hi,this is my first post.

[SPECIAL LOCATION]

Yes as ian says, the BRB is very much open to interpretation... :|

And at the end of the day, it is the person who is doing the work who will have to make the final decisions.

Proving that ALL essential safety checks have been done and to ensure the safety of any alterations.

IMHO its about being able to justify your choice of documentation.

This is where it is good to be able to debate the various pro's & con's and interpretations with other qualified & competent persons, on forums such as this! Applaud Smiley (without having any hissy fit scraps!!! :^OGuiness Drink)

I guess the bottom line has to be.. "If you are in any doubt do a full EIC!" your bottom end is well and truly covered then.

Also the table the NIC book has an element of interpretation..

Item 'H' refers to replacing items of switchgear on a 'NON like for like basis'..

I tend to read this as if you are upgrading the fuse rating or changing the characteristics (re Zs!)..

such as wired 30A to 32A MCB, wired 15A to 16A MCB etc..

or upgrading light circuit from 6A to 10A maybe?

I understand 'like-for-like' to mean an item with equivalent ratings / capacities,

NOT just a direct identical manufactures make - model etc..

e.g. Like 4 Like?

A Gainsborough 8.0K shower replaced with a Triton 8.0k shower is 'like 4 like', but NOT if replaced with a 9.0k shower?

A 20A 3036 replaced with a 20A 60898 is NOT 'like 4 like' as although they have identical current ratings,

they have different max Zs values in the tables on pages 48/49 of BRB..

But when swapping a 6A type B MCB BSEN60898

and a combined RCBO with 6A type B BSEN61009-1, overload protection.

Both have the same max Zs, (7.67ohm), from the table on page 49.

the time current characteristics ref with reference to PFC are on the same graph... PAGE 249.

So to my interpretation the overload protection & disconnection time characteristics are 'Like-4-Like',

all we have done is just added shock protection as well???

If I had fitted a standalone RCD next the CU and diverted the circuit through that I would also have just done a MWC.

As said the NIC guidance is just as much open to interpretation as the BRB?

you just need to be able to justify your case and reasoning.

:|

 

[SPECIAL LOCATION]

The ones with no Logo I hope

phttt! :_|

The "green forms" are none logo'ed!

Logo'ed ones are pretty colours... reds & purples....Blushing

:|

 

[SPECIAL LOCATION]

im not with nic eic yet but am planning to go with them in a few weeks so have been using there green forms to familiarise myself with them.

Thats good...

you can use them to show the inspector how you would fill out the documentation...

and it would add the extra bit of boot-licking grovel factor to be using NIC green forms rater than just a-n-other free download forms!

 

[ianmacd]

I asked this question of ELECSA and they said an EIC would be required not just a MWC. I would imagine NICEIC will have a similar answer too.

Ian.

 

[monkey5]

ok thanks ian,ill take that on board,might just give them a call see if there'll tell me coz want to doing it right,

 

[tom1]

i would like to use minor work but in the nic eic hand book it states

replacement of individual item of switchgear inc control switch or protective device not in like for like manner eg replacement device has diff characteristics. minor must not be used.

 

[kme]

Fair enough, but the overcurrent characteristic has NOT changed (unless the RCBo is of a "C" curve design.

I must admit, I have previously removed a wylex 3036, replaced with a plug-in MCB, and issued MWC. Would continue to do so too, as I believe EIC is somewhat overkill for such a procedure. You`ve left the installation safer than it was; no matter what else is or isn`t done.

While preparing to duck behind my anti-missile shield; the "max Zs" question appears.

Now I ALWAYS use the 80% figure on the cert; for 2 reasons:

1. That figure is lower, as it allows for increased conductor temp., and therefore is not only a better figure for compliance; but also provides a "safety margin", i.e. if your Zs on "cold" cables passes the 80% figure; then, by definition, you`ve passed the 100% figure, which is based on "hot" cables.

2. For those who use NICEIC forms, if you open the front cover of any of the following:

IMN2, DPN4, DCN5, IPN2, ICN2

You will find a table of *****TABULATED***** values, along with a description of use. This clearly states that tabulated values should be used.

Sorry guys - but you`re wrong about 100%. Use 80% instead.

Trailer boy - you should know better

 

[SPECIAL LOCATION]

Fair enough, but the overcurrent characteristic has NOT changed (unless the RCBo is of a "C" curve design.I must admit, I have previously removed a wylex 3036, replaced with a plug-in MCB, and issued MWC. Would continue to do so too, as I believe EIC is somewhat overkill for such a procedure. You`ve left the installation safer than it was; no matter what else is or isn`t done.

