Thanks to Rohan Wilschefski’s advice I found a second hand Merlin Gerin NS160 N circuit breaker from eBay. I then found a compatible 48V 30w shunt trip. This will allow the Batrium BMS to disconnect the Battery from the inverter in case of emergency such as Low Cell Voltage, High Cell Voltage etc.
Merlin Gerin NS160N
The shunt trip arrived today from the USA – even in the middle of the Corona Virus outbreak, international shipping is still quick!
fitted it into the circuit breaker and tested it. Everything works as it should.