Circuit Layout

[Engineer54]

I've chased faults around RFCs, once using 25kHz pulsed injection equipment. You can have a perfectly sound ring but it might have extended non fused radials. You might have a ring that has interconnections. A small ring with spider connections feeding more than one socket outlet is particularly common in older properties.
Faults on rings are not particularly difficult to find but they do take longer than a single radial circuit. Particularly when you have a damp socket that is causing unwanted tripping of the RCD.
Perhaps the main reason for using lots of radials supplying a limited number of sockets is the reduced inconvenience when a circuit has to be isolated for a period of time, perhaps when you are called at 7pm at night by a confused customer. The solution then is obvious. You don't have to work late but come back at a more convenient time and they can move the appliances over to another socket rather than having half the house without power.

Hey don't get me wrong, i have nothing against the use of radial power circuits at all. But an installation design should be based on the needs/requirements of the installation, not on an electricians preference based on his ease of testing, or because of a lack of fault finding skill's on FRC's... Can also be very costly for the homeowner too, all those unnecessary circuits back to the CU!!!

 

[ackbarthestar]

Hey don't get me wrong, i have nothing against the use of radial power circuits at all. But an installation design should be based on the needs/requirements of the installation, not on an electricians preference based on his ease of testing, or because of a lack of fault finding skill's on FRC's... Can also be very costly for the homeowner too, all those unnecessary circuits back to the CU!!!

I agree, the cat can be skinned from the bottom up or from the top down;:wink_smile:.

I install both rings and radials. The preference for kitchens and utility rooms is a ring as stated earlier, but sometimes if an item of equipment I want to keep separate, such as a freezer, I place on its own radial. upstairs Bedroom sockets, where the loading is minimal are usually on radials.

I like the German method of wiring where sub-mains go to each room and power and lighting radials are fed locally, but that's choosing to skin the cat from the side. and is purely personal.