Rules and Guidelines
Want to participate in the discussions? Please read our Community Rules and Guidelines. Need some help? Visit Support and Answers.

  • State Not Answered
  • Locked Locked
  • Replies 38 replies
  • Subscribers 32 subscribers
  • Views 8198 views
  • Users 0 members are here
Options
You may also be interested in
This discussion is locked.
You cannot post a reply to this discussion. If you have a question start a new discussion

EICR C3 mixed manufacturer breakers

Martyn
I know this will have been discussed in the past but we are on Amd 1 of the 18th now so I thought I would renew it.


The Best practice guides list mixed manufacturer breakers in a consumer unit or distribution board as a C3.


As far as I am aware Bs7671 does not have a Reg on it beyond manufacturers instructions and given EICR's are based on this standard perhaps it is justified on that basis.


Most on here will be familiar with the 16kA 'rule' in BSEN61439 Annex ZB or its predecessor BSEN60439 Annex ZA


I avoid C3's like the plague because they give all the wrong signals to a client and clearly by definition are for things which are a breach of the regs, I'm not too keen on the insurance risk of a C3 either.


My question here would be what fault rating can one apply to an enclosure where there are mixed breakers given a manufacturer will only have certified their equipment with their devices?


Enjoy!


Martyn
Parents
  • 0
    Given that a (say) 6kA breaker is guaranteed to break a 6kA fault and be reset.

    During type approval, there is a test that requires the operation of the breaker to be verified again after breaking the full  fault current at least once.

    If operated repeatedly, it must break the fault safely each time after it has been reset, but does not have to reset.- so it has to fail to a safe state where it cannot be reset.

      During all the testing up to that point the presence or absence of a case around it is in is cosmetic, and does not affect the ability to operate.

    It is however allowed to fail at the containment at higher fault currents - and that  is when qualifying the whole assembly comes in, as the outer box may contain the flames and flying bits, so the rating for the breaker in the box, is higher than for the breaker 'bare'. Also at this point the glow wire tests start to matter as when one breaker blows up, you do not want the neighbours catching fire.


    There are a few type approval test reports on the web, that give a flavour of typical results.

    random example 

Reply
  • 0
    Given that a (say) 6kA breaker is guaranteed to break a 6kA fault and be reset.

    During type approval, there is a test that requires the operation of the breaker to be verified again after breaking the full  fault current at least once.

    If operated repeatedly, it must break the fault safely each time after it has been reset, but does not have to reset.- so it has to fail to a safe state where it cannot be reset.

      During all the testing up to that point the presence or absence of a case around it is in is cosmetic, and does not affect the ability to operate.

    It is however allowed to fail at the containment at higher fault currents - and that  is when qualifying the whole assembly comes in, as the outer box may contain the flames and flying bits, so the rating for the breaker in the box, is higher than for the breaker 'bare'. Also at this point the glow wire tests start to matter as when one breaker blows up, you do not want the neighbours catching fire.


    There are a few type approval test reports on the web, that give a flavour of typical results.

    random example 

Children
No Data

Join us to get the best from IET EngX.

Joining EngX lets you personalise your experience so you stay up to date on the topics that interest you, plus you’ll be able to make connections who are looking to collaborate, exchange ideas and more.

Join us Not now

Community Rules & Guidelines