ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
Do we need grounding?
by tortuga - 03/18/24 08:39 PM
240V only in a home and NEC?
by tortuga - 03/18/24 04:29 PM
Cordless Tools: The Obvious Question
by renosteinke - 03/14/24 08:05 PM
Test Post
by sabrown - 03/06/24 05:29 PM
Solar PV Wiring Errors
by renosteinke - 03/02/24 09:12 PM
New in the Gallery:
This is a new one
This is a new one
by timmp, September 24
Few pics I found
Few pics I found
by timmp, August 15
Who's Online Now
0 members (), 94 guests, and 11 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 2 of 2 1 2
Joined: Dec 2001
Posts: 2,498
T
Member
Initial verification and testing is mainly intended to rule out installation issues such as faulty connections or pinched wires, to some extent also manufacturing defects (it's rare but cables sometimes do have non-continuous conductors in the middle of a roll, just to give an example). It's typically performed by the contractor who did the work. Commercial premises are also required to be tested periodically, intervals depending on the expected stress on the electrical system. Harsh environments require testing every 6 months in Austria while offices are only to be tested every five years. Switzerland even includes any homes, which have to be tested every ten years, regardless of occupancy status.

Socket testers show that all conductors are connected to the right terminals but they won't usually flag poor (high-impedance) connections. So most regs require low-ohm testing of any protective or bonding conductors before an installation is energised. In periodic inspections, the Rlow test can usually be substituted by a loop impedance (Zs) test.

Ring final circuits obviously make even more continuity testing necessary.

In many countries, owning a multi-function tester (insulation resistance at 500 VDC, Rlow, Zs, PFC/PSC, RCD test) or individual testers covering all the above, is a requirement for operating as an electrical contractor.

Joined: Jul 2002
Posts: 8,443
Likes: 3
Member
Greg,
Could you please define NRTL?
I've not heard of this term before.

This sort of thing is totally foreign to a guy like me. smile

Joined: Jul 2004
Posts: 9,919
Likes: 30
G
Member
NRTL Nationally Recognized Testing Lab. It would be U/L, ETL, TUV etc. They are labs that evaluate and list equipment so we have a standard we can trust. This is an independent test, not self certification like CE. Usually it s destructive testing. They will torture test things until they catch fire and make sure the fire is contained inside the case, grounding holds up, insulation survives and other things along these lines. There is also less destructive testing, like simply making sure the labeling is correct and the load is appropriate for the cord set. One of the guys I heard describing this from the manufacturing side said they kept asking him for more samples because they blew up all he had sent them. This was one of the first listed chlorine generators for a pool and they were making sure it was safe in any failure mode they could think of.


Greg Fretwell
Joined: Jul 2002
Posts: 8,443
Likes: 3
Member
Originally Posted by Texas_Ranger
Initial verification and testing is mainly intended to rule out installation issues such as faulty connections or pinched wires, to some extent also manufacturing defects (it's rare but cables sometimes do have non-continuous conductors in the middle of a roll, just to give an example).


Ragner,
This happens every now and then, I've had a new roll of 6mm² 2 Core and Earth run to an oven or an electrode boiler, it got that bad that I would Megger the cable before it was even pulled through or I would install PVC conduit and pull in single cores.

I do note however that in the UK, the EICR seems to be the port of call for Residential and Commercial periodical electrical testing, what are your or others thoughts on that?

Joined: Jul 2002
Posts: 8,443
Likes: 3
Member
Sorry Greg,
You did actually mention that above.
I would love to work in a place like that.

Joined: Jul 2002
Posts: 8,443
Likes: 3
Member
Hi Simon,
I suppose the real question would be, how much actual wiring experience do you have?

Joined: Jul 2004
Posts: 9,919
Likes: 30
G
Member
Originally Posted by Trumpy
Sorry Greg,
You did actually mention that above.
I would love to work in a place like that.


I agree that would be a great job but it might not be as fun as it sounds. I bet there is hours of watching something, writing down readings and waiting for the fire..

Last edited by gfretwell; 04/04/20 01:16 AM.

Greg Fretwell
Joined: Mar 2020
Posts: 3
S
New Member
Originally Posted by Trumpy
Hi Simon,
I suppose the real question would be, how much actual wiring experience do you have?



Hello,
thanks for the reponses.
I have worked on ships for the most part. Cable pulling, fitting equipment and terminating. No real testing. This course I am currently doing (though on hold for the obvious) is specifically testing. I believe that it would not take long to get into the swing of things after seeing what is expected. I have the hand skills and trying to improve by buying components and fixing them to a board and making/testing the circuits that way. I am not that quick with regs but I would be working as a mate until I get up to speed. My fear is getting lumped with a miserable numpty that wants me to think he is god because he has memorised a few regs and claims to know it all. That can be a real spanner in the works. I have a book coming,

https://www.amazon.co.uk/gp/product/0760353573/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

Black & Decker The Complete Guide to Wiring, Updated 7th Edition: Current with 2017-2020 Electrical Codes

looks ok.
I was thinking about trying to contact a local house bashing spark and ask if I could shadow him for free. I thought an extra pair of hands for free may sway it, in exchange for some hands on experience and a question here or there. Though this worries me also, I don't want to be a slave to someone. If I asked this of you, would you expect me to clear away all your rubbish?
My thoughts are that I offer my current experience/tools/time to help complete him a paid job. In exchange I get experience and help with any questions. Though I try to keep the questions to a minimum, makes you look stupid and naieve apparently. Problem is sometimes I don't get how a person may explain something.
Anyway, thats all for now and a lot too
Thanks for the help
Stay safe!
Simon

Joined: Jul 2002
Posts: 8,443
Likes: 3
Member
Hey Simon,
Sorry for such a late response to your reply.

Electricians amongst themselves are an un-known quantity, you could get people like us here that actually care about the work that they do (that is why they're here) or you could end up with some idiot that is a danger to life and property, by the short-cuts they take and what have you.(Don't get me wrong, I have worked with people like this, they are out there)

Pretty much, if you are good on the tools, any decent Electrician should be able to see that, first off, however I will say this, no-one starts off at the top of the company and if you work with a sole-trader, you are going to be the guy that takes out the trash from a job.

I've done this as an Apprentice, everyone has to do this, it's like a rite of passage, those that complain, don't often last that long, just be aware of it. smile
The best boss/worker you can have, is the one that constantly asks you questions while you work, especially about Regs and the way you do stuff, bearing in mind that they've probably done the same work a thousand times over.

The even better boss/worker is the one that you can ask why this is done like this or so forth, that is real learning + experience.

With respect to that Black & Decker book, I'm not sure that it would be a good way to learn wiring, I could be wrong, but Black & Decker are not intrinsically known for good quality publications.

Take Care, Simon,
If you have any further questions, by all means just ask.

Mike T.
cool

Page 2 of 2 1 2

Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5