You need scrambled brains to sort this!

[Knobhead]

Known it to be called a bus coupler as well

Bus tie, bus-coupler, bus section,,,,,,, All the same flavour. The Indians favour bus-tie, the Americans bus-coupler.

 

[Chr!s]

No neutral, no star point, unbalanced loading Affecting voltages.

 

[Knobhead]

OK first clue:

Think of neutrals and CU's

 

[plugsandsparks]

Wild guess, their CT wiring is wrong way round

 

[Guest123]

Substation 2 is getting it's 3 phases from ACB1 whilst the neutral is returning on ACB2 due to the bus-coupler being open giving unbalanced loads as they're 1P???

 

[johnboy6083]

is this a TNC system?

 

[ian.settle1]

No neutral 400v across single phase equipment

 

[johnboy6083]

thats kinda the route im thinking, the lost neutral situation, neutral currents returning via the metalwork. Does this system incorporate phase failure relays that would shunt trip the ACB on voltage imbalance?
where are the neutral-earth bonds for the star point of the tx? if any

 

[Knobhead]

I should have banned you Lenny. In effect it's our old friend a shared neutral.

Here's the drawing I had to do to work it out.

View attachment 14750

 

[Knobhead]

The guy still wouldn’t accept it.
It’s not very often you get a Indian university professor loosing his rag, but he convinced the guy I was right.