Hello, isolator switch help

[colin inglis]

Hello
My first post on my first job...
I have just installed an extractor fan. It was going to have a timer but the house wiring is confused: the switch and light are not connected directly, instead the cables go off under the floor boards and yet the switch is 50cm from the switch??
So the light and socket both have blue tape around the neutral wire indicating switch lives? My guess is there must be a junction box somewhere?
All of the test values were fine, until I opened the isolater switch. The value was below the 1 meg minimum, and a similar value from the extractor when switched off at the isolater. When switched on and working I get 0.48 ohms.
Should the extractor be connected to the pull cord instead of the ceiling rose, which only has a line and switchline.
Is it possible the isolater has a fault? It is a schlumberg which I thought reliable. Any and all help gratefully received

 

[westward10]

Think you need to be clearer as to what you are asking.

 

[Baddegg]

Ummmmmmmmmmm?

 

[littlespark]

but the house wiring is confused:

I know how it feels.


Would it be possible to see a photograph of the connections at the switch, light and fan isolator.

 

[Charlie_]

1 thing I think I might have worked out is that you are doing an ir test on the fan?
Don’t be doing that now

 

[Baddegg]

Post some pics up Colin it’ll definitely help

 

[colin inglis]

I know how it feels.


Would it be possible to see a photograph of the connections at the switch, light and fan isolator.

The fan has just two terminals: Line and Neutral. It is double insulated so the earth isn't used.

The Light is on the main board. The pull switch also has only one cable coming in. No connection to the light. I wish it did, I would have finished a day earlier and not had to plaster a section of ceiling. Not quite what I expected for my first job...

 

[colin inglis]

1 thing I think I might have worked out is that you are doing an ir test on the fan?
Don’t be doing that now

An IR test might have got me an early finish! It was just continuity test between Line and Neutral, I was wanting to confirm the isolater switch was working.

 

[westward10]

I keep reading your first post and really cannot grasp what you are getting at.

 

[casperLennon]

What is the socket you mention?

 

[colin inglis]

What is the socket you mention?

This is a bathroom light socket.

 

[PEG]

I think the answer is 42.

 

[colin inglis]

I keep reading your first post and really cannot grasp what you are getting at.

Apologies it is not ver clear. I carried out continuity testing at the isolater switch and extractor fan. When turned on it was fine. When the isolater was turned off it gave a reading. At all other parts of the circuit, when the power was off I got a reading greater than 19.99M Ohms as expected. After the isolater it dropped to less than 1M ohm.
Surely this reading should be higher?

 

[colin inglis]

I think the answer is 42.

Certainly explains the existing wiring

 

[colin inglis]

The fan has just two terminals: Line and Neutral. It is double insulated so the earth isn't used.

The Light is on the main board. The pull switch also has only one cable coming in. No connection to the light. I wish it did, I would have finished a day earlier and not had to plaster a section of ceiling. Not quite what I expected for my first job...

I have posted a picture but it hasn't turned up yet??

 

[westward10]

Apologies it is not ver clear. I carried out continuity testing at the isolater switch and extractor fan. When turned on it was fine. When the isolater was turned off it gave a reading. At all other parts of the circuit, when the power was off I got a reading greater than 19.99M Ohms as expected. After the isolater it dropped to less than 1M ohm.
Surely this reading should be higher?

Continuity testing is carried out at the ohms scale not Mohm. Are you doing insulation resistance testing. As for the neutral wires having blue tape on them indicating switch live did you not test them to verify.

 

[Wilko]

Hi - is the new fan still connected during the IR tests?