test for phase sequence

[jamie-spark]

There is an article in this months PE about this. Basically phase verification tested by means of polarity testing between DB's ect

 

[plugsandsparks]

It is interesting to have the new tickbox on the certs as I had a factory the the board had connected wrongly so every machine had to be reversed which made alterations a nightmare when some items really did need reversing on supply, I phoned DNO and they could not be bothered about it and would not come out to change back. I would have done it myself but it was a 400A intake so was on CT so not so straight forward.

Similar situation. Was doing a condition report and my meter was showing 321 at the MDB, traced back to the incoming from distributor and sure enough even though its a newish supply, 400A and colour coded, still getting 321. Its been in for around 5 years so dont expect any action from supplier and also dont fancy correcting about 30 machines, problem i have is that i now have to install a new 200A board, do i install it 321 or correct the sequence for just this board, any ideas guys ?
thx