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Topic Title: Codes and How to Rate Deviations
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Created On: 05 April 2013 01:41 PM
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 05 April 2013 01:41 PM
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Bluesmeister

Posts: 14
Joined: 05 April 2013

Having read a few posts it would seem that there is still some confusion of the deviation codes C1, C2, and C3, and how to apply them to various deviations that are recorded on a EICR.

I thought that the new codes were introduced to make things more black and white, but has it?.



A 16th or even 15th Edition consumer unit may justify no code at all if installed correctly, or you may say coded a C3.

I don't know about you but I miss the old 1, 2, 3, & 4. codes.

Perhaps I am just too old.
 05 April 2013 07:42 PM
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IQelectrical

Posts: 2
Joined: 28 May 2012

You wouldn't allocate a code to 'a consumer unit' unless there was a specific defect relating to it-do you mean lack of RCD protection if required?
If that's the case then each defect would be coded accordingly ie.

No RCD protection to socket outlets
No RCD protection to cables buried in walls....
No RCD protection to bathroom circuits

Have a read of this guide Link removed/fileadmi...ticeGuide4-Locked.pdf

If the link is removed, go to the Electrical Safety Council website and find the Best Practice Guide to EICR.

-------------------------
Fixed Wire Testing
Link removed
 05 April 2013 09:48 PM
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Martynduerden

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Joined: 13 July 2008

Originally posted by: IQelectrical

Have a read of this guide ESC BPG



Link

-------------------------
Regards

Martyn.

Only a mediocre person is always at their best



www.electrical contractors uk.com
 07 April 2013 12:54 AM
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jimmyoneball

Posts: 23
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What I normally do for old non RCD CCUs is C3 for cables in the wall/socket outlets for normal persons and then C2 for socket outlets likely to be used outdoors (thats in the ESC guidance). Also if resistance from bathroom light cpc to water pipes exeed 0.05 Ohms without RCD then thats a C2 as well.

It may be worth considering that the old BS3036 sometimes have a maximum PFC of 1.0kA so if that is exceeded it is arguably a C2 which would result in an unsatisfactory - then give it 6 months for remedials.

In short there are a lot of grounds for failing the MoT. Hope this helps
 07 April 2013 06:43 PM
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jcm256

Posts: 1792
Joined: 01 April 2006

However, jimmyoneball BS 3036 fuses have been around as long as electricity. A code C2 "potentially dangerous", would indicate that millions of homes had something dangerous lurking under the stairs or the box in the hall. As far as I know the current edition of BS7671 still allows re-wire able fuses. I know what you are saying the rewireable fuse and or "MCB" takes longer to operate, resulting in the production of greater heat energy and electro-magnetic stress, than say a sooner to operate HRC fuse but would you code an MCB. By all means a code 1 or 2 if a fuse or fuses be fitted with inappropriate wire links, but a domestic don't you take that little card of fuse-wire out of the toolbox and fit the appropriate size of fuse element in the fuse to exclude all the hassle.
Please reconsider your post otherwise; I will be glancing at my nice shiny Mem Memera consumer (unit mixture of rewireable and cartridge to BS 1361) every time I pass.

Thanks
jcm
 07 April 2013 11:51 PM
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alancapon

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Originally posted by: jimmyoneball
. . . It may be worth considering that the old BS3036 sometimes have a maximum PFC of 1.0kA so if that is exceeded it is arguably a C2 which would result in an unsatisfactory . . .

Really? You will find that as long as the CU complies with annexe ZA of BS EN 60439-3 it will have a conditional rating of 16kA breaking capacity. In my opinion, giving these CUs a code C2 is one of the most widely used myths used to justify a rewire.

Regards,

Alan.
 08 April 2013 12:49 AM
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Martynduerden

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Originally posted by: alancapon

Originally posted by: jimmyoneball

. . . It may be worth considering that the old BS3036 sometimes have a maximum PFC of 1.0kA so if that is exceeded it is arguably a C2 which would result in an unsatisfactory . . .


Really? You will find that as long as the CU complies with annexe ZA of BS EN 60439-3 it will have a conditional rating of 16kA breaking capacity. In my opinion, giving these CUs a code C2 is one of the most widely used myths used to justify a rewire.

Regards,

Alan.


Totally agreed, However, They are not great and would generally indicate an aged installation with a high quantity of genuine faults.

The installation having 3036 fuses does not itself indicate faults but you don't come across many without significant faults.

Think de-rating factors specific for the fuse type.
1mm cables
No cpc's
No water & gas bonding
loads of ill conceived mods
littered with down lights

The list is endless.

It really winds me up when people justify rewires solely on the back of these fuses, it also winds me up when Pirs say everything is ok on a 1960s install just because the IR checks out.

I am generally of the opinion that an installation has a lifespan of 30-40years maximum, there are exceptions to this such as commercial premises under a maintenance program...but then the majority of them never sees 40 without modification / replacement parts etc.

-------------------------
Regards

Martyn.

Only a mediocre person is always at their best



www.electrical contractors uk.com
 08 April 2013 12:37 PM
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marclambert

Posts: 304
Joined: 23 June 2010

Just beware the guides.
The only advice anyone can really give on one of these "what code would you give" questions is this....
You decide, you're there, you're the competant person (aren't you?), use your skill and experience.
Many pages of forums have been wasted on the arguements over who would give what code to what.
Rant over.
cheers
 08 April 2013 12:50 PM
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jsa986

Posts: 472
Joined: 08 February 2011

Very good point marc

Regarding the old Wirlex fuse boards that people seem to rush to defend for some reason. Lets bear in mind these often have an exposed open back, & are made partly of wood. Further to that they are inconvenient when they blow (if users haven't put silver foil there) and were never designed with todays demands on the circuitry. Also have you tried to get a 16mm earth in the earth bar in one of them! (I accept that 60 main fuse should only have 16mm tails with 10mm main earth argument) however that just make the point even more

Im sure theres plenty of regs that could be interpreted as a way to ditch these things. Enclosure for electrical equipment is inadequate.? Fire resistance etc?

-------------------------
www.icertifi.co.uk
Electrical & Gas Certificates on iPhone & iPad

Edited: 08 April 2013 at 01:00 PM by jsa986
 09 April 2013 02:01 PM
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AJJewsbury

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nclosure for electrical equipment is inadequate.? Fire resistance etc?

probably just as good, if not better, than their plastic replacements - judging by reports (and pictures) from some contributors.
- Andy.
 09 April 2013 03:06 PM
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Jaymack

Posts: 4479
Joined: 07 April 2004

Originally posted by: jsa986
Also have you tried to get a 16mm earth in the earth bar in one of them!
Not if you trim the twisted end I found, and just enter the cable. I had drilled out an old Wylex earthing bar as a replacement, but didn't need it. I had to uprate, when the supplier was advised of a high Ze reading on a TNC-S supply in a fish shop, they were there the next day to change to PME. Also, there was no main bonding to the incoming water pipe!

The upgrade was necessary, due to the test results when the owner just wanted a socket spurred, in an office! The Zs for the FRC was OTT.

The same job where the owner also wanted a twin socket outlet replaced, due to burnt plastic at the socket pins. He was running a cod roe water boiler of 4kW on a 13A socket every day, for many hours during the season! This socket also had one self tapping, fixing screw to the front plate. "When did you last have an electrician on the premises?" His reply - "I don't remember, but it was many years ago" ........ There was a manufacturer's date label from 9 months before, stuck behind the socket plate! Funny that, but I did tell him of the strange finding.

Regards
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