On the MS4348PAE I would check the “Threshold Setting” in the ME-RTR. If you set the threshold lower or OFF the Slave will respond faster to help the Master run loads.
To Change the Threshold setting:
1. Push the SETUP button
2. #2 Inverter SETUP
3. 02E Parallel Threshold
The default setting is 60% which means that the Master must exceed 60% capacity or 2580 watts (4300 x .60 = 2580 watts) before the Slave turns ON. If you lower this setting to 30% then the Slave will turn on at 1290 watts (4300 x .30 = 1290 watts). If you set the Parallel Threshold to OFF then the Slave will always be ON, the settings are in 10% increments. This settings is the same for ALL Slave inverters so if there were 1-Master and 3-Slave inverters in a system ALL the Slave inverters would come on at the Parallel Threshold setting. After approximately 2 minutes any Slave would turn OFF if the combined load is less than the Master plus needed Slaves.