Magnum me-BMK and generator

fred_dou
fred_dou Registered Users, Users Awaiting Email Confirmation Posts: 3
( sorry, my english is very bad, I'm french canadian and use google translate......... :( )

Hello
  I have an inverter magnum MS-4024 pae, I connect a generator 240 volts. A battery bank, solar panels and a charge controller. Everything works fine. To ease the drive of the level of my battery, I added a module ME-BMK of magnum and there I have a problem. I checked all the connections, look at the plans, the video of youtube and the programming and I do not know what to do anymore.

  When my battery bank is recharging by the sun, no problem the ME-BMK tells me the % charge (SOC) and increases with the charge that the sun gives to my batteries. When I use electricity, again there is no problem, the BMK SOC% decreases. On the other hand if I connect the generator 240 volts, it recharges well battery bank with the charger integrate to the inverter ms-4024, but my SOC% it decreases, as if I emptied my batteries, when in fact they are going to recharge. I checked and she really recharges.

  As the generator is connected directly into the inverter and the batteries are really charging, I do not see what connection I could have reversed? I tell myself that there may be a trick in programming that I could not find?

Tanks for you help and patient :)

Comments

  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    edited March 2018 #2
    A few thoughts/questions:

    Where is the shunt installed? The battery side of the shunt should have only the battery negative connected. All charging sources and loads should be on the load side of the shunt.

    Is the generator grounded? If so, how?

    Is the battery negative grounded? If so, how?

    Is the AC panel grounded?

    Is there a neutral to ground bond? If so, where?

    Were there any significant loads running while on generator power?

    How do you know batteries are really charging with generator (DC clamp ammeter, battery voltage, or ?)
    Off-grid.  
    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
  • fred_dou
    fred_dou Registered Users, Users Awaiting Email Confirmation Posts: 3
    edited March 2018 #3
    Tanks for your help :)

    Where is the shunt installed? The battery side of the shunt should have only the battery negative connected. All charging sources and loads should be on the load side of the shunt. One side the shunt with battery négative.  All charging sources and load other side of the shunt. 

    Is the generator grounded? If so, how?  ac ground generator connect directly to the ground ac in the inverter.  The Ac inverter ground connect directly to ground the AC panel.

    Is the battery negative grounded? If so, how? not grounded

    Is the AC panel grounded? Connect to inverter ac ground, but not connected to a rod to earth.

    Is there a neutral to ground bond? If so, where?  yes in the panel the neutral and the ground are connected by a jumper provided for this purpose of serie

    Were there any significant loads running while on generator power? nothing, just charge my battery bank

    How do you know batteries are really charging with generator (DC clamp ammeter, battery voltage, or ?) Check with dc clamp ammeter and with battery voltage the ME-ARC remote.
  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    This seems to pretty much rule out the issues I was thinking about. Perhaps someone with more experience with the display will chime in.

    One further thought occurs to me though. I'm wondering if only the charge controller current and DC loads (if any) are measured by the shunt, and inverting/charging currents are measured internally in the inverter for the display. If so, it may be normal for the inverter to provide a positive number for inverting, and a negative one for charging.
    Off-grid.  
    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
  • fred_dou
    fred_dou Registered Users, Users Awaiting Email Confirmation Posts: 3
    checking done and editing my answer
  • SolarMusher
    SolarMusher Solar Expert Posts: 176 ✭✭✭
    Salut Fred,
    Appele moi, si tu n'es pas trop loin. Je suis dans les Laurentides.
    (819) 717-3652
    A+
    Erik
    www.solairelaurentides.com