For all sparkies on the board

Who hates neutral feedback?

Had a lovely belt off 240v and shut down a water pumping station. And it was a simple "go change a generator battery charger". Disconnected the old charger with nothing between live + neutral and neutral + earth (fuse pulled) and then hear the pumps inside start to wind down and start up and then finding 240 on neutral, not happy. Neutral had gone live on the generator heater, battery charger and no way to isolate without dumping mains. I'd tried turning everything else off in circuit but no neutral still live and drawing shows mains isolator doesn't switch the neutral either so i must of caused a fault on the grid. Oops. This will be fun to sort monday morning.

[DarrenSV650S]

Don't really understand what you mean. What was causing the feedback?
But yeh, neutral feedbacks are very very bad

I hate working on old/dodgy wiring. One of the university building we were working in had really old "circuit breakers" that didn't really work. There was a dead short in one of the light switches and the breaker didn't even trip Scary to think how long you'd be holding on to that wire if you got a zap

Originally Posted by DarrenSV650S

Scary to think how long you'd be holding on to that wire if you got a zap

[----------------------------------------------------]

This long?

[DarrenSV650S]

Possibly

[andrewsmith]

not good.

Sounds like a whole site of dodgy wiring or the pikeys are stripping the site. Its happened in mid-ish Wales in the last 6 months
So... how big an area u kill the juice to?

I dunno how big. But it was back on. Basically having 240v on the neutral is bad even more so when you got a lot of things on the same circuit which to change you need to shut the place down. It's just how it's wired. I've seen it on old lighting circuits. Just waiting for an **** kicking monday morning.

[timwilky]

My dodgyist one was when installing a UPS within a transformer room.

When it wouldn't sync we realised there was a wrong phase rotation on the bus bars. Only been there for 80 years.

So do we correct the old wiring from the transformers( Ironically made within our own factory and shipped up onto the office block roof, so you would have thought we should have known something about wiring them up).

After a quick agreement that nothing in the office block used 3 phase supplies we decided it best to shut down the substation and correct the fault.

Monday holy hell broke out. The fans in the canteen ovens had turned to suck instead of blow mode.

Yep sounds about right. But at least it was being put in a warm room where as they basically stick the UPS outside where i work and wonder why they fill with water.