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https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl DIY Forum >> Electrical Questions >> Ring Circuits https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl?num=1098647337 Message started by Eddy on Oct 24^th, 2004, 8:48pm

Title: Ring Circuits
Post by Eddy on Oct 24^th, 2004, 8:48pm

I am not an electrician and would be glad if somebody would explain the following to me.

My storage heaters are connected to the Economy 7 tariff ICU on radial circuits. I understand that this is the norm for storage heaters. But why could they not have been connected to an independent ring circuit?

The panel (convector) heaters in the bedrooms have ratings of between 1500W and 2000W. They, however, are connected to spurs running off the ring circuit suppling the power points on the top floor. If all the panel heaters were all switched on, the consumption would be quite high. Would this overload the circuit? And if so, is the installed 30-amp circuit breaker enough?

Title: Re: Ring Circuits
Post by sparkyjonny on Oct 24^th, 2004, 9:47pm

Radial circuits offer a better form of power distribution, and heaters are far better off on dedicated radial circuits. With rings, dependant on resistance due to increased load, only around 2/3 of the total circuit rating is available on each leg. Whilst this offers a satisfactory form of distribution for ring mains with generally low-current appliances being plugged in, it is not ideal for high-load heaters.
You need to work out the total load of all your heaters, and other commonly-used appliances (fridge/freezer) on the circuit, and see whether this could come near or exceed the circuit protective device (fuse/MCB) rating -> I=P/V. If it does, they need an extra dedicated circuit, or your existing circuit needs splitting into two.

Title: Re: Ring Circuits
Post by plugwash on Oct 24^th, 2004, 11:32pm

the ring was designed for a specific reason

to allow 2 3kW heaters to be plugged into *any* 2 sockets in a house still leave enough power for small appliances and keep the amount copper used to achive this down

storage heaters are a totally different type of load. They are not normally moved around. They switch on and off all together. They need about 3KW each and noone would normally wan't to put small appliances on the off peak systen

so a ring wouldn't gain you anything over putting them on thier own individual 15A/16A radials