Dual Meter?

JOHNPT

In a dual meter where there is a night and day rate what is the clock situated beside the meter for? is it to switch from day to night rate? Can the time be adjusted on them and can it be changed by the consumer. On this particular clock there is 'on' at 11 pm ' off at 3am on at 8am. Is this correct or what way should they operate.

Thanks for replies in advance

fishdog

what is the clock situated beside the meter for? is it to switch from day to night rate?

Yes

Can the time be adjusted on them and can it be changed by the consumer.

No. Doing this could get you in big trouble!!! It is sealed just like the ESB meter.

On this particular clock there is 'on' at 11 pm ' off at 3am on at 8am. Is this correct or what way should they operate.

As far as I can recall night rate applies from 11pm to 7am GMT.

You can test when the night rate is on. Dry contacts are provided that close during this time. They are used to switch on storage heating etc.

JOHNPT

On the fuse board there is two 63 amp switch fuses. On the main breaker its live and feeds mcbs on board. On the other 63 amp its not live. There is a cable feeding this and from the top of this there is a cable feeding a 20 amp breaker which feeds the storage heater. Now the storage heater isint working. How can i test that (during the day) that the supply kicks in at 11pm to feed the storage heater ? Unless i am actually there at 11pm is there any other way to test its working. Is there two supplies from the meter one feeding day time rate and one feeding night time rate?

Thanks in advance?

davelerave

JOHNPT wrote: »

On the fuse board there is two 63 amp switch fuses. On the main breaker its live and feeds mcbs on board. On the other 63 amp its not live. There is a cable feeding this and from the top of this there is a cable feeding a 20 amp breaker which feeds the storage heater. Now the storage heater isint working. How can i test that (during the day) that the supply kicks in at 11pm to feed the storage heater ? Unless i am actually there at 11pm is there any other way to test its working. Is there two supplies from the meter one feeding day time rate and one feeding night time rate?

Thanks in advance?

ya theres two probably 2 supplies( the switches should be mechanically interlinked ).
is there a lite on the isolator switch beside the heater ? .you can energize the control circuit if there is one or you can test the circuit at the box with an ohmeter (15-30 ohms or so depending on size) and take a look at the timer /meter .if the timing is wrong or doesn't change. its an esb timing problem .you can prove it at nite if neccessary

fishdog

On the fuse board there is two 63 amp switch fuses.

Yes this is normal. On the supply side they are linked. They then provide 2 supplies from the same source. Each supply has its own 63A fuse. One fuse supplies all night rate appliences such as storage heaters. The fues supplies everything else.

If just one 63A fuse was used there is a danger that it would operate when all of the storage heaters kick in at once for the night rate.

ya theres two probably 2 supplies( the switches should be mechanically interlinked ).

No this is not correct. There is just one supply but as you say they are mechanically interlinked. This means that both fuses are either on or off.


It works like this:


16mm T&E Supply

---

Dual 63A sw fuse

---

63A Fuse 1

---

feeds a row of MCBs

---

MCBs feeds 1 side of contactor

---

Ohter side of contactor feeds a storage heaters

Contactor is energised by a pair of dry contacts in the meter cabinate. The contactor is only energised during off peak.


63A Fuse 2

---

Feeds all other electrical services

davelerave

fishdog wrote: »

Yes this is normal. On the supply side they are linked. They then provide 2 supplies from the same source. Each supply has its own 63A fuse. One fuse supplies all night rate appliences such as storage heaters. The fues supplies everything else.

If just one 63A fuse was used there is a danger that it would operate when all of the storage heaters kick in at once for the night rate.


No this is not correct. There is just one supply but as you say they are mechanically interlinked. This means that both fuses are either on or off.


It works like this:


16mm T&E Supply

---

Dual 63A sw fuse

---

63A Fuse 1

---

feeds a row of MCBs

---

MCBs feeds 1 side of contactor

---

Ohter side of contactor feeds a storage heaters

Contactor is energised by a pair of dry contacts in the meter cabinate. The contactor is only energised during off peak.


