combiner breakers

ws9876ws9876 Solar Expert Posts: 397 ✭✭✭
If you look at the DC breakers for the MNPV6 box you see how there is a plated copper bussbar with square tabs pointing down....
the breaker slides along the DIN rail and connects to one of those tabs...I guess you can cut the bussbar in 2 pieces and have 2 set ups going at once....but I am wondering how does the DC breaker attach onto the top of the breaker..?? Does it just push on or does it slide on sideways...I am asking because I am building my own combiner/breaker box out of an enclosure I have from an old well pump controller.
I will have 2 breakers for combining and 4 breakers for other breakers/ GFP63 and 2 -30 amp DC breakers. All on 1 din rail that I will bolt in.
I was going to cut my own bussbar out of copper plate but was wondering if I could just use small jumpers from the top of the breakers
to the big combiner lug nut and skip the bussbar??Can I use wire instead of the bussbar..??maybe 8 ga..??


  • PhotowhitPhotowhit Solar Expert Posts: 5,139 ✭✭✭✭
    The comb like thing, just inserts were the wire would and you tighten down on it...

    The spacing is different on either side for fuses or breakers.

    Image result for midnite breaker din combiner
    The only 'trick' to making your own is adding a lug for the combined output.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do
  • ws9876ws9876 Solar Expert Posts: 397 ✭✭✭
    but you dont have to use a copper plate bussbar,correct?? You can just wire it all up..??
  • EstragonEstragon Registered Users Posts: 4,457 ✭✭✭✭✭
    The buss really just makes it easier to make a good, solid, secure parallel connection. Getting a good connection with more than 2-3 large-ish wires can be harder with just the wire, but it can be done.
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • BB.BB. Super Moderators, Administrators Posts: 30,194 admin
    "Bus Bars" are a large class of objects... For example, here are some common ones used in wiring:

    Some people have taken copper water pipe, smash flat, drill holes, and made bus bars out of them.

    Member @2manytoyz has a nice website. About 1/2 way down, he has a set of links/pictures that show the evolution of his backup solar power system. Lots of Do It Yourself information:

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • VicVic Solar Expert Posts: 2,987 ✭✭✭✭

    ws  ..,

    Each of those MidNite MNEPV breakers  has two screws  --  one at the top,  and the other toward the bottom of the breaker.   The busbar fingers slip into the terminal of the breaker at the top,   and  the screw on the terminal secures the breakers mechanically,   and also makes the common connection for the output of the Combiner,   to the CC PV input.

    That Tin-plated busbar  is included with the MNPV6 Combiner.  Often the MN Combiners have  segmented output busbars,  which allow feeding separate PV array to each of two CCs.  For a single CC,  the segment busses are sandwiched together,   and connected and held by the output terminal for the PV cable.

    The busbar stabilizes the row of the breakers.   Without making your own  busbar (if you are making your own Combiner),   then you will need to place two wires into the top of most of the breaker terminals  (not advised) ,   or make your own  busbar.

    Is this something that you really want to do ?

    You can buy the correct busbars at the WInd-Sun store,   and they are not that expensive,   of course,  neither is the whole Combiner (IMO).

    FWIW,   Vic

    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH [email protected], 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
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