Electric shower help

[paradisiac]

hi, just to start out, im not an electrition so please be nice
a week or so back our shower stopped working completly. we have a power cable from the electric meter box thing to a switch in the airing cupboard, and then a cable from there to the shower. the light comes on on the switch in the cupboard IF the shower is turned off, but as soon as you turn on the shower the light goes off. ok, so we thought dead shower as it was cheap, so purchased a new one. fitted it and same issue so i got out the trusty multimeter and did some tests.

electric meter to switch :
+/N = 240v
+/E = 240v

switch to shower :
+/N = 64v
+/E = 240v

not sure if any of this makes any sense or is any use at all, but i am stumped as to what to do now.

 

[RMS]

Possible faulty switch.

Neutral contacts probably open circuit (faulty).

Replace the switch.

 

[paradisiac]

Possible faulty switch.

Neutral contacts probably open circuit (faulty).

Replace the switch.

thankyou, that is what we were hoping. how safe would it be to twist the cables to test it, i know 240v is quite alot to play with.

 

[pjcomp]

Your description of the light on the switch being OFF when the shower is on and ON when the shower is off suggests that the load/supply conenctions in the switch have been reversed, which is not wrong but is confusing. Te fact the shower stopped working and the mter readings you're getting (despite fitting a new shwoer) suggest the wiring in the switch needs a good looking at - likely the neutral is loose. Is the insulation on any of the wiring in the switch blackened and flaking?

PJ

 

[paradisiac]

Your description of the light on the switch being OFF when the shower is on and ON when the shower is off suggests that the load/supply conenctions in the switch have been reversed, which is not wrong but is confusing. Te fact the shower stopped working and the mter readings you're getting (despite fitting a new shwoer) suggest the wiring in the switch needs a good looking at - likely the neutral is loose. Is the insulation on any of the wiring in the switch blackened and flaking?

PJ

checked the switch and everything seems to be ok, nothing feels loose or looks damaged in any way.
in reference to the light on the switch, this is not wired backwards. we have to turn on the switch to get power to the shower, and then turn on the shower. if the shower is turned off, the light comes on to show that power is getting upstairs, but when the shower turns on it makes the light go out, which made me think it was trying to draw too much power or something.

 

[RMS]

I suppose you could try and wire both cables into one side of the switch if they fit.

eg. Use the L and N feed terminals and wire both lines into L feed and both neutrals into N feed. Assuming they will fit of course.

 

[paradisiac]

I suppose you could try and wire both cables into one side of the switch if they fit.

eg. Use the L and N feed terminals and wire both lines into L feed and both neutrals into N feed. Assuming they will fit of course.

couldnt get both into one terminal, but when i took the switch apart to check it, i noticed that the terminals that we were having issues with were black (on the underside of the switch not the part you see when removing the rear panel. alas it had a spring in it and now its in a million pieces and i cant work out how its meant to be so will have to wait til morning and get a new switch. any reason why this would happen?

 

[RMS]

Cheap switch possibly. Its quite common.

Change the switch and make sure you connections are nice and tight.

 

[paradisiac]

Cheap switch possibly. Its quite common.

Change the switch and make sure you connections are nice and tight.

on the switch it say 250v 45a, is this normal for a switch, dont want to get one too high or too low.

 

[RMS]

Yes its normal.

Get a 45A switch or 50A.

 

[paradisiac]

wired in a new switch and shower now works fine. thanks for your help.