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Mixed manufacturer devices in din rail enclosure.What code?

hertzal123
Have found out a catering company,I deal with fit servery counters in supermarkets and use Schnieder din rail

enclosures,3 pole main switch, 3 phase bus bar,and a different brand of mcb/rcbo.I assume this is wrong and wondered

what code it could attract on a condition report?If I constucted the unit using all Schnieder parts,would the unit still

have to be type tested by others?

                                              Regards,

                                                         Hz
  • 0
    As a point of interest, has this type of case ever been tested in the Law courts?

    The manufacterers state you can't mix different companies components together in the same enclosure although You might not be able to avoid this when using SPDs and AFDDs with MCBs etc

    The BS7671 book of guidance states you should follow manufacturer's guidelines.

    It strikes me that there is no legal president that has been established for this type of situation.

    Legh
  • 0
    Legh Richardson:


    The manufacterers state you can't mix different companies components together in the same enclosure although You might not be able to avoid this when using SPDs and AFDDs with MCBs etc

     


    Well, BS 7671 says you can use components from different manufacturers, BUT you become responsible for the if the use of a particular component deviates from the original assembly manufacturer's instructions (Note 2 to Regulation 536.4.203).


    Whilst there is no legal precedent that I'm aware of, the legislation for the relevant Directives does really lead you to that conclusion.


    In this particular case, a DIN rail is only a mounting standard, not a standard that invites you to make whatever modifications you like to the assembly that includes it.


    Where does this leave the empty "adaptable enclosure" with a DIN rail? Well, when you assemble a variety of products from different manufacturers into that kind of empty enclosure (and I'm not talking about a consumer unit here, where you're assembling in accordance with manufacturer's instructions), you become the assembly manufacturer. The assembly itself is not covered by BS 7671, see Regulation 113.1 (second sentence). So, if you're buying DIN rail products, if you want to avoid being an "assembly manufacturer", use the enclosure from the relevant range of products from the DIN rail product manufacturer, in accordance with the manufacturer's instructions.


  • 0
    Whilst there is no doubting the above comments, it appears that you are looking at this from a periodic inspection perspective. Thus compliance with BS7671 or any other standard is not necessarily an issue. If you determine that the assembly is unsafe or could become unsafe in some way then a code is appropriate. If, on the other hand, you do not see any obvious safety issue, depending on the purpose of your inspection, you might either call attention to the issue or simply disregard it.
  • 0
    If the folk doing the mix and match are happy to be the 'manufacturer' and have designed it with sensible current ratings and so forth, then they are fine. They have no comeback on the component makers if their sums are wrong and it all melts however.



    What hazards and failure modes have they overlooked?
  • 0
    mapj1:

    If the folk doing the mix and match are happy to be the 'manufacturer' and have designed it with sensible current ratings and so forth, then they are fine. They have no comeback on the component makers if their sums are wrong and it all melts however.



    What hazards and failure modes have they overlooked?


    Do,nt know,but they were suggesting I copy their design,which I,m not prepared to do.

                                                                                                               Regards,Hz


  • 0
    I had similar thoughts when I was under the counter in a fish and chip shop, there’s a very tidy box containing B2 MCBs and other similar devices for the frying range, but not all from the same manufacturer. I whimped out and excluded it as an appliance that is beyond the remit of the EICR, because the frying range is gas fired with an interlocked extraction system requiring training and registration that I do not have to work on it and to inspect.


    I have learnt to pick my battles, like when I did the PAT in a local church and the warden said the organ builders had requested that I didn’t fiddle with the organ, I pointed out it was SELV and said I would test to the transformer and let it go after that, which seemed to satisfy everyone.


    Are you going beyond the requirements of a fixed installation EICR and moving into machine and appliance regulations?


    Andy Betteridge 


  • 0
    I don’t think many electricians realise you can get MCBs rated at half an amp, when I see such items in a box attached to an appliance I stop there and declare it beyond the remit of the EICR, so won’t be trying to attach EICR codes, unless there’s a clear and obvious issue.


