Been running a similar setup in my motorhome for a couple of years now so picked up a few things the hard way 😅
My sequence that's worked reliably:
Power-up:
- Battery bank first (let the BMS wake up properly — give it 10-15 seconds)
- DC loads / 12V bus
- Inverter on
- Solar/charger inputs last
Power-down:
- Disconnect AC loads first
- Inverter off
- Charger inputs
- Battery isolation last
The big one people miss — never hit the inverter before the BMS has fully initialised. Had a Victron Multiplus briefly throw a fault doing exactly that with my Fogstar Drift 200Ah. Not catastrophic but not ideal either.
Also worth noting: if you've got a pre-charge resistor setup on your system, make sure that's doing its job before closing the main contactor. Skipping it causes those horrible inrush current spikes that'll degrade your connections over time.
Curious what others are doing differently. A few questions for the thread:
- Anyone running a different order for solar input vs inverter on the power-up side?
- Does your BMS automatically handle any of this sequencing or are you doing it manually?
- Any relay/automation setups (Cerbo GX timers etc.) people have found useful?
I've been toying with automating the sequence via a Cerbo but not got round to it yet. Feels like it'd reduce human error massively, especially when you've just arrived on site tired and want everything up quickly without thinking about it.