Ok... here's another Factory.... (huge automated processing plant).
I had a Chief Engineer above me, (he was non electrical), who could not understand (or be told)
why the main 1,500 amp factory feed was grossly overheating. (Split into 2 parallel sets of cables).
It came down to SIMPLE Ohms Law... :-)
Two 800-amp cables, (each phase), piggy-backed together Lugs, to one side of the huge BusBars.
Unbolted, I calculated about .6 Ohm on one run, and about .3 Ohm on the other runs. Ok....
Sounds like nothing, but ONE had TWICE the current flow as the other !!!!
(1000 amps in one, and 500 amps in the other). Due to a difference of just .3 Ohm...
They either 'get it' or they dont...
Which connection was not crimped properly then? Did the lug glow or not.
Sorry about the delay mate..... (No, but they were unusable). There were multiple issues from memory.
The cable runs took different directions/paths due to availability of various concrete 'holes'. (Lengths!!).
Some Lugs were slightly the wrong size for the cable entries !... but here's the main 'NoNo' reason......
Each 'pair' of Phase Lugs were bolted 'Stacked', to one side of the BusBars !!!! (Can't remember 'washers').
I re-routed/shortened some cables, replaced/re-crimped quality lugs with a proper 100-ton tool.....
And re-bolted using appropriate conductive grease with 1 lug "Either-Side" of the BusBars in direct contact.
The problem went away.... I would have discussed alternatives, due to the high requirement/loading, except
that some departments were being moved off site, so the total plant load was diminishing.