Re BS Standards for Distribution boards and Enclosures

Hi there 

I've recently been involved in a project to look at replacing old Distribution Boards and there Enclosures but we have been asked a number of questions in regards this these being as follows:-

Question 1 - Determine the impact to using the present array of MCB's within the current Distribution boards which are some 30-40 years old in line with what the current standards BS EN 61439-3 compared to the old Standards BS EN 60439-3?

Question  2 - What criteria determines if we do or don't need to use RCD's/RCBO's?

Question 3 - Can you swap the actual MCB's that are used in the current Distribution boards which are 30-40 years old with the latest new standard MCBs without changing the entire board?.

Parents
  • I am not clear on what you are proposing to do.

    If you mix and match, you become the manufacturer of the board and, accordingly, responsible for ensuring that it meets all the requirements of BS EN IEC 61439-3. That may be difficult if some of the parts are to BS 60439-3.

    See Note 2 to 536.4.203.

  • Basically the idea was rather than replace the distribution board could we use the existing board and replace the old MCBs with the modern equivalent MCB.

Reply Children
  • The reason for this is that the existing board we are struggling to find the exact equivalent board that matches in dimensions. As we are concluding that it could be bespoke and not a COTS board. 

  • Ian, perhaps you need (one or more) new bespoke boards?

    In principle, you could perhaps replace the skeleton (for want of a better word) of the DB(s) with a modern one, which would be compatible with current outgoing devices. Then you would need a cover whose apertures match the new devices. That would not be too difficult to fabricate, but now you really are the manufacturer.

    As Andy has mentioned half an hour ago, BS 60898 does not specify standard dimensions. I have to admit, I do not know where the standard 18 mm width is specified.