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DC Circuit breaker wiring

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Robert_Off Grid

Electrical
Sep 25, 2020
1
Hi all 1st time poster. looking for some advice with regards to wiring options for DC moulded case circuit breakers
Assuming both poles of double pole DC circuit breaker are correctly rated for application and only single pole protection/isolation is required Is it Ok to wire 2 x positive polarity conductors ( 2 x circuits) through the same double pole MCCB ( normally this MCCB would have both +/- connected through it)

The loads would be Inverter Chargers

Thanks
Rob
 
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What does the breaker listing say? That’s all that matters. What anybody here says is irrelevant if it conflicts with the listing requirements.
 
Wire the poles in series.
That will give you added overvoltage capability in the event that the input voltage rises for any reason.
If the breaker is between solar panels and the charge controller you may have higher open circuit voltages.
Bill
--------------------
"Why not the best?"
Jimmy Carter
 
What Bill says is probably required. May not be sufficient.
 
What DavidBeach says.
DC's a batch

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
Is it acceptable to trip an unfaulted circuit for a problem on the adjacent one? Or to open both circuits for maintenance on one? Series sounds like a good way to go.
 
If the breaker has a DC rating it is acceptable, sometimes necessary, to wire all of the breaker poles into the circuit being protected, see the figures on page 6 and 7 of the attached. "DC Rated Thermal-Magnetic Molded Case Circuit Breakers Class 601".
You need to read the application bulletin for your specific breaker, when protecting DC circuits, DC parameters of breakers are rarely the same as when applying the same breaker on AC.
Fred
 
 https://files.engineering.com/getfile.aspx?folder=e4f375bc-276d-4868-8f0b-54cc378093a4&file=0601DB0401.pdf
Are you asking if you can run two separate circuits (one per pole) through the one breaker?
If you are it's not something I'd recommend, if nothing else you'll end up with isolation issues and confusion.

EDMS Australia
 
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