PM864A(With Battery Backup) Program erased during Power Shutdown
PM864A controller running with SB822 external battery backup. During Power shutdown and Power turned on, Program erased in controller and have to download once again.
Battery get replaced and the same issue is repeating during shutdown. Battery Input and Output Voltages are tested and found ok. Cable from Battery to Controller also tested its continuity and tightness and that's also ok. Any suggestion?????
Check internal battery, should be disconnected when using SB822.
Second (a long-shot):
Are you sure that it is a battery problem? ABB network loop/storm protection could possibly make the PM discard program (if this occurs at the same time with shutdown, due to errors in switch configuration,) This might happen depending on your PM's firmware version.
Confirm NO internal battery in both controllers while using SB822 external battery as parallel connection to 5V not allowed and also ensure "B" should be lit constant if battery is Ok.
always its better idea to connect battery after commissioning to avoid battery life cycle due to block outs.