Direction of DC breaker between battery and inverter

Cuteajax

New Member
I want to install a DC breaker (200 Amps) between my 450Amphr 24 volts battery bank and my 3000W inverter. The type of breaker I have available is the MCB type. I don't know which of the terminals of the breaker should be for the battery and which should be for the inverter. Should the upper (input) part of the breaker be connected to the battery and the lower to inverter or vice versa?
 

Sky-HHI

On Hilton Head Island in South Carolina
You need a DC circuit breaker , is the MCB type for DC or AC ? Most DC breakers have a diagram on them showing the correct way to connect the positive and negative wires
 

Cuteajax

New Member
You need a DC circuit breaker , is the MCB type for DC or AC ? Most DC breakers have a diagram on them showing the correct way to connect the positive and negative wires
My question is which device (between inverter and battery bank) should connect to positive and which to negative?
 

HRTKD

Boondocker
Usually, power in goes to + and power out goes to -. The polarized circuit breakers that I have use ++ and --. I don't know if that is standard or not.

If the circuit breaker is polarized and you have an inverter/charger, then you should NOT be using that breaker.

Always post the exact model and specs of the devices in question, or links to them. Links are always good. I'm not chasing down your equipment all over the Internet.
 

jwelter99

Solar Addict
Most DC breakers have a "line" and "load" terminal. Make sure to hook up properly or they might not function as anticipated. You can just make it out next to each terminal lug below.


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richard cabesa

Solar Enthusiast
I don't know the answer for sure, but I'm here to learn.

When the inverter is plugged into shore power it is acting like a charger and the 70?Amps are heading to the battery.

When the inverter is inverting, the 200?amps are heading from battery to the inverter.

In my mind that would make the inverter the load side.

Someone feel free to correct/educate me

To edit: you didn't say you had an inverter/charger so I could really be off base
 

guitarman59

New Member
I am just starting out too. But I wired my DC Panel with a 250amp DC breaker. The wire from my battery is connected to the bottom lug (line) of the breaker when it's in the off position (down). The top side of the breaker is up in the switch position and this closes the contacts and supplies power on the load side to the inverter. A picture would certainly help.
 

Steve_S

Offgrid Cabineer, N.E. Ontario, Canada
I used the Breakers supplied from MidniteSolar, which are made by Carling Technologies. The 125A & UP breakers which I have used all had clear Load & Line indicators on them.
Link with specs & details:

NOTE, these are NOT cheap.
Fuses & Breakers should always be high quality components as THAT is what keeps you alive and your gear intact should anything go awry.
BussMan, Eaton, Carling all make the Good Stuff and companies like BlueSea ONLY use High Quality reliable components... Never accept cheap knock offs, even when they look identical.

Link to BlueSea Breakers/Fuses:

Hope it helps, Good Luck
 
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