Hi all. I have come across this installation where there is an inverter which feeds part of a DB. All the labelling is there and it is very apparent which circuits are fed from the inverter.
The inverter is fed from a single pole circuit breaker (normal supply) which in turn is fed via a 4 pole earth leakage. This single pole circuit feeds into the inverter. The output of the inverter is protected by a 4 pole circuit breaker which then distributes the power to certain circuit breakers in the DB. The system apparently works.

However, the neutrals from the circuits are connected to the earth leakage neutral bar. So the circuit should work unless the earth leakage trips in which case the neutral is in effect disconnected. This obviously will cause the loads to stop functioning but the lives will still have a potential of 220V to earth.

Surely the circuits that are connected to the inverter should have a separate neutral bar and as these circuits will feed dedicated socket outlets the earth leakage should not be connected to them but remain for the normal supply protection.

Has anyone any comments while I look through the SANS book?