I'm checking out the electric wiring in my new house trying to see if there is anything I need to get put right before I decorate and live in the house properly.
So, I've been reading up and I'm confused about derating grouped circuits.
There is trunking(1.5m long 50mmx25mm) in my kitchen with the cooker cable(10mm) and two ring mains i.e. 4 cables of 2.5mm.
The cooker cable has a 32A MCB has two ring mains(Kitchen and downstairs) also have a 32A MCB each.
Should these grouped circuits have been derated(e.g. x0.7) or does nobody bother with group derating in domestic instations?
What about the 2 meters of trunking(there are two truckings actually) where all of the cables from the consumber unit travel up the wall together? Surely this is circuit grouping and would mean that all the circuits also need derating?
It must be pretty similar to every other house in the country but I'm assuming that most house circuits are not derated?
Do I need to get somebody in to derate the MCBs(and suffer nuisance trips!) or is the installation typical and nothing to worry about.
I also have a similar concern about all the cables traveling from the consumer unit and into the ceiling space between joists where the hot radiator pipes flow. It must get pretty hot in there with nowhere for the heat from the pipes to dissapate. Should I get all the circuits be derated to account for this? or maybe I should just insulate\shield that part of the space bettween the pipes and the cables? Again, this is probably a common situation and I'm assuming that not everyone has derated to 20A MCBs?
Can anybody explain or reconcile the derating regulations, with what is found in typical house installation?
Thanks for any help!
So, I've been reading up and I'm confused about derating grouped circuits.
There is trunking(1.5m long 50mmx25mm) in my kitchen with the cooker cable(10mm) and two ring mains i.e. 4 cables of 2.5mm.
The cooker cable has a 32A MCB has two ring mains(Kitchen and downstairs) also have a 32A MCB each.
Should these grouped circuits have been derated(e.g. x0.7) or does nobody bother with group derating in domestic instations?
What about the 2 meters of trunking(there are two truckings actually) where all of the cables from the consumber unit travel up the wall together? Surely this is circuit grouping and would mean that all the circuits also need derating?
It must be pretty similar to every other house in the country but I'm assuming that most house circuits are not derated?
Do I need to get somebody in to derate the MCBs(and suffer nuisance trips!) or is the installation typical and nothing to worry about.
I also have a similar concern about all the cables traveling from the consumer unit and into the ceiling space between joists where the hot radiator pipes flow. It must get pretty hot in there with nowhere for the heat from the pipes to dissapate. Should I get all the circuits be derated to account for this? or maybe I should just insulate\shield that part of the space bettween the pipes and the cables? Again, this is probably a common situation and I'm assuming that not everyone has derated to 20A MCBs?
Can anybody explain or reconcile the derating regulations, with what is found in typical house installation?
Thanks for any help!