Charging battery’s I figured I could charg

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Comments

  • wellbuilt
    wellbuilt Solar Expert Posts: 763 ✭✭✭✭
    Whoops 2/0 g cable 
    Out back  flex power one  with out back 3648 inverter fm80 charge controler  flex net  mate 16 gc215 battery’s 4425 Watts solar .
  • littleharbor2
    littleharbor2 Solar Expert Posts: 2,036 ✭✭✭✭✭
    A 175 amp fuse or breaker is a common size in mid sized 48 volt inverters. 250's are common on 24 volt inverters. I see you have 8 battery strings so without rereading the whole thread, just deducting you system is 48 volts.
     Hope I'm not completely out in left field with this comment.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric,  460 Ah. 24 volt LiFePo4 battery bank. Plenty of Baja Sea of Cortez sunshine.

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    If you have a 48 volt battery bank/bus--A good starting point (of course, use the manual for the "correct" information):
    • 3,600 Watts * 1/0.85 AC inverter eff * 1/42.0 volts battery cutoff = 100.8 amps
    And I highly suggest that you run everything 1.25x (1/0.80) NEC derating for continuous current rating:
    • 100.8 amps * 1.25 NEC derating for continuous current = 126 Amp minimum Breaker/Branch Circuit Rating
    If this is an Inverter-Charger, the actual power requirements may be different...

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Raj174
    Raj174 Solar Expert Posts: 795 ✭✭✭✭
    @wellbuilt
    Your system has a 175 amp inverter breaker, so you'll want a 175 amp fuse on each string of 8 batteries.

    Rick
    4480W PV, MNE175DR-TR, MN Classic 150, Outback Radian GS4048A, Mate3, 51.2V 360AH nominal LiFePO4, Kohler Pro 5.2E genset.
  • wellbuilt
    wellbuilt Solar Expert Posts: 763 ✭✭✭✭
    Thanks for  The information 
    Out back  flex power one  with out back 3648 inverter fm80 charge controler  flex net  mate 16 gc215 battery’s 4425 Watts solar .
  • Daren
    Daren Registered Users Posts: 0
    I've got 4 deep cycle batteries connected to a 1500 watt inverter my battery bank reads 16v on a meter but read 11.2 on my inverter I also have a charge controller hooked to it why is my battery bank reading 11.2 and when I put the meter directly to my bank it reads over 16?
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
     Have you measured the voltage on the inverter DC input?

    To much voltage drop in wiring? Need short and heavy cables from inverter to battery bank. At full power, your inverter could draw over 130 amps.

    Also 11.2 volts at the battery is suspect too. Possibly the battery is under charged, drawing too much current through your inverter for battery bank size (too small of bank), or aging/sulfating battery bank.

    Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset