Multiplus high DC voltage shut down with Pylontech home storage

I’ve read a few questions around this but in different situations.

I have a muliplus ii 5000 with Pylontech us5000/ us3000 batteries. System has all house loads on the AC out and just the EV charger outside of the Victron environment. All solar is AC connected
+Cerbo GX using ESS

When adding additional batteries to the stack I’ve noticed as the batteries are shut down the Multiplus gives a high DC alarm and shuts down . This is when all batteries are turned off and isolated . Saw similar when unplugging the pylontech Comms cables too.

Problem repeats whenever batteries turned off for maintenance like moving cabinets etc .

Why does this happen as I lose power to the house ?After 2 mins it fires up again without the batteries but won’t transfer to running just on grid when batteries are disconnected .

GX is powered from the battery connection point on the Multiplus which is my only thought as the GX presumably loses power

Hopefully someone can help improve the system so it doesn’t power off every time I fiddle with batteries

Why are the batteries shutting down?
That’s the real problem.

Everything configured correctly?
https://www.victronenergy.com/live/battery_compatibility:pylontech_phantom

I hope this is a troll post.

If you left the inverters on and turned off the battery then that is the issue. It is a battery based system and not designed to work without it. (Many features in an ESS programmed system such as power assist require the battery to be connected switched on and capable)

The system should be fully shut down and tested safe (bypassed if power is critical). For both your safety and for the equipment longevity.
Battery loss of communication is technically a fault condition as well during normal operation as it requires the BMS through DVCC (note forced on by the battery) to control the system.

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Maintenance, relocating in racking etc

Appreciate the reply even with the condescending tone. I did say it was isolated but it seems my expectation it would continue to work using AC power is clearly not right. Thank you