Problem replacing pull chord switch in bathroom

[jonesie]

Hi, after looking through the wiki, and searching the site for similar topics, I'm at a bit of a loss,

I have just replaced the light and pull chord switch in my bathroom, all was going well, I had screwed everything back into place so I went to turn the electricity back on at the mains, when I went back into the bathroom the new light was already on, so I thought so far so good, then when I went to pull the chord to turn the light off, it tripped!

I made sure the electricity was off and then checked all the connections again and made sure everything was where it was supposed to be, all seemed to be correct, so tried again and the same thing happened.

The wires from the ceiling for the pull switch are as follows:
1 black wire which I attached to L1
1 red wire which I attached to COM
1 earth wire which I sheathed in green and yellow tape and attached to the unit

After several checks of all the connections, the same thing keeps happening!

Has anyone any idea where I'm going wrong?

 

[Aragorn84]

have you connected the earth wire to the earth terminal, or to L2?

 

[jonesie]

No mate, sorry I should have clarified, I attached the earth wire to the little brass connection point inside the plastic unit, which is assume is the earth terminal

 

[EFLImpudence]

I suspect you have rewired the light incorrectly.

It should be similar to these:

 

[Aragorn84]

Ah missed that he'd changed the light as well!

Yeh in that case you've probably put all the "blacks" together at the light fitting, and this isnt correct!

 

[jonesie]

Hi, thanks for the guide, but the light works fine, it's just when I pull the chord to turn it off, it tripps!

 

[EFLImpudence]

Hi, thanks for the guide, but the light works fine,

No they don't.

when I went back into the bathroom the new light was already on, so I thought so far so good, then when I went to pull the chord to turn the light off, it tripped!

 

[jonesie]

Aragorn84, yes you are correct, I did put the blacks together at the light fitting! I take it that this is the problem? How do I rectify it?

 

[jonesie]

EFL, sorry I'm not following, no they don't what?

 

[EFLImpudence]

You said the lights work fine - they don't.

In the diagrams, at the ceiling rose there is a black wire with a red sleeve.
It would appear that you have put this wire in with the other blacks and have connected the light to the reds.

You will likely need a multimeter to determine which is this black.

 

[jonesie]

When I took the old light down, there were two sets of wires coming from the ceiling, and the two reds were twisted together, and the two blacks were twisted together, I assumed the reds were live and the blacks were neutral and connected them to the new light accordingly!

 

[EFLImpudence]

Are you sure the blacks were twisted together?

If so, then something else has gone wrong.

 

[jonesie]

I'm not a 100% sure they were to be honest mate, I'm still none the wiser

Correct me if I'm wrong, after looking at the diagram bottom right, am I right in thinking that the two reds go together, and one of the blacks goes in with the reds?

 

[PrenticeBoyofDerry]

Do you have pictures of the wiring at the light and at the pull-cord switch?
When you replaced light and switch did you require to drill or screw the fittings in, using different fixing positions than the existing ones?

 

[PrenticeBoyofDerry]

Correct me if I'm wrong, after looking at the diagram bottom right, am I right in thinking that the two reds go together, and one of the blacks goes in with the reds?

The switch live (sometimes black but should be identified as the switch line by marking), would go to the live side of the ceiling rose, together with the brown core of the flex is.

But you have said that all blacks were twisted together as where the two reds.
If you placed them in live and neutral terminals as they were, the light should work.

I guess that you have the two reds as a live loop, one black is neutral and one black is switch live/line. The light is on permanently as you have placed the live loop in the switch side of the light and the switch line with the neutral in the in neutral side of switch. When the switch is open/off the light will be on, as soon as you switch to closed/on, you create a short circuit, which equals tripping of circuit.

Please note: not all light fittings come with a live loop terminal and often you have manufacture that, by use of a terminal connector.