shunts

I am installing a ground fault into my off grid system. My shunt is not tapped to add a negative buss bar to it. Can I use the bolt that attaches the negative from the battery to also secure a buss bar to attach all my negatives to or do I have to buy a new shunt with the buss bar?

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,433 admin
    Re: shunts

    Two things...
    1. You need to have a thread or two above the nut/lock washer when all of the lugs are tied to the shunt "buss point".
    2. Make sure there is no undo loads/stresses from the heavy/inflexible cables that would try to pull the shunt apart.
    If you cannot do 1&2--Then you should have a separate bus for all of your negative/return connections.

    Also, in the end, it may be easier with a separate bus bar to return different sized cables (14, 8, 0, etc.) cables back the battery bus point vs trying to put ring lugs for 1/4" post (or whatever size the shunt posts are) for the wide variety of wire sizes. (many bus bars have captive screws and do not require any cable termination/crimping).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Kamala
    Kamala Solar Expert Posts: 452 ✭✭
    Re: shunts

    Here is a photo of my shunt/negative buss bar.
  • audredger
    audredger Solar Expert Posts: 272 ✭✭
    Re: shunts

    Kamala, the "sawdust" part confuses me ..... who was the suppler and was it expensive???
  • Kamala
    Kamala Solar Expert Posts: 452 ✭✭
    Re: shunts

    :roll:

    Sawdust was removed last November when the camper was stored.

    But... I (the vendor) will be providing ample quantities in a few more weeks.

    :D

    The bigger picture.
  • n3qik
    n3qik Solar Expert Posts: 741 ✭✭
    Re: shunts

    OT: I see one very big problem. The batteries are not tied down.
  • Kamala
    Kamala Solar Expert Posts: 452 ✭✭
    Re: shunts
    n3qik wrote: »
    ... The batteries are not tied down.

    That will be taken care of. Trailer is parked permanently for the time being.