by ericmark »
Wed Jul 06, 2016 11:18 am
There has been some debate about the so called lollipop method of installing a ring final, the method is however used. There is also the grid switch method with a series of radial circuits however there is a problem getting 6 mm cable into a grid switch likely you would need something to change from 6 mm to 2.5mm.
So the problem will all ring finals is high load need the origin can cause and over load on one leg. Where the load is kept to no more than 2 kW as recommended in the wiring regulations for fixed appliances off a ring final there is not a problem. Although a kettle is 3 kW it's run time is short so it will not over heat a cable.
An immersion heater however runs for a long time so we traditionally run a dedicated supply. As to why I fail you understand, but it seems in the UK it is common to combine cooking and laundry into the same room, so kitchens often have washing machines and tumble driers in them, I suppose because traditionally that was where we found all the hot water! But this means the kitchen can have a host of static items all drawing more than 2 kW which should really have dedicated supplies.
Location is everything, if the origin of the lollipop ring has the tumble drier, washing machine, and dish washer in a line then goes around the kitchen there is a high chance of overload, but if the same three items are on centre of ring or spread around the room there would be no problem.
When we do some alteration like turning a cooker supply into a lollipop ring we sign the minor works to say we understand what we are doing and take responsibility for what we have done, which includes testing to see our ring is really a ring. If the work is done with due consideration for loading there is no reason why the cooker supply can't be turned into an array of sockets all around the kitchen. But it is not as simple as connect them all up and trust to the Lord.
