Additional protection by means of RCDs

[Danny Huht]

Hi,

I'm an electrical apprentice and was just wondering if anyone could explain additional protection using RCD's?

Thanks

 

[Pete999]

Hi,

I'm an electrical apprentice and was just wondering if anyone could explain additional protection using RCD's?

Thanks

Do you have a copy of BS7671 the big yellow book?
Reg 411.3.3 Additional protection

 

[Danny Huht]

Do you have a copy of BS7671 the big yellow book?
Reg 411.3.3 Additional protection

I do at college but not at this moment in time

 

[Danny Huht]

Do you have a copy of BS7671 the big yellow book?
Reg 411.3.3 Additional protection

Thanks for the help

 

[Pete999]

Thanks for the help

Do you have a copy?

 

[Spoon]

Hi mate. Have you tried Google? Lots of knowledge there.
Is there something specific you would like to know and that is why your are asking the forum?

 

[Pete999]

Hi mate. Have you tried Google? Lots of knowledge there.
Is there something specific you would like to know and that is why your are asking the forum?

I think the OP is/was just trying to understand the meaning, I could be wrong but that's my take on the question.

 

[Pete999]

I do at college but not at this moment in time

Worth keeping it at Home for times just like this one

 

[Risteard]

Worth keeping it at Home for times just like this one

I don't think he means he has his own personal copy. He is an Apprentice, and I take it he means that he has access to a copy at the training centre when he needs it but doesn't personally own a copy.

 

[Pete999]

Hi,

I'm an electrical apprentice and was just wondering if anyone could explain additional protection using RCD's?

Thanks

Danny try and get access to the Trainee area, not sure what the criteria is, plenty of knowledgeable people/Mentors there only to willing to help, plus you won't get any mickey taking, however daft the question may seen to you, give it a try.

 

[Pete999]

I don't think he means he has his own personal copy. He is an Apprentice, and I take it he means that he has access to a copy at the training centre when he needs it but doesn't personally own a copy.

Yes mate you probably are correct, from catching from some of the replies, that's how I read the situation, I don't use my copy much now I am retired, but reluctant to give it away as I like to have a quite read sometimes, just to exercise my brain once in a while, Red Wine permitting that is.

 

[Pete999]

Thanks for the help

Any time Dan

 

[Spoon]

Just a bit of info from the regs.

411.3.3 Additional protection


In a.c. systems, additional protection by means of an RCD in accordance with Regulation 415.1 shall be provided for:

(i) socket-outlets with a rated current not exceeding 20 A, and |

(ii) mobile equipment with a current rating not exceeding 32 A for use outdoors.

An exception to (i) is permitted: |

(a) where, other than for an installation in a dwelling, a documented risk assessment determines that the RCD

protection is not necessary, or

(b) for a specific labelled or otherwise suitably identified socket-outlet provided for connection of a particular |

item of equipment.

NOTE 1: See also Regulations 314.1(iv) and 531.2.4 concerning the avoidance of unwanted tripping.

NOTE 2: The requirements of Regulation 411.3.3 do not apply to FELV systems according to Regulation 411.7 or reduced low


voltage systems according to Regulation 411.8.

NOTE 3: See Appendix 2, item 10 in respect of risk assessment.



415.1 Additional protection: Residual current devices (RCDs)


415.1.1 The use of RCDs with a rated residual operating current (lAn) not exceeding 30 mA and an operating

time not exceeding 40 ms at a residual current of 5 lAn is recognized in a.c. systems as additional protection in the


event of failure of the provision for basic protection and/or the provision for fault protection or carelessness by users.

415.1.2 The use of RCDs is not recognized as a sole means of protection and does not obviate the need to


apply one of the protective measures specified in Sections 411 to 414.

 

[Danny Huht]

Just a bit of info from the regs.

411.3.3 Additional protection


In a.c. systems, additional protection by means of an RCD in accordance with Regulation 415.1 shall be provided for:

(i) socket-outlets with a rated current not exceeding 20 A, and |

(ii) mobile equipment with a current rating not exceeding 32 A for use outdoors.

An exception to (i) is permitted: |

(a) where, other than for an installation in a dwelling, a documented risk assessment determines that the RCD

protection is not necessary, or

(b) for a specific labelled or otherwise suitably identified socket-outlet provided for connection of a particular |

item of equipment.

NOTE 1: See also Regulations 314.1(iv) and 531.2.4 concerning the avoidance of unwanted tripping.

NOTE 2: The requirements of Regulation 411.3.3 do not apply to FELV systems according to Regulation 411.7 or reduced low


voltage systems according to Regulation 411.8.

NOTE 3: See Appendix 2, item 10 in respect of risk assessment.



415.1 Additional protection: Residual current devices (RCDs)


415.1.1 The use of RCDs with a rated residual operating current (lAn) not exceeding 30 mA and an operating

time not exceeding 40 ms at a residual current of 5 lAn is recognized in a.c. systems as additional protection in the


event of failure of the provision for basic protection and/or the provision for fault protection or carelessness by users.

415.1.2 The use of RCDs is not recognized as a sole means of protection and does not obviate the need to


apply one of the protective measures specified in Sections 411 to 414.

Thanks very much, should help a lot mate

 

[Danny Huht]

Danny try and get access to the Trainee area, not sure what the criteria is, plenty of knowledgeable people/Mentors there only to willing to help, plus you won't get any mickey taking, however daft the question may seen to you, give it a try.

Will do matey, cheers

 

[telectrix]

regs.aside, the actual purpose of a RCD is to protect against accidental contact ( of a human or animal's body part ) with a live part which for some reason ( e.g. a cut cable ) has become exposed to touch; as different from fault protection whereby a normally non-live part has become live through a fault ( e.g. a live conductor touching or shorting to a metal enclosure. this latter is protected by your fuse/MCB.

 

[Midwest]

Just a bit of info from the regs.

411.3.3 Additional protection
.

Hope that wasn't a cut & paste, the IET police are everywhere

 

[Spoon]

Hope that wasn't a cut & paste, the IET police are everywhere

Yes it was. Have to see the regs as to how many characters I can 'cut & paste' before I get my hands smacked.

 

[telectrix]

here's a couple of characters you can copy and paste. in fact, they need a good pasting.

 

[Midwest]

here's a couple of characters you can copy and paste. in fact, they need a good pasting.

Is that you on the left? Looks like Pete on the right