recommend to me what I'd need to buy in order to accomplish that? I'll have max 44A flowing down, so probably a 50A breaker. And then a box to hook it and wire it into?

2. I bought a 60A box and a 50A breaker for my 50A shore inlet, pictured here. How do I wire up the two hot legs, neutral, and ground for this?
3. I know this is a hot topic, but how do I ground my system? I've seen various opinions everywhere and cannot make heads or tails of it. Do I have a common ground going from my negative bus bar down to the chassis of my bus? Is that appropriate? Or do other things need to get grounded elsewhere or separately.



I think that's all that I have right now. Let me know if something doesn't make sense or if I need to clarify my questions. Thanks!

[kazetsukai]

Originally Posted by chiggins

1. I'd like to have a breaker between my solar panels and solar charge controller, for 1) in case something wants to blow up, and 2) so I can disconnect power to service the charge controller. Could someone recommend to me what I'd need to buy in order to accomplish that? I'll have max 44A flowing down, so probably a 50A breaker. And then a box to hook it and wire it into?

What you're looking for is a PV Combiner box. They come with breakers built in and some can even be installed rooftop.

https://www.amazon.com/s?k=outdoor+P...ref=nb_sb_noss

Originally Posted by chiggins

2. I bought a 60A box and a 50A breaker for my 50A shore inlet, pictured here. How do I wire up the two hot legs, neutral, and ground for this?

That is a double-pole breaker for 240v service. Connect shore red/black to the screws on each side of the breaker, and then to the neutral bus at the top, then run from the double-pole breaker to the main panel hots.

Ground can pass through this box, and should probably be screwed into the box somewhere (circled). I used a box like that for my mini split. See my >1000 word answer below.

Originally Posted by chiggins

3. I know this is a hot topic, but how do I ground my system? I've seen various opinions everywhere and cannot make heads or tails of it. Do I have a common ground going from my negative bus bar down to the chassis of my bus? Is that appropriate? Or do other things need to get grounded elsewhere or separately.

AC - Ground exists for the purpose of tripping safety equipment/GFIs. Its probably a good idea to run ground to the chassis, or to any metallic surface you don't want AC current running through. You need something downstream of the ground to trip for it to be useful. In your kitchen, that's the GFI outlet on the wall.


DC- Negative to chassis is common for both the bus batteries and "house" bank. This is what I like to do:


All DC appliances run two wire to the DC fuse panel, and the DC fuse panel(s) connect negative to chassis. There's more to that picture- DC breakers, etc, but that's another discussion.

I'm not an electrician, I'm just some dude that built something that works. Keep in mind, that can happen by accident.

[chiggins]

Originally Posted by kazetsukai

What you're looking for is a PV Combiner box. They come with breakers built in and some can even be installed rooftop.

https://www.amazon.com/s?k=outdoor+P...ref=nb_sb_noss

I looked into one of those, but then I saw this YouTube video, figured I'd go this route:

https://www.youtube.com/watch?v=8Moju-qyNas

I'd just need to have a box and circuit breaker down line, I'm just not super entirely sure what I'd need, ya know? Definitely just DIY.

Originally Posted by kazetsukai

That is a double-pole breaker for 240v service. Connect shore red/black to the screws on each side of the breaker, and then to the neutral bus at the top, then run from the double-pole breaker to the main panel hots.

Ground can pass through this box, and should probably be screwed into the box somewhere (circled). I used a box like that for my mini split. See my >1000 word answer below.
Attachment 42173

I'm not entirely sure I follow the wiring for the ground wire. Is it just screwed into the box using a ring connector? Is that the end of the ground there? Or another wire that's screwed in to the box, then screwed into the chassis? Or screwed into the box, and then from there into my inverter? I have a Victron Multiplus, and the AC in has three terminals, line neutral and ground.

Originally Posted by kazetsukai

AC - Ground exists for the purpose of tripping safety equipment/GFIs. Its probably a good idea to run ground to the chassis, or to any metallic surface you don't want AC current running through. You need something downstream of the ground to trip for it to be useful. In your kitchen, that's the GFI outlet on the wall.


