The older PowerMax models were like WFCO in that your batteries had to be low, around 50% or less, before the converter would start in boost.
Later models like the PM4s now have a feature more like Iota's. The newer PMs always start in boost and run for 15 minutes at that, then they will stay in boost or drop to 13.6 depending on the state of the battery ( ISTR if the battery voltage is still under 14.3 when the 15 min is up.) If they stay in boost they will then drop to 13.6 once battery voltage reaches 14.6 as usual.
In the above case, the batteries were already quite high in SOC, so the 15 minutes was all it did. Working as designed. Even showed how it eventually goes to 13.2. Very good test.
