lost/loose neutral???

[LarkySparky]

Right....

Have a light wired in 3 plate,

1 feed in ( from cu ), 1 loop out ( to other lighting circuits on the floor level - all functionally working ok ), 1 switch line and a load out (light, which is also functionally working ok)

If all loads/loops are disconnected and i am left with the feed i get the following:

L - N 240v

L - E 50v

N - E 50v

When all is connected up again i get the following:

L - N 50v

L - E 0v

N - E 240v

The installation is about +- 6 years old ( spoke to the owner )

I'm a little baffled as everything works fine, obviously lamp replacement is quite frequent cause of the back feed through the neutral.

The installation is obviously not safe and remedial work is imperitive, as i advised the owner (periodic needed). standard of previous work is not the greatest.

what could be the cause of these odd readings, i haven't come across anything quite like that before?? any ideas?

 

[LarkySparky]

Right....

Have a light wired in 3 plate,

1 feed in ( from cu ), 1 loop out ( to other lighting circuits on the floor level - all functionally working ok ), 1 switch line and a load out (light, which is also functionally working ok)

If all loads/loops are disconnected and i am left with the feed i get the following:

L - N 240v

L - E 50v

N - E 50v

When all is connected up again i get the following:

L - N 50v

L - E 0v

N - E 240v

The installation is about +- 6 years old ( spoke to the owner )

I'm a little baffled as everything works fine, obviously lamp replacement is quite frequent cause of the back feed through the neutral.

The installation is obviously not safe and remedial work is imperitive, as i advised the owner (periodic needed). standard of previous work is not the greatest.

what could be the cause of these odd readings, i haven't come across anything quite like that before?? any ideas?

 

[Bez]

would start with a few continuity tests to check all is what it seems

 

[Bez]

would start with a few continuity tests to check all is what it seems

 

[Evans Electric]

What other tests have you done , Malarky? Polarity ? Is the earth connected ? Is the neutral connected at the board ?

 

[Evans Electric]

What other tests have you done , Malarky? Polarity ? Is the earth connected ? Is the neutral connected at the board ?

 

[steptoe]

to start with you need to make sure this is the 1st light on the circuit and take your readings again.

the readings you have show 190v on the E across Line, NOT good.

but I dont think this is correct,

looks more like reverse polarity to me, and your LN reading is actually a NL reading with simply an induced current on the earth,

deffo needs more thorough testing.

 

[steptoe]

to start with you need to make sure this is the 1st light on the circuit and take your readings again.

the readings you have show 190v on the E across Line, NOT good.

but I dont think this is correct,

looks more like reverse polarity to me, and your LN reading is actually a NL reading with simply an induced current on the earth,

deffo needs more thorough testing.

 

[kme]

Concur with Steptoe - Either test more thoroughly, with some cont / ins. readings; or have it "fault-found" professionally ;0

n.b. it will ALWAYS help to provide as much info as possible - you`ve seen it, we haven`t. What is the earthing system? Do you have a Ze / Ra reading ; and a polarity confirmation? What "CU" is it, (type, not make).

obviously lamp replacement is quite frequent cause of the back feed through the neutral.

What "back feed" are you describing?? I don`t understand.

The installation is obviously not safe and remedial work is imperitive, as i advised the owner (periodic needed).

Sorry - that makes no sense to me; though I HAVE had a rhum or two this evening ; ). Could you expand on these comments, for a poor old sparky who can`t get his head round this new-fangled "back-fed neutral" malarkey? Thanks

KME

 

[steptoe]

Concur with Steptoe - Either test more thoroughly, with some cont / ins. readings; or have it "fault-found" professionally ;0n.b. it will ALWAYS help to provide as much info as possible - you`ve seen it, we haven`t. What is the earthing system? Do you have a Ze / Ra reading ; and a polarity confirmation? What "CU" is it, (type, not make).

What "back feed" are you describing?? I don`t understand.

Sorry - that makes no sense to me; though I HAVE had a rhum or two this evening ; ). Could you expand on these comments, for a poor old sparky who can`t get his head round this new-fangled "back-fed neutral" malarkey? Thanks

KME

I think its a back fed "live" myself

 

[kme]

Ah - that makes it clearer, then. Thank you Albert.

(n.b. r.e. PM - however many, its now +1.) /.- ... .----/

-.- -- .

 

[Sidewinder]

Ah - that makes it clearer, then. Thank you Albert.(n.b. r.e. PM - however many, its now +1.) /.- ... .----/

-.- -- .

Eh?...

 

[steptoe]

Eh?...

catch up man.!

 

[kme]

Eh?...

What? D`you miss it, or summat?

 

[Chr!s]

Is this a tt installation?

 

[Evans Electric]

The world awaits any further input , Malarky !!

 

[m4tty]

The world awaits any further input , Malarky !!

Come on malarkey mate the suspense is killing .....