My lead acids batteries have died (sulphur + overheating) and I need to disconnect them. I have a color controller and an MPPT feeding the batteries and to the grid. Do I have to shut down the PVs , MPPT or do I do it via the color controller.
asked
How to disconnect batteries
All that expensive advance tech equipment and no battery switch.
1. Shut down all power source such as PV (turn off breaker or use the charger on/off function of the MPPT software through the CCGX) and grid power.
2. Shut down all connected loads (breakers, fuses, etc).
3. No charging, no loads means no draw on the battery. Safe to disconnect battery from the system. Starts with the negative lead and tape the lug with electrical tape after disconnecting. Do the same for the positive.
4. Before reconnecting, add a properly rated battery switch such as a Blue Sea E-series 9003e (350A continous 48v max). With the battery switch off, you can safely connect the leads back to the battery.
5. Once leads are connected, turn on the charging sources.
6. Turn on the battery switch.
7. Turn on the loads (if loads do not have a disconnect, put the fuses/connections back on first before charging sources or battery switch to avoid connecting under power and sparking).
Disconnect the panels first. Hopefully you have isolator switches between the panels and the MPPT. If not, completely cover the panels before disconnecting.
Then do the batteries.
Make sure the panels are covered before reconnecting, unless you have an isolator.
@BenO
If you have smart mppts you can shut them off in software.
I have the same issue and I need more details: what is the right order to disconnect 2 batteries connected in series?
Should I turn off the entire installation? Will the inverter work immediately after I reconnect the batteries again, or do I need to do some extra steps?
I plan to do this at night, when the panels are not irradiated by sun. I need to change the batteries position and I prefer to do it with the cables disconnected, but I don't know the right order for disconnecting and reconnecting them.
Thank you
I bought a battery switch and followed your advice and now everything is nice and clean design. Big thank you!
