Why is my battery on stand by?

Please be advised that under below 2 situations, inverter will enter into standby mode:
During the discharging period, if it meets below conditions at the same time:
a. there is no pv
b. load power is very low(less than 100W), lasts for 5min
During the charging period, if it meets below conditions at the same time:
a. battery SOC> SOC of "charging from grid"
b.there is no PV