DC- Negative to chassis is common for both the bus batteries and "house" bank. This is what I like to do:
Attachment 42174

All DC appliances run two wire to the DC fuse panel, and the DC fuse panel(s) connect negative to chassis. There's more to that picture- DC breakers, etc, but that's another discussion.

I'm not an electrician, I'm just some dude that built something that works. Keep in mind, that can happen by accident.

it sounds like both AC and DC should be grounded to the frame? DC sounds easier to accomplish, I'd just have a wire going from one of my terminal bus bars into my chassis. AC I'm not 100% sure. On my Victron MultiPlus, my AC out terminals contain a ground, does that get wired into the chassis or elsewhere?

Thanks for the help, I do really appreciate it!

[kazetsukai]

Originally Posted by chiggins

I looked into one of those, but then I saw this YouTube video, figured I'd go this route:

I'd just need to have a box and circuit breaker down line, I'm just not super entirely sure what I'd need, ya know? Definitely just DIY.

This is fine, but I would not use the PVC elbow- I'd use waterproof entry points for each cable:
https://www.amazon.com/Lantee-Plasti.../dp/B07B9VZYFJ

Originally Posted by chiggins

I'm not entirely sure I follow the wiring for the ground wire. Is it just screwed into the box using a ring connector? Is that the end of the ground there? Or another wire that's screwed in to the box, then screwed into the chassis? Or screwed into the box, and then from there into my inverter?

Screw into box, then go to inverter. The goal is to have the ground wire touch the metal of the box, and then pass it on to the main panel. This is an additional safety measure for ground fault equipment upstream in the shore source in case something in the box goes wrong.

Originally Posted by chiggins

I have a Victron Multiplus, and the AC in has three terminals, line neutral and ground.

Do you know what split phase power is? Sounds like your Multiplus takes 120V AC input. This box is for 240V AC- each "leg" is 120V, 90 degrees out of phase with one another. So when you combine either with neutral, you get 120V AC. When you combine each leg together, you get 240V AC. The breaker in the box pictured is a "double pole" breaker, designed to take both legs.

(Meters attached to each leg in my rig. Combined they show overall power consumption/distribution).



I don't know what your main AC panel looks like. Most residential panels are split phase. I learned this very early on in my research- thus I have a split phase inverter, so that I can use a normal, residential panel:


The double-width or "double pole" breakers are for 240V appliances (in my case, my mini split, my dryer plug). The single pole breakers are for 120V appliances, or your standard three prong outlets. My split phase inverter has three outputs- Leg1, Neutral, Leg2:


Well, your Victron Multiplus outputs 120V AC. It doesn't have a second "leg" for 240V service. So you can't wire a split phase, residential load center (breaker panel) with it the same way you do shore power- half of the positions on the load center correspond to Leg1, the other Half to Leg2. Also, the box you show, only one of those hot legs can actually go to the inverter, as from what you describe, it seems it only takes 120V AC.

I need to see what your main breaker panel looks like inside to go any further here.

Originally Posted by chiggins

it sounds like both AC and DC should be grounded to the frame? DC sounds easier to accomplish, I'd just have a wire going from one of my terminal bus bars into my chassis.

Yeah, nice clean, big cable from negative bus to chassis. And like I said, I did two-wire to the DC appliances.

Originally Posted by chiggins

On my Victron MultiPlus, my AC out terminals contain a ground, does that get wired into the chassis or elsewhere?

Sure, there's certainly no harm in it. Again, the ground is for safety equipment- if you have GFI outlets, and they sense their loads touching the chassis- do you want them to trip? If yes, ground the chassis. This applies to more than your chassis, by the way- what about your kitchen sink/faucet? This is why you see residential appliances (dryers, washers, fridges) internally run their ground connection to the chassis/body of the appliance- so a GFI upstream (if there is one) will trip if the surface of the appliance is electrified.