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Circuit Breaker on Solar

Vintage465
Nomad
Nomad
I'm putting in some circuit breakers on my solar upgrade. Question is...on the breaker one side is Battery and one side is Auxiliary. My thought would be that the "input" or solar side would go on the "battery" post side of the breaker and the Auxiliary would then be hooked up to the side that goes to the battery. Now this is backward to the actual, "this is the battery and this is battery post". My thought is the power or higher amount is coming from the solar and it seems to me like that should get the "battery" post on the breaker. What are your thoughts?
V-465
2013 GMC 2500HD Duramax Denali. 2015 CreekSide 20fq w/450 watts solar and 465 amp/hour of batteries. Retired and living the dream!
7 REPLIES 7

pianotuna
Nomad III
Nomad III
What happens if you don't?

https://www.youtube.com/watch?v=Oaq2cvoPBRk

I don't know if all dc breakers are polarized
Regards, Don
My ride is a 28 foot Class C, 256 watts solar, 556 amp-hours of Telcom jars, 3000 watt Magnum hybrid inverter, Sola Basic Autoformer, Microair Easy Start.

CA_Traveler
Explorer III
Explorer III
I don't recall any polarity indication on my 80A DC CB. However the solar controller is the charge source and hence connect it to the battery terminal on your CB.
2009 Holiday Rambler 42' Scepter with ISL 400 Cummins
750 Watts Solar Morningstar MPPT 60 Controller
2014 Grand Cherokee Overland

Bob

time2roll
Nomad
Nomad
I did not realize a DC breaker had polarity. AC breaker does not care.
I use a fuse from controller to battery just to protect the wire.

pianotuna
Nomad III
Nomad III
.
Regards, Don
My ride is a 28 foot Class C, 256 watts solar, 556 amp-hours of Telcom jars, 3000 watt Magnum hybrid inverter, Sola Basic Autoformer, Microair Easy Start.

TechWriter
Explorer
Explorer
Check out this MidNite Solar article on DC breakers.
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Vintage465
Nomad
Nomad
CA Traveler wrote:
Not sure what you are asking. CBs are normally rated for amps. DC however is much more subject to contact arcing than AC. Panel wires typically connect to the solar controller input and the controller output connects to the battery. The controller may require a disconnect on both input and output.

I used a 240V dual switch (typical AC switch for A/Cs) on my solar panel wires which carry 9A at 90V+. I used a 80A DC CB for the battery side.


What I'm asking is this: All Circuit breaker have a "line" or "in" and and a "load" or "out". In any normal use of a circuit breaker the "line" or "in" post would be from the battery. On the circuit breaker the input post says "Battery". The "load" side says "Aux" and that is what goes out to what ever it is that puts load on the breaker. In a solar application....I see the Solar as the "Line" and the battery as the "Load". So I'd be running the solar into the "battery" side of the breaker and then out the Aux side of the breaker to the battery, as I see the battery as putting the load on the circuit.....
V-465
2013 GMC 2500HD Duramax Denali. 2015 CreekSide 20fq w/450 watts solar and 465 amp/hour of batteries. Retired and living the dream!

CA_Traveler
Explorer III
Explorer III
Not sure what you are asking. CBs are normally rated for amps. DC however is much more subject to contact arcing than AC. Panel wires typically connect to the solar controller input and the controller output connects to the battery. The controller may require a disconnect on both input and output.

I used a 240V dual switch (typical AC switch for A/Cs) on my solar panel wires which carry 9A at 90V+. I used a 80A DC CB for the battery side.
2009 Holiday Rambler 42' Scepter with ISL 400 Cummins
750 Watts Solar Morningstar MPPT 60 Controller
2014 Grand Cherokee Overland

Bob