Author Topic: 250A breaker to MNBDM wiring  (Read 642 times)

Trukinbear

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250A breaker to MNBDM wiring
« on: October 23, 2020, 05:57:36 PM »
Hi guys, I've got the MNBDM mounted in my E-panel. Looking at the connection to the 250A main DC breaker, terminals on the MNBDM say + and -, but both of the wires from the breaker are yellow and appear to be connected together at the end(?). Perhaps this just a 'normally closed' situation where polarity doesn't matter but as soon as I snip the wires apart the breaker will trip, right? Or am I just confused?
SMA Solar Sunny Island SI6048
JA Solar 330W 72 cell panels (18)
Classic 250 (2)
MODBUS/Canbus comm adaptor for Sunny Island
SMA-OG E-panel
WhizBang Jr
MNSPD300V (3)
Atkinson GSCM mini-i
Onan Quiet Diesel QD-8000
Monterey 986Ah 'Big Sur' 24-125-11 48V battery
Off the grid on the PNW coast

FNG

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Re: 250A breaker to MNBDM wiring
« Reply #1 on: October 26, 2020, 04:56:57 PM »
The MNEDC175RT and MNDC250RT breakers have the trip coil, This coil is not polarity sensitive so the + or - from the BDM can go to yellow wires and you don't have to worry about polarity

Trukinbear

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Re: 250A breaker to MNBDM wiring
« Reply #2 on: October 26, 2020, 05:50:28 PM »
Thank you!
SMA Solar Sunny Island SI6048
JA Solar 330W 72 cell panels (18)
Classic 250 (2)
MODBUS/Canbus comm adaptor for Sunny Island
SMA-OG E-panel
WhizBang Jr
MNSPD300V (3)
Atkinson GSCM mini-i
Onan Quiet Diesel QD-8000
Monterey 986Ah 'Big Sur' 24-125-11 48V battery
Off the grid on the PNW coast