Strange Fault Symptoms

[securespark]

Colleagues went to fault today.

Sockets on a butchered RF circuit.

Martindale showing L-E reversal on some sockets not others.

Two pole detector on those LE reversal sockets shows:

LE: 230V

LN: 0V

NE: 230V


Seems very straight-forward now, but when it was described to me over the phone, I knew the cause of the problem but could not explain to my colleague why I had come to that conclusion.

 

[Electrifying]

I don't understand your problem, Securespark.

You've said what the fault was in your third line and then proceeded to give us the symptoms - as if wanting us to solve the fault???

What is it you're trying to say?

 

[JohnW2]

Two pole detector on those LE reversal sockets shows:
LE: 230V (i.e. true E-L = 230V)
LN: 0V (i.e. true E-N = 0V)
NE: 230V (i.e. true N-L = 230V)
Seems very straight-forward now, but when it was described to me over the phone, I knew the cause of the problem but could not explain to my colleague why I had come to that conclusion.

Am I being dim? That seems exactly what one would expect from an L-E reverse (as above in red). What problem am I missing?

Kind Regards, John.

 

[Electrifying]

SNAP

 

[JohnW2]

SNAP

Indeed, even identical posting times

Kind Regards, John.

 

[securespark]

Hmm... my postings tonight have been encrypted by Captain Fog. Sorry.

The Martindale gave the fault as LE reversal, but the actual fault was NOT LE reversal.

Now can you deduce what it really was??

 

[Electrifying]

All conductors were rotated - i.e. L in E, E in N & N in L.

The martindale socket tester can't read a Neutral/Earth swap, so gives a reading of Line/Earth swap only.

 

[JohnW2]

Hmm... my postings tonight have been encrypted by Captain Fog. Sorry. The Martindale gave the fault as LE reversal, but the actual fault was NOT LE reversal. Now can you deduce what it really was??

Are you sure you're not depriving us of some important information? If the Martidale showed LE reversal, and your two-pole detector voltages 'confirmed' that, then there must surely have been something else (which you're not telling us!) that caused you to even think that the actual fault might be something different from LE reversal?

Kind Regards, John.

 

[Electrifying]

If I'm correct - and they trusted the readings and swapped Line & Earth (without checking markings on sockets), then they would have been left with a Line/Neutral reversal.....which would have then shown on the martindale. (and probably puddled their brains.)

You just can't beat the proper RFC figure of 8 test!

 

[securespark]

Nope, I'm not depriving you of any info! I'm not trying to be obtuse! Just a little teaser to see if you can work it out.

My colleague rang, told me he had the Martindale reporting LE reversal at certain sockets, so he then checked at those sockets and found the reported voltages between those conductors.

That's all the info. he gave me to go on.

Just to clarify, which may not have been 100% clear from my previous postings, some other sockets tested normally.

 

[Electrifying]

And my diagnosis, securespark??

All conductors were rotated - i.e. L in E, E in N & N in L.

The martindale socket tester can't read a Neutral/Earth swap, so gives a reading of Line/Earth swap only.

 

[JohnW2]

All conductors were rotated - i.e. L in E, E in N & N in L.
The martindale socket tester can't read a Neutral/Earth swap, so gives a reading of Line/Earth swap only.

Yep, I reckon that would do it - but I still don't understand why securespark thought any further when all the evidence appeared to indicate a L-E reverse! If you're right, it's just as well that he did, though!

Kind Regards, John.

 

[EFLImpudence]

Whether rotated as Electrifying wrote or

just an L - E reverse the readings would be as stated.

I'm still not sure what the question is.

 

[RF Lighting]

I've only just seen this thread, but it seems really obvious to me that the fault is simply an open circuit neutral and there is a load connected to the circuit somewhere.

I can't beleive no one else worked that out

 

[securespark]

Full marks to Rob!

As I said, the fault initially appeared to be LE reverse, but was not. IT was indeed an open neutral with a load in circuit.

Sorry to disappoint the LE reversal supporters!