A system with a Victron MultiPlus-I at 24 volts, OPzS batteries with 675 Ah (12 batteries total), and a SmartSolar 150|100 charge controller. The SmartSolar is in slave mode. VEConfigure has a maximum battery charge current of 80A, the SmartSolar is configured to 100A, and DVCC is set to 80A. The system is using the ESS Assistant. The problem is as follows (it’s a new installation): when loads are applied that require more power than the SmartSolar is providing, the SmartSolar shuts down, and the system runs only from the batteries, instead of taking the maximum available from the MPPT and the rest from the batteries. What could be happening? I think the battery voltage might drop too much when the load is applied, before the MPPT can respond, and some parameter is causing it to shut down. After a while, it tries to restart in cycles but doesn’t succeed as long as the heavy load is present.
I performed a test. The batteries were fully charged, so the voltage was 28.8V. Very little solar was coming in, about 300W, because the charger was restricting output since the batteries were full. I applied a load of 2500W, and the SmartSolar responded, working correctly. In fact, at one point it showed 2600W, even though it’s only supposed to provide 2400W. At that moment, I increased the consumption to 3900W, and the battery voltage dropped to 23.5V while the SmartSolar was still providing its full output, before it shut down again. I checked VEConfigure, and it seems the ESS Assistant has a discharge limit parameter (0005c) which is the voltage limit. Later, I lowered it to 22.5V, but the same thing keeps happening, even with loads of 2500W. It’s as if the SmartSolar tries to supply all the necessary power without sharing the load with the batteries, and this causes it to shut down.