question

trevor4321 avatar image
trevor4321 asked

MultiPlus II GX blows 30A breaker

This is a new sysyem for ESS comprising MultiPlus II GX 48/5000/70-50, 3 Pylontech US2000C batteries with an external current transformer on the grid input.

Initially powers up fine, no batteries connected yet.

Clunking, relays?, from the MultiPlus. Display is showing the grid power, obviously batteries are showing low voltage because BMS not connected.

Connect batteries, more clunking, battery voltage now reading OK, about 49.3V. But have lost grid monitoring display says AC Disconnected also error #15 comes up. Says it's in ESS 3,4,5. After a little while longer more clunking and the 30A breaker trips out.

I have limited power on both charge and discharge to 3KW.

I have also tried running it in charger mode with the same result.

Only happens when batteries connected, runs for days if not.

I have been in touch with the supplier 3 weeks ago but they are not being very pro-active.

I am wondering if there is something wrong inside or has anyone else got any suggestions.

Trevor

multplus 2 gx
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

3 Answers
Alexandra avatar image
Alexandra answered ·

@Trevor4321

First of all. The battery is meant to be connected before anything else. It is a battery based system.

See the manual. It is the first thing that is mentioned.

https://www.victronenergy.com/media/pg/MultiPlus-II_230V/en/installation.html


Second. Low battery is because it is not programmed correctly, or the battery is tripping. Not because there are no comms.

Follow the guide.

https://www.victronenergy.com/live/battery_compatibility:pylontech_phantom


Third. Probably blowing/tripping a 30A breaker (i assume you mean AC) because the default input current limit is 50A. Again points to programming. Unless you have a wiring issue? Or because of the inrush for precharging the inverter.


ESS 3, 4 & 5. Are BMS related. And temperature related.

https://www.victronenergy.com/media/pg/Energy_Storage_System/en/controlling-depth-of-discharge.html#UUID-898081fc-12c0-210f-e2d4-db3e3c8c28fb


VE Bus error #15

https://www.victronenergy.com/live/ve.bus:ve.bus_error_codes#error_15_-_vebus_combination_error

You did not update system components, before commisioning or programming?


Also wanted to point out you need one more battery if they are us2000s to meet the minimum requirements of a 5kVa.

https://www.victronenergy.com/live/battery_compatibility:pylontech_phantom#minimum_battery_sizing_recommendations

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Jason - UK avatar image
Jason - UK answered ·

@Trevor4321 do you have a schematic of your system? What do you have connected to the AC out's? Photos of the connections on your unit would be helpful.

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

daza avatar image
daza answered ·

I would connect back to the grid and put a clamp meter on the house to make sure your demand is staying within your 30amp limit. You know that the 48/5000 has a pass through of 50amps is there a reason why you or your installer has gone down 20amps?

5 comments
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Related Resources

Additional resources still need to be added for this topic