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Which LVD harmonised standard[s]?

Udtwmc
Hi all,


I'm new to designing electrical equipment for 'test rigs', equipment I wouldn't define as machinery. On these rigs there may be measurement instrumentation, a low voltage control panel with a PLC, switchgear and control gear along with emergency stop circuits, The plant may have pipelines containing non-hazordous liquids/gases and control valves and pumps, but no external moving parts. 


So i'd like to know if there is a definitive LVD harmonised standard that I can buy with the aim of CE marking this equipment (obviously there's the EMC directive to condider but i'm just thinking in terms of the LVD as I don't beleive the Machinery Directive is relevant here, but maybe i'm wrong). Can for example EN60947-5-1 cover the LVD or is there a host of other standards I've not considered?


Also, where can the IET wiring regs BS7671 be of use for the purpose of CE marking electrical equipment?


Thanks in advance
  • 0
    Starting with your final question and working backwards....

    BS7671 can't be used for CE marking electrical equipment as it is a British Standard, not a European one. Only European Standards (EN xxxxx / BS EN xxxxx), Cenelec Harmonised Documents (HD xxxxx) or International Standards (e.g. IEC) can be used for that.

    If you CE mark the equipment it is a declaration that the equipment complies with all the relevant standards - you can't pick and choose. It doesn't even limit it to the LVD but means it must comply with any relevant directive (including the Machinery Directive, EMC, Pressure Equipment Directive, etc.). Of course if you can show that a particular directive is not applicable then that is fine. However beware of assuming a directive does not apply as it is best to read the exclusions rather than be caught out. The directives are normally available to download so it should be easy to check.

    If you want to know what standards are called up by the LVD I would suggest the following:

     https://ec.europa.eu/growth/single-market/european-standards/harmonised-standards/low-voltage_en .

    I know it is a daunting list but you can probably ignore a lot of them as many are only applicable to particular equipment.


    Alasdair
  • 0
    Agree, it can easily become a vertitable can of worms, and there are folk who make a full time living advising on which standards apply to what kit. The fact the standards are very pricey if all that is needed is a quick look to decide it is not the one you want after all tends to discourage the smaller outfit from going it alone. Unless it is very simple, you may find you need to set some effort aside for 3rd party consultancy.

  • Former Community Member
    0 Former Community Member
    I have actually been involved in CE marking a system, similar to that which is described.

    It had pumps, which have moving parts, so regardless of whether they are exposed or not, the machinery directive will apply.


    As Mike suggests you may need external assistance and there are people out there who make a living out of it, thanks Mike, I pretty much do these days! ?


    The other posts have provided good advice.

    However, harmonised standards are not compulsory, they are voluntary, the trouble is if you don't use them, and something goes wrong, you will have to justify what you did was as safe, or safer then following the harmonised standards, good luck with that, the administrative burden alone outweighs any benefit from not having and following the harmonised standards to be able to claim a presumption of conformity.
  • 0

    Paul Skyrme:

    However, harmonised standards are not compulsory.....and following the harmonised standards to be able to claim a presumption of conformity.




    Very true. The Directives are the legal document and are what you must comply with. The EU then request CEN or CENELEC to produce a standard in support of the directive (rather in the manner of Al Capone requesting a favour....and having been a CENELEC TC Chairman I know what I am talking about). Any such standards, and any other relevant European or worldwide International Standards will then be cited as supporting standards and meeting those standards will be taken as 'presumed compliance' with the Directive. However if you are able to meet the requirements of the Directive by other means that is also acceptable, but as Paul says, you may have to justify your claim of compliance.


    As an extreme example I know of an instance where a standard had been prepared by ISO and was used in support of a particular Directive, but it was an electrical standard (and therefore not within the remit if ISO, but that is a different issue) and the relevant IEC committee did not consider it ensured safety. If somebody had been injured or killed by the equipment covered and questions had been asked, if it met the standard would have been considered as meeting the Directive and no action would be taken but if it did not meet the standard, then even if it was safer than the standard would have provided the manufacturer could be prosecuted. An extreme example, I know, and fortunately not something that has happened as far as I am aware.  I just present this example to support Paul's last statement.

  • Former Community Member
    0 Former Community Member
    If I'm understanding you correctly, you will be building a complete machine, so you will be required to prove that it meets the relevant machine specific Type C standard (if there is one), this will generally have a risk assessment for the machine you wish to build and guidance of the safety requirements.  Also type B standards eg. IEC 60204 (Electrical Equipment of Machines), the best way to describe these types of standards or how to construct/build standards and always ISO 12100.

    PILZ UK have done some excellent Webinars on CE, Machinery Directives, and other standards which are well worth catching if this is the type of work you undertake.
  • 0

    Thank you all for your advice and the link to LVD standards library - well at least there’s not that many to go at then :) and I’ll definitely check out those CE marking webinars. Thanks. 



    My initial thought was that a pump could be defined as machinery, it does have a moving part linked to a drive after all, but then felt the internal moving part would never directly come into contact with anyone - I say this as I imagine someone stripping it down without disconnecting the supply first. 



     



    I have worked from EN60204 and EN13849 in the past (for material handling machinery) and it seemed ‘relatively’ more obvious in how to meet the requirements of the MD. instrumentation and measuring equipment alone I find difficult to pin down in relation to CE marking. 



     



    The test rigs are generally one-off designs involving a fair bit of research and development (I’m mainly electrical design). While we use commercial off the shelf equipment, the completed test rig itself may not have ever been built before so it’s unlikely to have a type C standard - I’d love to find one though! 



     



    Another question ... would I be wrong in saying the MD always trumps the LVD if the equipment is indeed defined as machinery? In other words, can following EN60204, EN13849 (plus EMC standards) be good enough for at least the electrical design side of the control equipment? 



     


  • Former Community Member
    0 Former Community Member
    The LVD does effectively “trump” the LVD, not because it is more important, but because it has inbuilt the requirements of the LVD.

    They are mutually exclusive effectively.


    If you look at the definition of machinery, coming from the machinery directive, or HSE it does not require the moving part to be accessible to be covered under the machinery directive, it is more to do with the hazards that are posed and the definitions.


    I doubt also that you will find a c-type for a test rig!


    Try here for links to the directives and listings of harmonised standards for all the directives.
    https://ec.europa.eu/growth/single-market/european-standards/harmonised-standards


    Don’t forget 13850 for e-stops too! ;)


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