Downgrading mcb or adding rcd

[joehat]

For adding an rcd or download grading an mcb for various reasons I've always used a mwc, is this correct or do I need a EIC as this seems alot of work for this?

Sent from my SM-G930F using Tapatalk

 

[telectrix]

as you are altering a circuit and not installing a new circuit, a MWC is correct.. come one joe. take the hat off and scratch the brains. this is basic. :30:

 

[Midwest]

Interesting question, and I'll be advised by someone with more experience Tel.

My C&G 3292 Course book, suggests replacing a protective device in a non like for like manner, would require an EIC not MWC. Similar answer from Elecsa/NIC technical.

So as I understand things mcb for mcb would be MWC. RCBO for MCB would be EIC. Adding RCD to the circuit origin, would be EIC?

 

[joehat]

But also adding sockets to a circuit only requires a mwc yet it's not like for like, it's changing the circuits characteristics if you think about it?

Sent from my SM-G930F using Tapatalk

 

[joehat]

It's the zs reading that you would need to check to comply with the new device no?

Sent from my SM-G930F using Tapatalk

 

[Midwest]

'The replacement device has different characteristics' is the phrase used.

However, my GN3 (A1) shows a model form MWC, replacing an MCB with RCBO, so I'll take advice.

 

[Andy78]

An alteration or addition needs to be tested and certificated in addition to verifying the circuit is suitable for the alteration before work commences.
132.16, 610.4, and 633.1

How you could argue that changing the OCPD for one with different characteristics is not an alteration I'm not sure.

 

[Octopus]

It's the zs reading that you would need to check to comply with the new device no?

Sent from my SM-G930F using Tapatalk

IR
Continuity
Zs
Red times
Farthing
Bonding

To name but a few....

 

[Midwest]

Farting?

 

[7029 dave]

IR
Continuity
Zs
Red times
Farthing
Bonding

To name but a few....

Would that be penny Farthing.?

 

[Deleted member 26818]

Where in BS7671 is there any mention of the terms 'like for like' or 'characteristics of a circuit'?
What exactly is changing the characteristics of a circuit supposed to signify?

When conducting an EICER, I note that the CPC of an RFC is not continuous.
I find the break in the CPC and make good.
Have I not just changed the characteristics of that circuit?

My 60W incandescent light bulb in my bath room burns out.
I replace it with a 7W CFL.
That's not 'like for like' and the characteristics of the circuit have been altered.
Should it be an EIC or MWEIC?

If it stated in the notes for an MWEIC that it may be used for the 'like for like' replacement for an item of equipment, then fine.
However it doesn't, so please stop introducing terms into the Regulations, which do not exist.

 

[Midwest]

Think there's loads of things we should and can't do, that's not in BS7671, (reg 421.1.210 e.g.), that's why 'They' make a fortune out the other publications, that go on to explain the regs and try and make sense of them.

Like the 'Few Good Men' quote, 'Corporal, would you turn to the page in this book (Marine Manual) that says where the mess hall is, please. ........etc etc etc.........'Well, I guess I just followed the crowd at chow time, sir'.

 

[Risteard]

MWEIC [...] However it doesn't, so please stop introducing terms into the Regulations, which do not exist.

"MWEIC" is a term which has never existed in the Regulations. It is an MEIWC.

 

[Deleted member 26818]

"MWEIC" is a term which has never existed in the Regulations. It is an MEIWC.

Who cares?

 

[Midwest]

Who cares?

Wins

 

[Risteard]

Who cares?

Perhaps if you read the rest of what I quoted from your post you would understand the relevance!

 

[GMES]

Who cares?

Wins

Rodney :smilewinkgrin:

 

[Midwest]

Looking at BS7671 (& GN3), it suggests MEIWC (think Ihave my capitals in the right order) 'is intended for alterations or additionsto an installation that do not extend to the provision of a new circuit.Examples include the addition of socket outlets or lighting points to anexisting circuit, the relocation of a light switch etc. The Certificate mayalso be used for the replacement of equipment such as accessories orluminaires, but not for the replacement of distribution boards or similaritems'.

Definition of Accessory 'A device, other than current-using equipment,associated with such equipment or with the wiring of an installation'. No definition of 'similar items'.

So you learned chaps, MCB replaced by RCBO, EIC or MEIWC?

 

[Midwest]

Tumbleweed then?

 

[Deleted member 26818]

Is it a new circuit?
Is it a distribution board or similar?
Is it a single circuit that is being altered, or multiple circuits?