I'm curious if there is a process to startup an ESS system when the grid is unavailable (essentially in backup power mode)
For example, let me illustrate a system I have in mind:
An 8kVA Quattro inverter with the grid on AC2 and a small (~5kW) generator on AC1 to provide backup power in case of a serious outage
Some solar panels connected to a Victron charge controller
A CAN bus controlled battery like a Pylontech
A Cerbo GX to control the whole setup
The components are connected to a common DC busbar with isolators on each component so they can be disconnected individually
So here's my hypothetical situation; some disaster occurred whereby the grid is unavailable for an extended period. An issue occurred with the ESS system requiring it to be shut down
Now I'm trying to restart the ESS system without the grid, what order to I start the various parts of the system up?
My guess is that it's something like the following:
- Disconnect all loads on the AC output of the Quattro
- Disconnect the grid input of the Quattro
- Power on the battery and close battery isolator, check battery SoC
- Power on the Cerbo GX and allow to boot up
- Connect charge controller to solar panels and DC bus, switch on and allow to start up
- If the battery SoC is too low to allow the Quattro to safely start, then charge the battery from solar or using the generator and an external battery charger (would need to temporarily disconnect generator from the Quattro to do this)
- Once the battery SoC is high enough, connect the DC input of the Quattro and switch on, allow to start up
- Slowly reconnect the AC loads to the Quattro, allowing for any high startup current to pass before moving onto the next device
- When the grid is restored, reconnect the grid input to the Quattro
Anything I missed or got wrong?
I realise it's a hopefully rare scenario, but I think it's possibly the worst state one could reasonably recover from and it's good to have a procedure just in case