Wired correctly

SouthAfrica75
SouthAfrica75 Solar Expert Posts: 36
I would like to make sure I have my system wired correctly for what I'm trying to achieve.

Have a 1200 watt inverter with 2 x 12v (105amp) batteries.
If I've wired it correctly it should still be giving me 12v but with 210amps

Inverter positive is going to battery #1
Inverter negative is going to battery #2

Positive from battery #1 and #2 are wired together
Negative from battery #1 and #2 are wired together

Hope this makes sence......

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Wired correctly

    Yep, you have it correct... Just to clarify:
    Inverter positive is going to battery #1 Positive Terminal
    Inverter negative is going to battery #2 Negative Terminal

    The reason for the batt#1 and batt#2 terminal positions is so that each battery sees the "same resistance"... If the load terminals were attached to battery #1 only, and jumpers to battery #2--number one will see the "lowest resistance" and supply more current than battery #2 (because of the extra jumper cables/connections). And, typically, battery #1 will wear out faster...

    Alost, when you say give you "210 amps"--this is really 210 Amp Hours from 100% state of charge to 0% state of charge at a 20 hour rate (or 210AH/20H=10.5 amps for 20 hours--of course, you normally should only use 50% of this--so 10.5 amps for 10 hours).

    And, your battery's apparent capacity is higher at 20 hour and 100 hour rates, and lower at 1 hour and 10 hour rates (the higher the current, the more the internal resistance of the battery and chemical processes waste more energy by turning it into heat--similar issues when charging).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SouthAfrica75
    SouthAfrica75 Solar Expert Posts: 36
    Re: Wired correctly

    Bill

    Thanks for the fast reply..... yeah, I meant to say 210 amp hours with both batteries together
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Wired correctly

    SA,

    Just give me a quick swat if my replies continue to increase in length :p

    Obviously, I am also trying to help other who are new at this to understand why the question was asked.

    -Bill :roll:
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Wired correctly

    Connecting on the "diagonal" will extend the life of the batteries by helping share the loads.
    http://www.smartgauge.co.uk/batt_con.html
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