Adiabatic Equation

[DYCHE4230]

Hi All,

Can anybody help....Trying to establish if I would have to change the mec on a TNS system....

Ok So S=sqr(I2xt)/k

When establishing the value of 't' do I use the characteristics of the distibutors main fuse or the main switch in the CU or I have missed the point entirely?

And when establishing 'I' do I use 230v or 240v

Some direction in this matter would be most helpful.

Thanks in advance.

 

[uksel]

i think you have to use the value of the main fuse.

use 240v, that is still currently the UK energy providers output voltage, and is likely to be for a long time as they are making more money out of us this way

 

[RETIREDSPARKY]

Why are you trying to calculate the size of mec when you should be using table 54.7 in relation to meter tails[largest size conductor].

 

[DYCHE4230]

Why are you trying to calculate the size of mec when you should be using table 54.7 in relation to meter tails[largest size conductor].

Hi, I don't want to change the existing MEC if I don't have too. So was gonna check if the existing is adequate if not then I'll upgrade them as table 54.7

Thanks for your quick replies....