20% rule

[ONIT]

Has anyone come across 20% rule on the new 17th ed boards

Is it on the whole of the board. or each sub section, ie 20% fist rcd, 20% second rcd ect. ect.

cheers....

 

[wayne]

dont understand this one ????

 

[rumrunner]

dont understand this one ????

20% is one 5th of 100

 

[Bane]

And 4 is one fifth of 20

 

[ONIT]

sorry if installing new cu you would leav 20% space is ,, ie 8 circuits 10way cu,, 10 circuits install 12 way cu so (20% expansion space) is it on all the board or each sub section

So if installing 17th ed board with mains isolater, rcd 1 ,, rcd 2.. would you have too leav 20% expansion on each rcd i hope thats a bit more clear

cheers

 

[Bane]

*Watches Wayne chase the tumbleweed as it rolls by*

 

[ONIT]

what stage did you just get kicked off

 

[wayne]

ahhhhhh! now i understand onit is on about spare capicity .as far as im aware there is no requirement to leave any space spare. if you fill one board then add another and another.........
we tend to go for 25% spare the current db im doing has 50% spare ,but thats the client s choice ! (24 triple pole ways)