How common is reversed polarity?

[pc1966]

Looking over the best practice guide to electrical inspection condition reporting the C1 "danger present" conditions are basically exposed live parts or reversed polarity. I guess the seriousness of reversed polarity is the lack of any meaningful over-current protection for faults to earth.

This forum's thread on dodgy pictures has several examples of exposed wires, etc, but how often have any of you seen a case of L & N swapped at the consumer unit?

 

[casperLennon]

I’ve definitely checked the ones I did after that.

 

[davesparks]

I installed a 12 circuit dimmer a couple of years ago which had the outgoing terminal strip labelled back to front. The terminals were labelled L1, N1, L2, N2 etc but they were connected the opposite way internally N1, L1, N2, L2 etc.

Obviously we found it when we started testing, and in this particular case it wouldn't have been too bad as, due to a suppliers error, we had the version with true double pole mcbs intended for the mainland European market. But a lot of these dimmers get installed without any testing and I dread to think how many of the single pole mcb version were fitted before we brought this to the attention of the manufacturer.

 

[Taylortwocities]

I saw it once. Guy came to fit new washing machine and fortunately used a socket tester. Raised the alarm when it yelled at him.
Tails wrong way round to main switch. Had been like that since a cowboy installed new cu. cannot have been even basically tested. it had been like that for a long time.

 

[Megawatt]

Looking over the best practice guide to electrical inspection condition reporting the C1 "danger present" conditions are basically exposed live parts or reversed polarity. I guess the seriousness of reversed polarity is the lack of any meaningful over-current protection for faults to earth.

This forum's thread on dodgy pictures has several examples of exposed wires, etc, but how often have any of you seen a case of L & N swapped at the consumer unit?

PC I’ve seen lamps with the polarity crossed and it makes the screw in base live and the tip is the neutral which makes the whole metal frame of the lamp energized

 

[ED17]

One of our lads (many moons ago) decided to get the tails the wrong way round on one of the jobs that the NICEIC man was having a look at for our annual assessment!

 

[ipf]

One of our lads (many moons ago) decided to get the tails the wrong way round on one of the jobs that the NICEIC man was having a look at for our annual assessment!

Impressed you found it, then?

 

[ED17]

Impressed you found it, then?

It was one of a block of four flats and the lads managed to sort it while the NICEIC man was watching me testing a ring (rather slowly) in another flat!

 

[FatAlan]

Saw a DNO engineer get tails the wrong way round when fitting an isolator. Fortunately he picked it up when testing.

 

[pc1966]

An interesting amount of feedback, I am surprised by some of it but at least it is good to see cases like that when they test, discover the mistake, and fix it before it is used for real!

 

[Micktw68]

Looking over the best practice guide to electrical inspection condition reporting the C1 "danger present" conditions are basically exposed live parts or reversed polarity. I guess the seriousness of reversed polarity is the lack of any meaningful over-current protection for faults to earth.

This forum's thread on dodgy pictures has several examples of exposed wires, etc, but how often have any of you seen a case of L & N swapped at the consumer unit?

Only seen it once after DNO did a meter change. Only identified by homeowner when the boiler started burning out PCBs