by BLAKEY1963 »
Sat Jul 28, 2007 12:57 am
[quote="nchw"]I'm fitting a split-load consumer unit to replace an existing ceramic unit in a basement flat. Expected load will be a shower, cooker, ring mains, immersion heater - usual domestic stuff. I've decided to go for a 10mm cable to the shower. Problem is what size RCD - 63A or 80A ? Can anyone explain how to calculate the best size.
Chris.[/quote]
CHRIS
U CALCULATE MAXIMUM DEMAND OF INSTALLED CIRCUITS
TO SELECT MAIN SWITCHES AND SPLIT BOARD RCD.
A FACTOR CALLED DIVERSITY IS TAKEN INTO ACCOUNT.
DIVERSITY IS A PERCENTAGE OF EACH CIRCUITS CURRENT
DESIGNED CAPACITY. FIGURES FOR DIVERSITY CAN BE FOUNDIN OSG BS7671. I WOULD SELECT 100 AMP MAINSWITCH AND
80 AMP MCB. OF COURSE I AM SURE WHEN U LOOK AT DOC S PROJECT SITE U WILL KNOW THAT THIS IS NOTIFIABLE WORK AND THE SELECTIONS OF SWICHES WOULD BE CHOSEN BY BY YOUR PART P REGISTERED SPARKY.
BLAKEY1963
