Live Or Dead Testing - A Question For Members

[apprentice87]

Yes, we all know that an RCD is USUALLY used as additional protection. But that still does not mean that it cannot be used on its OWN to provide ADS in a case where Zs is too high to use an OCPD in the usual way. Obviously we still need to provide overcurrent protection too... If you were not allowed to use an RCD to provide ADS, then what you going to do in a TT system??? How would you provide for ADS then?? The ONLY way you could normally provide ADS would be by using an RCD..john

 

[says-les]

I found this at

http://www.esc.org.uk/industry/industry-guidance/industry-guidance-on-the-wiring-regulations/3-places-of-work-new-installations/

Q3.5

If an RCD is used to achieve automatic disconnection within the prescribed time, is the supplementary bonding called for in 411.3.2.6 still required?

No. An RCD is a valid way of complying with automatic disconnection requirements.

Regulation number(s)

411.3.2.2

411.3.2.3

411.3.2.4

411.4.4

411.4.9

 

[says-les]

Also found this at

http://www.talk.electricianforum.co.uk/topic/9225-direct-measurement-of-zs/

I wish I had found it before posting this original question. However it has been a good debate/discussion and I hope everyone is satisfied as to the correct train of thought.

Having said all this, as a boy I thought that live earth loop testing was the only important test, using the flying lead. nowadays things have moved on. It is only in the event of an accident that your methodology is investigated by a lawyer that criminal proceedings may be imposed (a fine). Both you AND your employer can be fined, the employer for not ensuring safe practise training is in place. It is not about how good a spark you are at testing live. Stop doing it for YOUR sake!!

 

[Technician]

Methodology....I hate that word.

Dreamed up by men in suits to

confuse and obfuscate discussion

so that they can grab the upper

hand while the other side experience

a temporary loss of reason.

Importantly...another one.

 

[says-les]

technician, sory the way they prefer instead, then, sorry.

cheers mate

 

[Technician]

No worries Les;  I just hate the abuse of

words and their appropriation by pressure

groups to further their causes.

When I write for any reason, I aim to be

ABSOLUTELY clear in my expression, and

I will confirm one way or the other if any

word is being used correctly.