mains power and economy 7 q

[boaby]

Hi, firstly my flat is electric only with storage heaters, and i am on a Economy 7 tariff (2 seperate meters). In the living room im planning on wall mounting an lcd above where a combination storage/convector heater currently sits (Dimplex CXL24N). My plan is to get rid of the heater and put my av gear in its place.

Below is a pic of the two power supplies going into the heater. Now as i understand it the heaters storage circuit is plugged into the off-peak ring, and the convector circuit is plugged into the regular domestic ring - is this correct?

What i would like to know is can i swap the 'domestic' switch for a regular 3 pin wall socket? Do i need a specially rated/fused kind?

And secondly, I take it im not supposed to change over the switch thats connected to the off-peak ring? Illegal maybe?

 

[RF Lighting]

What i would like to know is can i swap the 'domestic' switch for a regular 3 pin wall socket? Do i need a specially rated/fused kind?

Providing the fan is actually fed of the ring (I.E. not a dedicated peak fan supply) Then there is no reason why the FCU can't be replaced with a standard socket (twin or single)

And secondly, I take it im not supposed to change over the switch thats connected to the off-peak ring? Illegal maybe?

I see no reason why you can't replace the off peak FCU with a socket, but this IMHO would be a waste of time as the off peak supply will only be live during off peak periods (through the night)

 

[JohnD]

... Now as i understand it the heaters storage circuit is plugged into the off-peak ring..

Not exactly. Storage heaters are usually each supplied by their own 16Amp radial (you will see a bunch of 16A MCBs or 15Amp fuses in a consumer unit near the meter - one per heater) they are not on a ring. You will notice that the heater switch does not have a fuse in it; this is because it is on an individually fused circuit.

As RF says, there would be no point in putting your AV on a circuit that will only be on during the night. But the "fan" supply is almost certainly on the socket ring, so you could change it to a socket; or, better, put an additional socket on it as a spur; or, using a dual box, a socket in the ring next to the existing FCU.

 

[boaby]

thanks for the replies guys. following your posts i googled abit more and fiddled with my consumer unit (<- always learning ) to see if i could figure this out. i found the following:

- spot on on JohnD, the three storage heaters in my flat each have their own individual MCB in the consumer unit, which, if i am understanding the numbers correctly, are rated at 20A.

- the convector circuit of the living room heater (plugged into the right FCU in the first pic) also has its own individual MCB which looks to be rated at 16A.

- and lastly it looks like i have two ring mains where the MCBs are rated at 32A.


SO, given that the convector circuit FCU isn't actually on a regular ring main and its MCB is rated at only 16A, is it still feasible to swap it for a 2-gang socket, with 4/5 pieces of gear connected?

 

[JohnD]

You can do. Since the socket circuit is only fused at 16A (and the wires are probably not thick enough to carry more than about 20) then it would be better not to plug in multiple heavy loads, like more than one heater/kettle/toaster/oven/washing machine/dishwasher/tumble drier at a time. If you do overload it, all that will happen is the MCB will detect the overload and trip (so no great harm done).

But you can plug in as many TVs/Videos/CD/DVD/radio as you can fit in your house as they are fairly low current. If you have a TV/HiFi set up, those multi-socket adaptors on a short extension lead are very handy, since you have a lot of things to plug in but draw hardly any current. In most other circumstances I discourage the use of adaptors.

You could also connect a double socket to the radial circuit as well as the FCU, though this will probably confuse people in future, since a socket (in a house in the UK) usually means it is connected to a ring. It might help to make a small label and put it on the outlet saying "16Amp Radial" so it is visible to anyone working on the outlet or plugging things in, but not otherwise conspicuous. This is because someone might turn off the ring circuit, and assume that all the sockets are now dead.

**warning** I am not familiar with your electric heater; if it has a heating element to provide heating from the non-off-peak supply during the day, it may have quite a high current load, so you would have to restrict the socket to low-power appliances like your TV and HiFi.

 

[boaby]

nice one.

It might help to make a small label and put it on the outlet saying "16Amp Radial" so it is visible to anyone working on the outlet or plugging things in, but not otherwise conspicuous. This is because someone might turn off the ring circuit, and assume that all the sockets are now dead.

excellent idea, didn't even occur to me.

thanks again. helps been great!