M
Martin Wiseman
Hi,
I'm putting in a 20A supply to my garden shed. 10m of 4mm SWA cable from
the house to a small CU containing a 30mA RCD and using a local earth
rod to provide TT earthing.
Clearly the cable connecting to the earth spike doesn't need to have a
particularly great CSA for operational purposes (even the resistance of
1mm cable would be vastly less than the earth resistance of the rod and
more than capable of carrying 30mA), however I was wondering if the
regulations actually specify a minimum cable CSA.
In the absence of specific guidance I will probably use 2.5mm or 4mm
cable.
Can anyone confirm what the regulations have to say on the subject.
Thanks,
Martin.
I'm putting in a 20A supply to my garden shed. 10m of 4mm SWA cable from
the house to a small CU containing a 30mA RCD and using a local earth
rod to provide TT earthing.
Clearly the cable connecting to the earth spike doesn't need to have a
particularly great CSA for operational purposes (even the resistance of
1mm cable would be vastly less than the earth resistance of the rod and
more than capable of carrying 30mA), however I was wondering if the
regulations actually specify a minimum cable CSA.
In the absence of specific guidance I will probably use 2.5mm or 4mm
cable.
Can anyone confirm what the regulations have to say on the subject.
Thanks,
Martin.