maximum demand and diversity

[SDELEC]

If your fitting a new split or high integrity board didn't they supply 1x 63amp and 1x 80 amp RCD with it?

Have not bought one yet, i am a bit limited as to which board I choose due to the space available, The wylex 17th ed fits the bill. it comes with 2 x 63a rcd. would you recommend swapping one for 80a?

 

[malcolmsanford]

Really in all honesty current rating of the RCD is not that important as it is providing fault protection and not overcurrent protection. So really if you wanted you could fit a 125amp one as long as the important part which is the 30mA in a domestic situation is there.

IMO I would fit the 80amp as now installations are becoming larger with showers and cookers etc, and whatever else is going to hit us in the future.

 

[Sparky Ninja]

when I asked my Elecsa assessor at my assesssment for advice on max demand calcs, he told me about the book - The IEE Electrical Installation Design Guide, which is quite a helpful book, but he also told me that most sparks just add the breakers up and times by 0.4

That's the book I use and stick with.



here is a calculation I did last week.

 

[gpz900jim]

I asked my assessor about whether I would have been better fitting the 80a rcds instead of the 63s . He said that the rating on an rcd is its service rating and not its maximum load capacity,