I’m new to the group, I have a multiplus 3000 watt inverter charger in my RV. I’m wondering if I need to have it programmed to properly charge my led acid batteries? I have it set up but I’m not sure if it’s right!
asked
Using a multiplus 3000 to charge led acid batteries
Welcome.
Your installer should have programmed the Multi for your specific use. Check with them to see what programming was done and maybe have them come out to check.
If you did a self-install, you should check all the settings even if the defaults shown in the manual work for your system. You need VictronConnect software, a MK3-USB cable, and a Mac or Windows computer to check settings.
(The manual describes a mechanism to program some but not all settings via the Multi's internal DIP switches. I don't recommend it since there's no way to check your work, but if you are careful it will work OK.)
The VE.Bus Smart dongle only allows operational monitoring and control - no setup. But it's really handy for day-to-day control if you don't have a CCGX or Cerbo GX for control and monitoring or at least the Digital Multi Control panel.
The charger defaults are for Victron Gel batteries. These numbers look close for a generic flooded lead-acid battery. But again, try to get specs for your specific battery (at least type: flooded, AGM, sealed, gel).
Charging voltages are a function of temperature so make sure you've connected the supplied temperature sensor to your battery.
Great, I’m picking up a mk3-usb this morning and I’m going to hook it up. I will check with the manufacturer of the batteries on specifics. The batteries I have are 8, 6 volt wired in Series/parallelto achieve 12 volts. They are flooded batteries. I have had them plugged into the inverter for 2 days and there completely dead..... it seems the multiplus switches from bulk charge to absorption in about 10 seconds. Is that normal!? I suppose I can hopefully change that with the computer setup! Thanks for the reply.
There's something wrong somewhere. Your batteries should have a decent charge on them after 2 days connected to the inverter if it is in ON or CHARGE ONLY and you have AC power feeding the Multi. If you left it on with no AC input and there's a substantial load on the inverter, might have drained the batteries. (You'd need a load of about 200 watts to completely drain your battery bank in 2 days.)
Switching from bulk to absorption in 10 seconds is also not normal either.
If the batteries are completely discharged, you may need to put at least a partial charge on each one individually, then reconnect them into an array. It's probably a good idea to fully charge each one and test it. Most auto supply stores and repair shops can test 12 volt batteries. Not sure if their testers will do 6 volt batteries though.
