Peak demand load controller

[Ian1972]

Does anyone know of a controller that can turn off loads as the demand goes up?

I have a house with 10x2.7kw heaters installed, the obvious problem is if there all on that's 27kw on a 100amp single phase property, there's no option to go to 3 phase and no capacity for any other appliances to run in the house, I need to somehow turn off heaters if a washing machine or other high current appliance is used, appreciate any help here

 

[James]

Does anyone know of a controller that can turn off loads as the demand goes up?

I have a house with 10x2.7kw heaters installed, the obvious problem is if there all on that's 27kw on a 100amp single phase property, there's no option to go to 3 phase and no capacity for any other appliances to run in the house, I need to somehow turn off heaters if a washing machine or other high current appliance is used, appreciate any help here

I could sort out a bespoke control system for you.

however, is it actually likely that all 27 heaters are running at full power continuously for any period of time?

diversity calculations would be worth considering in this case I think.

 

[Ian1972]

I could sort out a bespoke control system for you.

however, is it actually likely that all 27 heaters are running at full power continuously for any period of time?

diversity calculations would be worth considering in this case I think.

Hi James, thanks for the quick reply

I need to go to the property to have a look at exactly what's there so I'll have more info after I do that, I don't think they will ever be able to have all heaters on at the same time so maybe time schedules for different rooms like only running one heater in a bedroom in the day then running two at night and switching the living areas to one heater at night but I need to have a look and speak to the customer to see what he needs, can you give me a ball park figure for a bespoke controller just so I have a rough idea, cheers

 

[James]

plc £200
output module for plc £200
current sensor £50
enclosure £60
contactor £30 x 27 =£810

£1300 for parts, assuming that you want to control each heater individually so the load can be cycled around.
could be made a lot cheeper if you want to control heaters in banks of say 3

its an unusual problem and would need a more detailed spec of the installation to have any real idea of cost.
[automerge]1588103082[/automerge]

View: https://youtu.be/Y44YaTeo7mM


worth a look before you spend a fortune fixing a problem that is not there.

 

[Ian1972]

plc £200
output module for plc £200
current sensor £50
enclosure £60
contactor £30 x 27 =£810

£1300 for parts, assuming that you want to control each heater individually so the load can be cycled around.
could be made a lot cheeper if you want to control heaters in banks of say 3

its an unusual problem and would need a more detailed spec of the installation to have any real idea of cost.
[automerge]1588103082[/automerge]

View: https://youtu.be/Y44YaTeo7mM


worth a look before you spend a fortune fixing a problem that is not there.

I think there's around 10 heaters at 2.7kw each so won't need 27 contactors that should make things a little easier to control, I could also look at having them in banks of 2 so might only need to control 5 outputs so that might bring down the material cost, does that price include your programming of the PLC or is that extra and your cost for assembling the panel, when I've had a look I'll have a better idea I was also thinking of thermostats in each room, could they simply be connected to the contactors coil? Or would you need them going to the PLC

 

[pc1966]

It is not off-the-shelf cheapness, but it is probably a whole lot less than the DNO will charge for a supply upgrade!

 

[davesparks]

I have a house with 10x2.7kw heaters installed, the obvious problem is if there all on that's 27kw on a 100amp single phase property,

How long has this property had that many heaters, is this an existing installation or a new planned installation?

10 2.7kW heaters does will not, in reality, equate to 27kW demand on the supply. You've not applied any diversity.

Heaters cycle on and off according to their thermostats, they won't all be on at once.

If this is an existing installation then has there been any problem with overloading?
Has a load study been carried out to establish the actual maximum and average demand?

If this is a new proposed installation then I would suggest a serious rethink of the design, 10x2.7kW heaters is hardly the most energy efficient of designs!