PDA

View Full Version : Neutrel switching



wizzer
18-06-2006, 04:15 PM
:confused: Thanks for your thoughts the last time i visited the forum,ive decided the engineers route, problem is ive hit my first brickwall?

I,m fine with live switching and fault finding but how do you test a circuit that controls by switching NEUTRALS with my multi meter.

any help much apprciated.

frank
18-06-2006, 06:33 PM
Can you give us an example of a circuit that uses neutral switching in the UK?

rbartlett
18-06-2006, 07:12 PM
Can you give us an example of a circuit that uses neutral switching in the UK?

A lot of old Italian counters plus the odd American bit switched on the netural...it can be very difficult as we are trained to look for the end of the 'live' to find where the fault lies but with neutral switching it can be very confusing and potentially lethal..

For testing a t.stat for example. the 'dead' leg will -supposedly-be incoming, the way is to put the tester either side of the switch and check for voltage across as you would normally.

It can be best to work from the live side and see where it goes dead you just have to be a bit more careful.

For practise if you have a working cabinet accessible to play with, just swap the live for the neutral in the plug and see what happens

cheers

richard

frank
18-06-2006, 07:53 PM
I've only come across a neutral switch once. It was on an old American time clock. Strange way of doing it, and as you say, it could be dangerous. Goes against all your instincts when trouble shooting. :)

wizzer
18-06-2006, 09:50 PM
I;ve come across this problem on 2 new zanussi cabinets this week alone and they were commercial cabinets,also on a Zanotti coldroom.I will try your idea Richard of swapping the plug wires if it goes bang ne sweat.

cheers

Wizzer

smoggy
21-06-2006, 06:08 PM
Is switching the neutral, not against IEE regs

Latte
21-06-2006, 09:44 PM
Hi Guys

Reeferjon and MRW will know more about this than i do but i am sure some TK SR units use neutral switching on the control circuits

Regards

Fatboy

NoNickName
22-06-2006, 10:37 AM
PE switching is against the regulation, not neutral switching.

bill1983
22-06-2006, 10:53 PM
if you follow the control circuit from the end backwards wouldn't the break be showm by a backfeed of 240v or whatever the control voltage is.
i do agree that live switching is easier to follow but a lot of continental cabinets used to be neutral switched and as long as there were no electronic controls we just used to reverse the cables at the cabinet, not in the plug and we always marked the system for the next engineer

happy to help
bill

JimmyMurphy
23-06-2006, 03:27 AM
99% of the mechanical timeclocks used for defrost termination switch on the neutral side, it is one of the rare occasions where it is allowed in Canada.

Decdastardly
15-02-2009, 03:41 PM
I see neutral switching sometimes on icemachines, scotsman mainly it definately makes fault finding awkward..don't really see why they do that -maybe to reduce arcing at the switch was my only thought or maybe just certain manufacturers convention

Grizzly
15-02-2009, 04:03 PM
I see neutral switching sometimes on icemachines, scotsman mainly it definately makes fault finding awkward..don't really see why they do that -maybe to reduce arcing at the switch was my only thought or maybe just certain manufacturers convention

Nice of you to join in Dec.
May I just point out that this post was last added to in June 2006.
Perhaps a newer one next time may have more people contribute?
Welcome anyways!
Grizzly

Decdastardly
15-02-2009, 09:12 PM
Ha! spot the rookie poster!

slingblade
18-04-2009, 12:18 AM
Ha! spot the rookie poster!


its you .