Odd Reading On Martindale

[securespark]

Following the Phase Neutral Reversal post, here's my pic of a Martindale exhibiting a lit neon not explained by the instructions.

 

[EFLImpudence]

That's like the picture in this thread
//www.diynot.com/diy/threads/phase-neutral-reverse-fault-on-kitchen-socket.461502/

Is it your picture? Can you work out what it means?

 

[ericmark]

From the instructions "Your socket tester is not intended to replace good electrical practices" even as a quick test only the EZ150 is really good enough. And they all only use 1.6W or 6.9 mA. As an electrician you should have a full test set.

I have noted the warning about not detecting earth - neutral reversal and in real terms even with a full loop tester detecting earth - neutral reversal without removing supply would not be easy. One may get a warning where the earth loop is lower than the neutral loop but random earth bonding can do that anyway. Only with a TT supply could you be 100% sure.

With a TN supply the neutral link needs dropping to test for earth - neutral reversal.

I have never seen the point in the neon lamp tester, you have an earth loop impedance tester so why use a simple neon tester? Even a minor works certificate needs readings which the neon tester does not provide. So why use it?

I remember before the propriety testers came on the market I did make my own tester for 110 volt split phase, two LED's and a neon plus current limiting resistors and diodes to stop reverse voltage. The LED used more power than neon so all good two LED's and a neon, no earth no LED's but neon still lit, and phase missing one LED would fail. But with 64 volt max to earth that is very different to 230 volt to earth. I have wondered how the plug in testers work, using one in the caravan is near enough. One needs to test every time you plug in. And for allied trades or DIY OK. Yes I know years ago there was one earth loop impedance meter between 20 electricians but one hopes things have moved on.

 

[Taylortwocities]

Doesn't it mean 'open' earth?
What does your proper tester tell you?

 

[securespark]

That's like the picture in this thread
//www.diynot.com/diy/threads/phase-neutral-reverse-fault-on-kitchen-socket.461502/

That's why I posted it.

Is it your picture? Can you work out what it means?

Yes, taken on a job a fair few years ago. My tester would not take an EFLI. I never got to the bottom of it as I disconnected it and the job was revisited by a colleague later in the week.

 

[ban-all-sheds]

That's like the picture in this thread
//www.diynot.com/diy/threads/phase-neutral-reverse-fault-on-kitchen-socket.461502/

That's why I posted it.

Do some of us need a trip to Specsavers?

 

[EFLImpudence]

There is another picture with the switch off which gives just the middle light on.

 

[securespark]

OK. Missed the fact the switch was off.

 

[EFLImpudence]

That presumably means the line IS connected to N or E (presumably N, unlikely E)), or there would be no power to light the tester, so it is reversed polarity at that socket.

 

[ban-all-sheds]

There is another picture with the switch off which gives just the middle light on.

I'll just check their website to see where my nearest branch is....

 

[EFLImpudence]

//www.diynot.com/diy/attachments/single_socket_switch_off-jpg.100800/

 

[ban-all-sheds]

That's the one I missed, partly because the thumbnail cropped it, rather than shrank it, so in the thumbnail there are no lights visible.