Hi all,
This may be an easy one to answer, but might be hard to explain...
I maintain a residential property which relies on three flood water pumps to avoid being flooded when the water table is high. The electrician has fitted an ATS generator. As the building is remote from the main house which is PME, an earth rod has been fitted. The electrician has fitted a 32A 30mA RCBO in the fuse box to supply the ATS unit. The ATS then feeds three 6A RCBOs for the pumps and one 16A RCBO for a socket and light in the generator shed.
The problem I have is that if any one pump has a fault, it is likely to trip the main 32A RCBO which would flood the building. There are voltage and float alarms and such like, but no good if no one is in.
To get to the point, can I change the 32A RCBO which supplies the ATS to an MCB?
The cable is in a 3m length of conduit which doesn't run in any walls and the ATS would be the only device not RCD protected and it immediately feeds the other RCBOs.
Is this allowed with a TT system? If not, which level of RCD protection is the minimum required (eg time lag, higher current?). Ideally we would want no RCD between ATS and CU, but the electrician said this is not possible.
Any advice appreciated
This may be an easy one to answer, but might be hard to explain...
I maintain a residential property which relies on three flood water pumps to avoid being flooded when the water table is high. The electrician has fitted an ATS generator. As the building is remote from the main house which is PME, an earth rod has been fitted. The electrician has fitted a 32A 30mA RCBO in the fuse box to supply the ATS unit. The ATS then feeds three 6A RCBOs for the pumps and one 16A RCBO for a socket and light in the generator shed.
The problem I have is that if any one pump has a fault, it is likely to trip the main 32A RCBO which would flood the building. There are voltage and float alarms and such like, but no good if no one is in.
To get to the point, can I change the 32A RCBO which supplies the ATS to an MCB?
The cable is in a 3m length of conduit which doesn't run in any walls and the ATS would be the only device not RCD protected and it immediately feeds the other RCBOs.
Is this allowed with a TT system? If not, which level of RCD protection is the minimum required (eg time lag, higher current?). Ideally we would want no RCD between ATS and CU, but the electrician said this is not possible.
Any advice appreciated