Author Topic: Adding 2nd inverter breaker in MNDC  (Read 123 times)

steff

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Adding 2nd inverter breaker in MNDC
« on: March 29, 2021, 05:26:28 PM »
hello,

Assuming I have 2 inverters and want to fit disconnect for both of them in a standard MNDC-250L  Left handed  ( not a X2, not a Plus model). Would it be acceptable  to dremel the MNDC-250  main breaker opening to fit a second main inverter breaker in the chassis ? It looks doable physically . Should I worry about arcing safety.  I might have to add plastic between the two .  12V battery bank, 2 different PV circuits , one with Midnite Classic 250CP and another Chinese hybrid controller with wind .

ClassicCrazy

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Re: Adding 2nd inverter breaker in MNDC
« Reply #1 on: March 29, 2021, 09:34:19 PM »
At 12v you won't have to worry about arcing. But will you be able to fit  all the big wires in there even if you get the breaker to fit ? That is probably the question.

Larry
system one
Classic 150 , 5s4p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system two
Classic 150 ,5s 135 watt Kyocero , 16s Calb 100AH LiFePO4 , Outback VFX 3648 inverter
system three
Midnite KID MPPT 24 DC in to  12 volt AGM batterie

steff

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Re: Adding 2nd inverter breaker in MNDC
« Reply #2 on: March 30, 2021, 02:09:53 PM »
Thank you Larry.
so even if my classic is roking at higher voltage from PV side, since it's outputing 12V to battery ther would be no arcing because that side is all 12V. Another wuestion if I do it this way how many GFP's do I need ? Is it one per charge Controller ?

thanks

ClassicCrazy

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Re: Adding 2nd inverter breaker in MNDC
« Reply #3 on: March 30, 2021, 06:01:51 PM »
 I don't know your setup. In my MNDC box the big inverter breaker sits up at top . The other breakers are below it.
What is your PV input voltage ?  If you look at a typical 240v  high voltage breaker box in a house the breakers are all next to each other .
I don't know the answer to your ground fault protection question. Some models of the Classic have them built in - not sure which Classics you have.

Larry
system one
Classic 150 , 5s4p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system two
Classic 150 ,5s 135 watt Kyocero , 16s Calb 100AH LiFePO4 , Outback VFX 3648 inverter
system three
Midnite KID MPPT 24 DC in to  12 volt AGM batterie

steff

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Re: Adding 2nd inverter breaker in MNDC
« Reply #4 on: April 01, 2021, 12:59:12 PM »
hi have a Midnite classic 250-CP ( overstock from DC solar production ) but bought directly from Midnite so full service warranty applies. It Think it does not have wind or Follow me butthat's ok my setup is modest . Its an offgrid cabin and am wiring for 12V no AC for now except plugging directly to inverters (2 of them). Since my classic does not do wind, I have a cheap chinese MPPT-Wind/ PWM Solar controller for a windmill and ancillary panels.

 Thinking of 24V  from 2S4P x 100W panels (800W) to the Midnite Classic charge controller then 12V to battery stacks. Same thing on the  Chinese ancillary  PV  and Wind mill so I can squeeze more power out of it, 24V incoming then 12V to batteries and inverters . 

Eventually I will wire AC and an AC box to my largest inverter.