63A Fuse 2

---

Feeds all other electrical services

Maybe .from my reading he may have 2 supplies with the heating direct switched by the sound of it.ie:no control pair.i think the system you're referring to is where the incoming 16sq is looped into a seperate fuse to spread the load .it was a stopgap measure to prevent neozed fuses blowing or overheating

JOHNPT

In the fuse board there is two 63 amp sitch fuses and it looks like there is a seperate live going into the bottom of each fuse. One of the switch fuses then feeds the 20 amp breaker which feeds storage heater. There is no contactor in fuse board. So does this mean there is then as u said two supplies from the meter.
My problem is how can i check that night time supply is working to feed the storage heater unless i am there at 11pm?
If it dosent switch on at 11pm is it an ESB problem with the meter?
Will they call out to check this and will they charge for this?
Is it common to have two supplies from meter to fuseboard when u have night time meter. Is this the most common way its usually wired?

Thanks in advance for all replies appreciate it.

Thoie

JOHNPT wrote: »

My problem is how can i check that night time supply is working to feed the storage heater unless i am there at 11pm?
If it dosent switch on at 11pm is it an ESB problem with the meter?
Will they call out to check this and will they charge for this?

If you phone them and tell them you think the clock is wrong, they'll call out and sort it, no charge. It's pretty easy to see if the clock is wrong though - at this time of year there should be a little triangle pointing to the current time - during the summer it will be an hour out. The off at 3 and on at 8am sounds wrong - mine is on at 11, off at 7, and that's it. ESB will sort that out as well.

If the timer is OK, and there's still no power to the heater (make sure you don't have the thermostat too low), then it's an electrical problem within your house that you'll have to get an electrician for.

As for testing whether the thing comes on - I'm not sure. If there's a light beside the storage heater like mine has, maybe set up a video camera to record for a few hours? Set the clock right on the camera.

If you have internet access in the house, leave a laptop there overnight with a webcam setup? Go back the next day and see if the storage heater is warm? The light should be gone off around 7am (give them 10-15 minutes leeway). Setup some kind of bomb timer fuse to the storage heater so that the house explodes if it switches on? I'm running out of ideas here! Hook up a kettle to the storage heater, stick an egg in it, and if the egg is boiled the next day, it works?

davelerave

JOHNPT wrote: »

In the fuse board there is two 63 amp sitch fuses and it looks like there is a seperate live going into the bottom of each fuse. One of the switch fuses then feeds the 20 amp breaker which feeds storage heater. There is no contactor in fuse board. So does this mean there is then as u said two supplies from the meter.
My problem is how can i check that night time supply is working to feed the storage heater unless i am there at 11pm?
If it dosent switch on at 11pm is it an ESB problem with the meter?
Will they call out to check this and will they charge for this?
Is it common to have two supplies from meter to fuseboard when u have night time meter. Is this the most common way its usually wired?

Thanks in advance for all replies appreciate it.

it looks like the nsh is direct switched john.theres a few variations on dual-tariff if this is what you have . often the time stops thats what i see most should be easy to spot .you can energize the heater or take a reading with an ohmeter at the main switch to test it if you know what you're doing

fishdog

it was a stopgap measure to prevent neozed fuses blowing or overheating

No this is the way the ESB want you to do it as shown in their interface book given to electrical contractors.

davelerave

you would need to use 25sq tails anyhow with that system fishdog.and even then overload protection is effectively provided by the esb-cut-out due to the bypass at the main switch-fuse.the ESB created the problem in the first place with the gold shield system they designed,i think this was their solution to the problem.
a better system is the 80amp dual-tariff with contactor switching(25sq tails 80amp single-pole main mcb) or dual tariff direct switched with 2 sets of 16sq tails if it's available.

davelerave

I had a look at the esb handout (method 2 day/nite )for that particular arrangement they've specified tails to comply with etci regs which i think would mean 25s .here,i think also the esb cut out would effectively provide overload protection that could be a problem i would need to check but its never been acceptable for any other domestic metering arrangement assuming im reading it correctly