How to know what way power has to flow for solar breaker?

[MrPsychedelic]

I know most situations call for the top to be the feed from your panels and the bottom of the breaker to the charge controller, but how do you know when you do the opposite?

Like for my midnite solar breaker, their diagram showed feed from the panels to the bottom and from the top of breaker to the charge controller. So I just followed that.

But I'm installing a different breaker in a friends system and want to make sure I'm doing it the correct way.

Solar Isolator Breaker (Single Array)

The solar isolator breaker is installed between the solar array and the charge controller to disconnect the pos(+) and neg(-) conductors simultaneously

shop.explorist.life

This is the breaker I'm installing, not sure how to tell which way the power is supposed to feed, or if it even matters.

 

[Q-Dog]

A polarized breaker will should have + and - marked on it.

 

[Brucey]

I know most situations call for the top to be the feed from your panels and the bottom of the breaker to the charge controller, but how do you know when you do the opposite?

Like for my midnite solar breaker, their diagram showed feed from the panels to the bottom and from the top of breaker to the charge controller. So I just followed that.

But I'm installing a different breaker in a friends system and want to make sure I'm doing it the correct way.

Solar Isolator Breaker (Single Array)

The solar isolator breaker is installed between the solar array and the charge controller to disconnect the pos(+) and neg(-) conductors simultaneously

shop.explorist.life

This is the breaker I'm installing, not sure how to tell which way the power is supposed to feed, or if it even matters.

I would contact explorist and ask if this is a polarized or non polarized breaker. If it's polarized and connected in "reverse" you could end up with a fire if it opens under load. Looks like some random Chinese garbage?

Might be this one, which they specify is non polarized.

2025 Others - Yueqing Xianglang Electric Co., Ltd. - Page 1

China Others, XL7-63 6ka Ce Certified C Type 50/60Hz AC DIN Rail Stalled Mini Circuit Breaker MCB,4.5ka CE Certified C Type 50/60Hz AC 220V DIN Rail Stalled Mini Miniature Circuit Breaker MCB by China manufacturer – Yueqing Xianglang Electric Co., Ltd.

m.made-in-china.com

 

[SolarReaper]

I'm looking at the pictogram on the side of those breakers and can't figure why the circuit would be configured like this? The outputs looped back through the breaker just gives a second break in one side of the circuit feeding the load, the other side would have no break and still be connected to the load?

 

[SolarReaper]

The 4 pole version has these options

 

[MrPsychedelic]

I would contact explorist and ask if this is a polarized or non polarized breaker. If it's polarized and connected in "reverse" you could end up with a fire if it opens under load. Looks like some random Chinese garbage?

Might be this one, which they specify is non polarized.

2025 Others - Yueqing Xianglang Electric Co., Ltd. - Page 1

China Others, XL7-63 6ka Ce Certified C Type 50/60Hz AC DIN Rail Stalled Mini Circuit Breaker MCB,4.5ka CE Certified C Type 50/60Hz AC 220V DIN Rail Stalled Mini Miniature Circuit Breaker MCB by China manufacturer – Yueqing Xianglang Electric Co., Ltd.

m.made-in-china.com

I'll contact them and see if it's polarized. I'd hope it's not just Chinese garbage they're extremely highly regarded in the campervan building community for the electrical part.

If it is Chinese garbage would a blue sea on and off that you'd use for a battery work instead for just being able to turn it off on days it'll be below freezing when I don't want the lithium batteries to take a charge?

 

[MrPsychedelic]

A polarized breaker will should have + and - marked on it.

I'm thinking it's not polarized but I'll contact them to be safe

 

[MrPsychedelic]

I'm looking at the pictogram on the side of those breakers and can't figure why the circuit would be configured like this? The outputs looped back through the breaker just gives a second break in one side of the circuit feeding the load, the other side would have no break and still be connected to the load?

View attachment 278593

I'm terrible with what electrical pictures mean and I don't want to give the wrong answer. It does look like both sides connect at 2 and 4 but that'd be an instant short so I'm really not sure

 

[Q-Dog]

This is what a clearly marked polarized breaker looks like.

 

[MrPsychedelic]

This is what a clearly marked polarized breaker looks like.

View attachment 278643

So midnite solar must be polarized then also since it has the same markings. I always wondered tho why the + doesn't follow it straight through or the -. I assume it depends on which way you have the main lead from the panels coming through?

 

[Q-Dog]

So midnite solar must be polarized then also since it has the same markings. I always wondered tho why the + doesn't follow it straight through or the -. I assume it depends on which way you have the main lead from the panels coming through?

I believe they make both polarized and non-polarized. Different applications require different components.

 

[Drunkin Solar]

This is what a clearly marked polarized breaker looks like.

View attachment 278643

Q-Dog where did you get those breakers from? They look nice.

 

[MrPsychedelic]

I believe they make both polarized and non-polarized. Different applications require different components.

Makes complete sense. So as long as I followed the diagram for mine I'm fine right? It's been running for like 4 or 5 months but anxiety's a bitch lol

 

[Brucey]

So midnite solar must be polarized then also since it has the same markings. I always wondered tho why the + doesn't follow it straight through or the -. I assume it depends on which way you have the main lead from the panels coming through?

Yes, the non polarized breakers models end in 1NP. The vast majority of the mnepv line of breakers are polarised so it's critical the panel positive is connected to the ++ end. Eventually the NPs will replace the polarized but will take a while.

If you need non polarized there's the mnedc line but they are don't have 600V rating availability like the mnepvs

 

[Q-Dog]

Q-Dog where did you get those breakers from? They look nice.

Probably ebay, but larger electrical supply places should be able to get them. They are heavy and so smooth compared to the china stuff I have dealt with.

 

[MrPsychedelic]

Do you guys think the explorist life one I'm going to install for my friend will be good? Concerned it's the cheap Chinese garbage now.

It's only a 18V 20A system. (3) 100 watt panels, but still want things safe. They really are extremely highly regarded in the electrical components of campervan builds so that would suck if they're selling crap to use.

 

[Mattb4]

So midnite solar must be polarized then also since it has the same markings. I always wondered tho why the + doesn't follow it straight through or the -. I assume it depends on which way you have the main lead from the panels coming through?

You may understand this but it needs to be crystal clear. The + and the - are source and load dependent. If you wire a source (line) to the top of the breaker you follow through with the same polarity at the bottom (load). The opposite applies if you make the bottom the source (line) and the top the load.

 

[Q-Dog]

Do you guys think the explorist life one I'm going to install for my friend will be good? Concerned it's the cheap Chinese garbage now.

It's only a 18V 20A system. (3) 100 watt panels, but still want things safe. They really are extremely highly regarded in the electrical components of campervan builds so that would suck if they're selling crap to use.

I assume you are only using it as a disconnect? Probably fine. I wouldn't make a habit of disconnecting it under load.

 

[Brucey]

You may understand this but it needs to be crystal clear. The + and the - are source and load dependent. If you wire a source (line) to the top of the breaker you follow through with the same polarity at the bottom (load). The opposite applies if you make the bottom the source (line) and the top the load.

For the midnite mnepv600, for option 2 remove the bridge jumper that ships with it.