CB Placement

[sparky999]

I'm Installing a 32A Circuit Breaker For a new Ring main, the board only has 4 circuits 32A,32A,16A and a 6A.

When installing a new Circuit Breaker with spare ways in the board do you just take the spare way after the 6A or do you move them all over so it goes down in order again.

Just a thought as i only do new builds normally and i always work highest CB to the lowest. Like this so should i do the same

 

[Andy™]

normally just stick it where it will fit. i dont think there is a regulation to say highest rating must go next to switch

 

[sanny]

its good practice to have the highest loads nearest the main switch but when doing a CU change you put them where the cable lengths allow

 

[a1]

I'm with Sanny, on this one.

 

[Riggy]

I agree - highest nearest isolator/RCD where possible, but this is only through habit - is the busbar really going to melt if the shower MCB is at the far end? - I don't think so!

Riggy

 

[Evans Electric]

Its one of those old wives tales ( or old sparkies ) I believe . The live rail will carry the full load current so stick it where it fits. ( Move them all along ! Life is too short )

Deke

 

[batty]

I think manufacturers recommend they are spaced so high load stuff is not next to other high load stuff as the circuit breakers can get warm. But I usually put them from highest to lowest if possible.

Batty

 

[sparky999]

Yh i have always done high to low, just wanted to see what you guys do.

 

[SLIPSHOD & SLAPDASH]

Its one of those old wives tales ( or old sparkies ) I believe . The live rail will carry the full load current so stick it where it fits. ( Move them all along ! Life is too short ) Deke

Its not an old wives tale. Its good workmanship. On additions like yours i would just stick the breaker in the next hole. Dont get involved in moving every other cable in the board and testing and what about any certs out there with the 'old' circuit positions.

 

[GreekIslandLover]

If it's a rewire I leave the cables long enough to put all circuits in order of current capacity, and split them over the two RCD's. If I'm adding a circuit to an existing board I'd put it on the end to save disturbing the existing circuits, relabelling the board and confusing existing certs. If it's a consumer unit change, I'd try to put them in current capacity order, but if I have short cables I'd place the breaker wherever I could get the cables to fit properly rather than crimp/extend them.