Fused Spur with Timer & Thermostat, electrical suppliers?

[Aenuff]

TLC have a fused spur with built in digital 7 day timer for about £40 but my local supplier had a discontinued one in their cataloge that also had a thermostat built in.

Basically I need about 10 of these to wire up storage radiators. No they're not on economy seven, are just on a normal ring. At the moment they simply plug into a socket with a timer on the plug! It works but people keep unplugging / bypassing the timers etc. Considering these are all new heaters I'd like to have them hard wired to a spur.

Anyone got any good online electrical suppliers who might do a similar item rated up to about 3Kw cheaply, ie. less than £40?

Tony

[Dave Plowman]

But wouldn't those same people just alter the time switch to bypass it?

[Christian McArdle]

If you find one, please post the results. I'm going to need one for my shed, but haven't found any. It is basically a programmable thermostat with 13-16A contacts and a fuse. Easy enough to do with a relay and FCU, but these take up more space.

Christian.

[Aenuff]

Possibly but its a lot more intimidating for someone to change a hardwired digital timer than a £5 plug in mechanical "thingy" plus they can't take off the timer just plug the heater straight into the socket.

Its the best idea I've seen so far, thats not to say someone here hasn't got a better one (hoping?)

Cheers

Tony

[Christian McArdle]

If this is more of a security issue, perhaps a central timer in a secure location might be more appropriate, with just a 13A thermostat/FCU at the heating position. Unfortunately, this may involve some wiring, although that should probably be done anyway, as you shouldn't really use a ring main for fixed electric heating.

Just using a local programmer, the timer controls can be overridden by the user.

Christian.

[stefek.zaba]

Gag. 10 storage heaters, on 'a' ring? You jest, surely: even for the lowest-rating storage heaters of 1kW you'd have 10kW = 40A loading on that poor little ring; with 2kW jobbies you'd have 80A! And if your tenants, students, migrant workers or whatever keep bypassing the timer, maybe they're cold, meaning the heaters are underpowered for the job they're trying to do? Are all these heaters in one property with one main supply, or are they spread among several houses?

Fixed heaters in regular use like these ought to have their own dedicated radial circuits (1-2 heaters per circuit depending on their rating). Then you can run dedicated switching for them back at/near the consumer unit (hmm, sounds just like an Economy7 setup, doesn't it?). Immersion-heater timers switch up to 3kW, and in some out-of-the-way padlocked cupboard might be good enough for your needs; beyond that lies the realm of control systems and contactors. But can you really not fork out for pukka dedicated-circuit Economy7 in the property/ies? Then you get your time-switching done for you, with no occupier intervention, and a far cheaper rate for the nighttime electricity thrown in... Or even a gas-powered wet CH system, if the property/ies have a mains gas supply!?

Stefek

[Aenuff]

dedicated-circuit

Stefek, as usual your response is perfectly correct and my OP probably a bit misleading. To clarify...

10 heaters, 3 x 3.4Kw + 7 x 1.7Kw spread across 4, possibly 5 - need to double check, separate rings. No more than 2 x 1.7 and 2 x 3.4s on any one ring. The building is three phase. We can get economy 7 but no budget for 2 years by which time there should be a budget for an oil fired zoned system with a couple of boilers covering the 2 main halves of the building.

All good fun!

Tony

[Christian McArdle]

When you say ring, you mean general purpose socket circuit? When you say

2x1.7kW and 2x3.4kW on one ring, you mean 10.2kW, or over 42A on a 32A circuit shared with other things? You've got a lot of diversity to find to get that lot working!

Christian.

[usenet]

Even 2 x 1.7 and 2 x 3.4 is marginal:-

Total of 10.2 kW, at 230 volts that's 44 amps, much too much for a ring circuit.

Even 2 x 3.4 kW is 29.5 amps leaving very little for anything else.