Concur, can easily put sufficient info on MWC to verify your alteration is safe without choppin down another rain forest's worth of paper!

While preparing to duck behind my anti-missile shield; the "max Zs" question appears.

Now I ALWAYS use the 80% figure on the cert; for 2 reasons:

1. That figure is lower, as it allows for increased conductor temp., and therefore is not only a better figure for compliance; but also provides a "safety margin", i.e. if your Zs on "cold" cables passes the 80% figure; then, by definition, you`ve passed the 100% figure, which is based on "hot" cables.

2. For those who use NICEIC forms, if you open the front cover of any of the following:

IMN2, DPN4, DCN5, IPN2, ICN2

You will find a table of *****TABULATED***** values, along with a description of use. This clearly states that tabulated values should be used.

erm? no it doesn't

it is generally accepted guidance that your measured values should be below these 80% values, BUT (a) they don't have to be & (B) it doesn't say write this 80% value in the column!

Sorry guys - but you`re wrong about 100%. Use 80% instead.

Trailer boy - you should know better

phtt! :| You been getting too much sun on them exotic holidays you keep going on bud!

sapping all your knowledge there... think you ought to invest in a caravan! ]

In this particular occasion I shall have to disagree with you...

& IMHO I do know better BlushingO)

It IS the 100% NOT the 80% wot you wright on the cert.

Reasons:-

1/

Last paragraph of the "front cover of any of the following:

IMN2, DPN4, DCN5, IPN2, ICN2" reads thus...

Where the measured value of the earth loop impedance exceeds the relevant tabulated value below, further investigation will be necessary to evaluate the particular circumstances to confirm that compliance with BS7671 has been achieved.

e.g. In certain situations compliance CAN still be achieved with measured values greater then the 80% tabulated values. so by definition the Tabulated values are NOT the maximum permitted for compliance, and in this situation your certificate would have a measured value exceeding the max allowed!

2/

The column heading on page 3 of the cert says.

"Maximum Zs permitted by BS7671" which IS what tables 41.x pages 48 49 are!

3/

The NICEIC book inspection testing & certification, Chapter talks about how to fill in your schedule of results etc..

circuit detail's the bullet point for

Maximum Zs permitted by BS7671(ohm) states in its opening sentence...

This column should record the maximum permitted values of Zs, by reference to the limiting earth loop impedance values given in chapter 41 of BS7671, NOT to other tabulated 'corrected' values used for comparison with measured values obtained at ambient temperature.

4/

A couple of years back I was picked up on my annual assessment for writing the tabulated vales on my cert! Captain "NicEic" pointed out the column IS max, Not tabulated... (they do like to find one or to recommendations to give to you during each assessment) he pointed me to page 139 of my inspection book! and suggested if in any doubt about what to write in any of the boxes.. double check in the book, as it covers pretty well most of them!!

So I will be continuing to write the 100% not the 80% in the max permissible column!

; )Guiness Drink:x

 

[Lee321]

agree SL

 

[SPECIAL LOCATION]

agree SL

Guiness Drink:x

And I agree as well lostit!

 

[kme]

OOOOh! Blushing:coat

Told you I would be behind my anti-attack thingy, that Steptoe left for me. :x ]

In that case, I shall retract my statement, in its entirety (except for the bit about knowing better - that is still open to interpretation IMHO )

O) ] :x

 

[SPECIAL LOCATION]

:YGuiness Drink:YGuiness Drink:_|

OOOOh! Blushing:coatTold you I would be behind my anti-attack thingy, that Steptoe left for me. :x ]

In that case, I shall retract my statement, in its entirety (except for the bit about knowing better - that is still open to interpretation IMHO )

O) ] :x

You are a gent sir!Applaud Smiley

BUT..

it would have been more fun if we could have had a beer fight to sort it!

Guiness Drink:Y

 

[kme]

You want to throw red wine around - be my guest. Admin`ll have a hissy fit - you can`t get the stains out. :x ]

But we are NOT chucking KME`s Guinness at each other - an offence such as that will have you hung, drawn, quartered, slaughtered & the remnants doused in petrol & lit. The ashes would then be stamped on & drowned in water. :x

YOU HAVE BEEN WARNED ! X(