Ring Main Zs

[steptoe]

type 3 is 10x current

240 / 320 = .75. x0.8 = .60

thats assuming a 32a MCB

perhaps as likely a 30a as its a type 3

as above, a load more info needed

 

[Andy™]

good chance it is 30a

 

[Sidewinder]

jimmymac,

We need the model of the SqD mcb & the rating, as certain models of Type 4 has a max Zs of 0.6 thus the Type 3 should be higher.