adeabatic equation

[martspark]

Have been told i shud do a adeabatic for all the circuits i put in
When i have a hi pfc they dont pass allthe time
I take pfc at point served (or calculate from V divided by Zs)
then i times it by itself
then i times it by disconection time (0.1 for type b)
then find the square root of that
then divide by cable factor like 115 for t and e

Is this right?

if it is a lot of circuits ive put in dont pass



and with a ring main do you just double the earth size like use both legs?? so if its 2.5 & 1.5 then the earth csa is 3mm?

thanks

 

[pushrod]

Is this right?

if it is a lot of circuits ive put in dont pass

Yes - your method of calculating is correct

When you calculate PFC are you adding R1+R2 to Ze to get your Zs

 

[martspark]

thanks for ansering mate. some times i do as yousay and add r1 +r2 and the ze but some times i take a mesurement.
I was doin it rite then. wish i hadnt been
tannks tho