BS88 max ZS table for fuses over 63A TT or not TT

[pc1966]

Overloads are already provided in the controller.

It is for fault protection, and to prevent a fault taking out the DNO fuse (which is basically the same as protecting your own 100A fused-switch).

The run should not be anywhere near 100m...
More worryingly for me right now is that our answers do not match, inclined to think that it is my maths not yours .

Try it with some of the numbers I just did to see if they agree at all, I can post my script later as text if anyone wants to play with it. In the mean time I re-ran a manual calculation for the solution my script found and it seems to make sense.

 

[pc1966]

OK, got my script and edited to add end-of-cable result, ran with your values:
Enter line R1 in mOhm/m .55
Enter CPC R2 in mOhm/m .55
Enter armour R2 in mOhm/m 1.6
Enter length in meters 100
Maximum fault R1+R2 = 0.097 at 90.4 meters
End fault R1+R2 = 0.096 at 100.0 meters

 

[John-]

OK, got my script and edited to add end-of-cable result, ran with your values:
Enter line R1 in mOhm/m .55
Enter CPC R2 in mOhm/m .55
Enter armour R2 in mOhm/m 1.6
Enter length in meters 100
Maximum fault R1+R2 = 0.097 at 90.4 meters
End fault R1+R2 = 0.096 at 100.0 m