    Going back to the original post the major issue of devices from different manufacturers on the same rails is always going to be do they sit correctly on the pins?

    https://www.se.com/ww/en/product/A9N61500/miniature-circuit-breaker---c60h---1-pole---0.5-a---c-curve/
  • 0
    Sparkingchip:


    Are you going beyond the requirements of a fixed installation EICR and moving into machine and appliance regulations?


    Andy Betteridge 


     


    This is a great question, because when you talk to some people in the industry about the extent of an EICR (or even initial verification), they believe that you will, say, do an earth continuity test to an appliance connected to a fixed connection unit - yet the appliance, and where applicable its pre-fitted connecting cable, are outside the scope of BS 7671.


    Regardless of the technicalities in standards regarding the rights and wrongs of this belief, in my experience those carrying out initial verification and EICRs go up to the point of connection of an appliance or machinery, and no further - the usual exception being lighting where the fixed wiring is brought into the luminaire.


    Why is this a good thing to have a discussion about?


    Well, the person ordering an EICR might be under the impression that they've had the earthing of their fixed appliances checked ... when in fact it's been omitted, often with very good reason ... for example with appliances having a mix of means of protection against electric shock:



    • just because you can't get earth continuity to an accessible metal part doesn't mean it's a "fail", because that part might not be an exposed-conductive-part in that particular appliance, and without dismantling it you can't tell

    • on the other hand, saying "pass" because you got a reading at one accessible conductive part doesn't mean the whole appliance is correctly earthed, and you'd be implying the appliance was OK when it wasn't !



    So, as an example, what happens when the landlord has his regular check, but there's a problem with the protective earthing in an electric wall-mounted radiator or towel-rail, and someone gets a shock?


  • 0
    I did an EICR yesterday for a house purchaser, the vendor was at home and enquired what the long green wire is for, as in my wander lead. I explained that in a house like his with metal faced fittings and lots of metal light fittings it is the quickest and easiest way of ensuring things that need to be earthed are.


    The range cooker was checked by dabbing the probe onto the screw of the wall mounted switch and the appliance itself, the shower had to have its cover removed. 


    The kitchen socket ring did not have continuity on the CPC, the wander lead narrowed the search to a couple of fittings with the CPC connected at one end in the CU, the last one to give a reading and the first that didn’t.


    I am a firm believer that all EICRs should be carried out using a long wander lead to check earth continuities, allowing towel rails and the like to be easily checked. I know the frying range in the chip shop is earthed, but didn’t delve to deeply, the cable to it is adequate and so is the protection to that cable, also it is adequately earthed. But I didn’t check the internal wiring to the heat lamps that keep the fish, sausages, savoie's and pies warm as that really has to be beyond an EICR.


    Hertzal needs to have a word with Schneider, I can’t see an issue in making up a board using their components, but some devices for controlling catering equipment may not be available from them if it’s particularly specialist or supplied as a kit as part of an interlocking system or the like.


    As an aside, I stopped at a roadside cafe in a cabin in a lay-by on Paul Sykrmes’ patch last year and whilst I was waiting for my bacon butty to be cooked they asked if I could do them an EICR for their licence, I declined as it was a long way from home and they should be able to get someone local to do it at a much more reasonable price, he guy laughed and said there’s only three people in Wales who will do LPG gas safety checks for mobile catering units in Wales and he was struggling to find an electrician. At this point you realise that there’s not many people actually doing work on mobile catering and other catering equipment. Here in Worcester there was one guy who was gas and electric registered, he did all the frying ranges in the local fish and chip shops, when he died at a young age they were all struggling to get certification for their equipment.


     Andy Betteridge 


  • 0
    Sparkingchip:

    I did an EICR yesterday for a house purchaser, the vendor was at home and enquired what the long green wire is for, as in my wander lead. I explained that in a house like his with metal faced fittings and lots of metal light fittings it is the quickest and easiest way of ensuring things that need to be earthed are.


    The range cooker was checked by dabbing the probe onto the screw of the wall mounted switch and the appliance itself, the shower had to have its cover removed. 



    So, you're happy to say that the range cooker has all parts earthed that are supposed to be?


    Also, did you check to the shower termination point, or all parts of the shower that are earthed (e.g. element plate and water tank if that was metal)? Thankfully, showers are easier than more complex appliances.



    Just to be very clear, I'm not criticising Andy here, just thinking about the process and limitations.

     


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