Crossed Polarity smart meter into mains

[telectrix]

went to a similar situation about 30 years ago, when the DNO and the supplier were one and the same. meter fitter has crossed the polarity and it was fine for several months. then a short circuit on the immersion heater occurred. result was a fire which destroyed the upstairs of the house. luckily nobody was injured, but the DNO received a hefty bill and a H&S investigation was carried out. don't know if anyone was sacked as it was a sort of nationalised industry then. sack an idiot and the whole workforce came out on strike. God bless Maggie .

 

[Pete999]

Not only is the reverse polarity a serious meter installation fail it would appear from the only photograph shown that the cut out tails appear to be 16mm on the neutral and 25mm on the live, another fail.
All black cut outs are also reportable to the DNO as a MOCoPA C17 code as their construction materials can result in them becoming conductive leading to a detectable surface voltage being present.

Better change that cut out to a Wallaby one then ,if the All black one s are outlawed.

 

[HS2018]

Thank you for the info, Funnily enough the DNOs fuse blew a few minutes before the electrician cut the electricity- he didn’t know why and said it was too much of a coincidence but as he wasn’t allowed to touch it, he couldn’t change it to see. Also didn’t get any answers as to why this happened from the contractor as he wasn’t allowed to answer many of our questions, as requested by his superior on the phone. QUOTE="Strima, post: 1365893, member: 54489"]@HS2018 two scenarios as an example.

1. Depending on the supply to your installation reverse polarity could have potentially caused a fire under short circuit conditions as the circuit protective device would have been in the neutral and the only device protecting that circuit would have been the DNOs fuse which may not have operated in time.

2. Your better half has been nagging you for a couple of years to change the light in the living room so you decide to change it with an Ikea special. You turn off the circuit breaker and start to rip out the ceiling rose as you assume the circuit is now dead. However you haven't carried out the safe isolation process and as the neutral has been switched off the circuit is still live. Big blue flash and you're on the floor getting measured up for a pine box.

In short reversed polarity is a risk to life and property.[/QUOTE]

 

[stevels4]

Better change that cut out to a Wallaby one then ,if the All black one s are outlawed.

I didn’t say they were “outlawed” they are just reportable under MOCoPA to the DNO

 

[Octopus]

In short reversed polarity is a risk to life and property.

As I previously stated, in a domestic situation there are extremely few occasions where reversed polarity is dangerous ............. and obviously you would always isolate the circuit before you fiddled...

Having no earth is a bit more serious ............

When our meter was replaced a few years ago, the installer who did it, checked the polarity with one of the plug in testers before he did the work and afterwards.

Just saying.

 

[johnduffell]

In domestic reversed polarity must be dangerous.

Things are designed to need two problems before you get killed. This takes many aspects of the install to only need one thing wrong.

Never mind single pole isolators not working, and polarity on ES fitting being wrong, all the fault protection is in the neutral thus useless.
Rcds are usually dp, but in an all RCBO install that's not present either.
Only thing worse would be a tn-c-s earth coming from the line...

 

[johnduffell]

Duplicate, sorry!

 

[Pete999]

In domestic reversed polarity must be dangerous.

Things are designed to need two problems before you get killed. This takes many aspects of the install to only need one thing wrong.

Never mind single pole isolators not working, and polarity on ES fitting being wrong, all the fault protection is in the neutral thus useless.
Rcds are usually dp, but in an all RCBO install that's not present either.
Only thing worse would be a tn-c-s earth coming from the line...

You uping your post as well mate (a joke)

 

[johnduffell]

Sorry no idea, blame my phone for being slow

 

[stevels4]

As I previously stated, in a domestic situation there are extremely few occasions where reversed polarity is dangerous ............. and obviously you would always isolate the circuit before you fiddled...

Having no earth is a bit more serious ............

When our meter was replaced a few years ago, the installer who did it, checked the polarity with one of the plug in testers before he did the work and afterwards.

Just saying.

The correct procedure is to check for correct polarity at the cut out and meter connections using a none contact voltstick, then check for correct polarity at the CU using the voltstick across the live busbar or MCBs and then use a socket tester to confirm at a socket. After installation of the new meter the tests are performed again using the same socket.

 

[Pete999]

The correct procedure is to check for correct polarity at the cut out and meter connections using a none contact voltstick, then check for correct polarity at the CU using the voltstick across the live busbar or MCBs and then use a socket tester to confirm at a socket. After installation of the new meter the tests are performed again using the same socket.

Really? are you sure about that steve? volt stick, same socket?

 

[littlespark]

Even if there was no testing performed like it should be, visually its fairly simple to trace which tail goes from service fuse, through the meter/Henley block, isolator whatever and into the right terminal on the CU main switch.
Maybe the outer sheath of the cables used should be coloured brown or blue instead of both in grey.

 

[telectrix]

should not the so called "smart " meter have detected the reversed polarity? if it could then that would give them a purpose in life apart from snooping.

 

[Pete999]

should not the so called "smart " meter have detected the reversed polarity? if it could then that would give them a purpose in life apart from snooping.

They aint that smart Tel, neither it seems, are the installers, sorry Engineers. No not sour grapes before anyone cottons on.

 

[telectrix]

know what you mean pete. some while ago BG wanted sub-contract sparks for electrical repairs/call-outs. i was turned down. apparently a HND in Electrical Engineering coupled with 2382 and 40 years experience, is not a suitable qualification for them. but a Electrical Trainee would have got the jobwith a "part pee qualification".

 

[Pete999]

know what you mean pete. some while ago BG wanted sub-contract sparks for electrical repairs/call-outs. i was turned down. apparently a HND in Electrical Engineering coupled with 2382 and 40 years experience, is not a suitable qualification for them. but a Electrical Trainee would have got the jobwith a "part pee qualification".

Over 60 end off

 

[sparksburnout]

As I previously stated, in a domestic situation there are extremely few occasions where reversed polarity is dangerous ............. and obviously you would always isolate the circuit before you fiddled...

Having no earth is a bit more serious ............

When our meter was replaced a few years ago, the installer who did it, checked the polarity with one of the plug in testers before he did the work and afterwards.

Just saying.

I really don't know where you are coming from regarding this. Of course it is dangerous!

 

[stevels4]

Really? are you sure about that steve? volt stick, same socket?

Please elaborate, non contact probe/voltstick to check cut out fuse is live, same device on meter tails (conductors) and CU. Socket test is always at the same one beginning and end of installation, if it tests correctly at the start it should, if the polarity is still correct, retest correctly at the end of the job.
In other words the tests are performed on a known good socket.

 

[Octopus]

I really don't know where you are coming from regarding this. Of course it is dangerous!

As I previously stated, only if somebody is doing something "live" when it should be isolated.....

Tell me how its "dangerous" in a normal domestic installation?

 

[sparksburnout]

As I previously stated, only if somebody is doing something "live" when it should be isolated.....

Tell me how its "dangerous" in a normal domestic installation?

As Strima has already outlined. Yes, in the perfect world where everyone practices safe isolation and assumes nothing, then it should not ever happen that a person touches anything that is live. But, seriously, have you never touched a neutral without putting your tester on it? Never?? And of course, there is the risk to those who do not practice such things, it might not be right, but it happens, and under those circumstances it is very dangerous. You can't live in a perfect world, because the world is not, perfect. I don't believe any spark that say's he has never ever touched a neutral without testing it.