Hi there everyone. Got a question hopefully you can help with. Doing a job at the moment and have come across a switch wich seems to turn a extractor fan on/off, when opening the switch I came across two 1.5mm T+E cables with the Lives connected in a seperate choc bloc and both neutrals in either terminal of the switch and both earths also choc blocked. When testing cables obviously both Live cables were live when fan was OFF and so was the Neutral in the common terminal and neutral in L1 was dead, but when fan switched ON both neutrals become dead. How can this be???
dodgy switch
- Thread starter macloon
- Start date
Are you testing this with a volt stick?
Because the neutral is interupted wrongly by a single pole switch, the electricity can't return to neutral.
When a circuit is properly connected, the neutral isn't live. If you put a break in that neutral it becomes live.
Obviously it sounds like you need to put the neutrals in a connector block, and the lives through the switch.
Because the neutral is interupted wrongly by a single pole switch, the electricity can't return to neutral.
When a circuit is properly connected, the neutral isn't live. If you put a break in that neutral it becomes live.
Obviously it sounds like you need to put the neutrals in a connector block, and the lives through the switch.
If it's a S/L then it wouldn't be a neutral. It may be black (or blue) but it wouldn't be a neutral. In this instance it should be sleeved with a piece of red or brown sleeving.
However, in your case it would APPEAR the blacks are neutral. On a single pole switch you only switch the live, and not the neutral.
If in doubt get an electrician.
A volt stick will confuse you in many situations, like this.
If the switch IS in the neutral then when the switch is open, the neutral from the fan will become live as the live will arrive on the neutral though the fan's motor windings.
Get a multimeter and you'll be able to see what is really going on.
PS, just because a conductor is coloured blue (or black) does not necessarily make it a neutral. Its just a black, or blue wire.
Could be neutral, could be switched live, might even be a permanent live that some cowboy did not mark properly.
If the switch IS in the neutral then when the switch is open, the neutral from the fan will become live as the live will arrive on the neutral though the fan's motor windings.
Get a multimeter and you'll be able to see what is really going on.
PS, just because a conductor is coloured blue (or black) does not necessarily make it a neutral. Its just a black, or blue wire.
Could be neutral, could be switched live, might even be a permanent live that some cowboy did not mark properly.
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