Economy 7 question

[Chris sparky]

Evening all.

I have been asked to price some flats for an architect. Have sat down with him and the client to go through drawings etc.
The flats are going to be on economy 7 tariff with storage heaters and immersion for hot water. Not to familiar with economy 7 meters but the architect has told me it will be one supply in, and a time switch in meter which changes tariff when econ 7 is in use. I was under the impression that it would be an on peak off peak supply with two supplies?? Phoned my local SSE and the guy told me the same. So basically the flats will be on standard rate (much inflated i'm guessing) and then everything on econ 7 after 22:30? Will the meter have 4 terminals or would i have to time control the storage heaters?

Any help would be appreciated.

 

[telectrix]

the meter will have 2 sets of readings. a dual tariff jobby. day and night. it's the same as a normal meter as regards wiring.

 

[Chris sparky]

OK thanks very much chap.

 

[7029 dave]

storage heaters should be on own cu (off peak) e7 meter has fifth terminal with integral time clock

 

[davethsparky]

Over the years they've had all sorts of different ways of supplying E7, but these days it is usually one meter with a permanently on output and a seperate time controlled output

 

[Richard Burns]

Yes as Tel says whole supply changes over at the random times the area DNO decide.

Just to hijack the thread, sorry, does onyone know if the signal from the time clock to the meter to switch the rate is captureable. Because the times are so varied, it can be very hard to set up a timer so that, say, storage heaters are using all the off peak times.
I was just wondering if the time clock gave a pulse or a continuous signal and if that could be detected by a CT coil or some such and used to operate a switch for then powering storage heaters?

 

[itselectric]

Why would you need to "capture" the time signal you won't get your electric any cheaper.Jjust use a time switch and contactor or apply for econ .7 that way you nightstores will run at the cheaper rate.


I think I may have mis-read your post.
I read it now that you already have and want to bring it in line. But that still won't make a difference
Am I beginning to waffle on.

 

[Richard Burns]

What I am saying is that if the economy seven times are for seven hours between 23:00 and 08:00 (a nine hour period) and the actual operating times may be:
on for 15 mins at 23:00, on for 45 mins at midnight and on from 02:00 to 08:00,
and then tomorrow it is:
on for 30 mins at 23:00, on for one hour at midnight and on from 02:00 to 07:30
it is difficult to set a timer that will permit high powered appliances to be on only when it is low rate and take full advantage of the low rate.

If you could tell the installation when it is on low rate and when it is on high rate and switch certain appliances on and off appropriately you would gain.

 

[7029 dave]

Integral time clocks on e7/e10,are set to gmt time, and they are staggered times of any thing up to 45mins apart on any one meter.The reason for this is to avoid simultaneous switching, the grid would not cope with such a serge lol. So in order to get of peak times look at the time on meter and set timers etc to time on meter.

 

[Jabbajaws]

I have a key operated prepayment meter which l had installed as l prefer not to have a giant bill mounting, which can be tempting to ignore.

I know l pay slightly more, which l don't mind as l rang round first and found a supplier that didnt charge rental for the meter, which is a pet hate of mine as they cream in thousands every year for stupid charges like rent.

They sent me an E7 key by accident and although l dont have storage heaters, l noticed that my lcd digital single phase, one tariff meter, was changing the prices @ 13p per kwh from 8am - Midnight, to 2p per kwh from Midnight until 8am.

Now that was for everything in the house, which l took advantage of straight away, doing all my washing and drying in the early hours.

Neighbours werent best pleased though, lol and they never asked me for the cash back when l got my new key...

 

[Chris sparky]

Thanks for replies lads.

So the whole place will be on econ 7 in the off peak hours. Didn't know it worked like that.

 

[Richard Burns]

All the modern one do it that way now, though there are still loads of the old style ones about, mechanical clocks and radio teleswitches some of which do separate supplies some of which do the whole supply.

 

[Chris sparky]

What I am saying is that if the economy seven times are for seven hours between 23:00 and 08:00 (a nine hour period) and the actual operating times may be:
on for 15 mins at 23:00, on for 45 mins at midnight and on from 02:00 to 08:00,
and then tomorrow it is:
on for 30 mins at 23:00, on for one hour at midnight and on from 02:00 to 07:30
it is difficult to set a timer that will permit high powered appliances to be on only when it is low rate and take full advantage of the low rate.

If you could tell the installation when it is on low rate and when it is on high rate and switch certain appliances on and off appropriately you would gain.

I see what your saying, not sure this is a good idea for the client or not. How would you tell the installation when it has kicked in though?
I their anywhere to find out exactly what times it goes on/off. Guessing it changes from night to night?

 

[Richard Burns]

Sorry that was a bit of a thread hijack.
The times are not specified by the power companies because they are based on demand at the time.
It is one of my bugbears about E7 and the current way of doing it that you cannot practically take full advantage.

In general you can say that from 02:00 to about 07:00 it will be E7 other than that a bit hit and miss.

 

[Chris sparky]

That's OK Richard. All is forgiven lol.