Frequently Asked Question
PARM is rock-bottom Battery voltage to shut off the Inverter. If the surge load immediately hits this then either the surge is too great OR the battery wires are too small OR the battery is too small OR the battery is BAD.
PARM can be moved lower BUT not less than PARM. This is surge low voltage cut-off AFTER a DELAY.
PARM sets the surge delay.
These are over-ruled by PARM so if the timer is still active and PARM is hit, Inverter goes off.
Usually because of one of the above issues...