Looking for another way to Aux1 PWM water heater elements

[SolarMusher]

Hi all,
After 10 days playing with Aux1 wastenot trying to tweak it to work correctly in different weather situations, I'd like to try to control the PWM load ouput of a cheap diversion controller (tristar) from the Classic Aux1 wastenot. The last time I've experimented this way, the Classic started an arc fault alarm as soon as I switched the load breaker on, I switched off immediately as I didn't know where this fault really came from and didn't want to damage anything. This 20A load was taken directly on the same positive battery busbar which is used for Classic batt output and not directly on battery posts, so today I'm pretty sure that this alarm came from this sudden load drawing and has been read as an arc fault by the classic, maybe AF sensivity which was set too high. So, I'd have a few questions:
Is the aux1 wastenot signal On/Off only? I mean a steady 12V signal.
Could this signal be used to control a PWM load output (from a second CC)?
Should I lower Arc fault sensitivity a little bit?
Thanks for any help,
Erik

[mike90045]

What about controlling an inverter Enable signal, and the inverter (could even be a mod sine) powers a load ?