Contactor for Heating Radial

[EastCoastPete]

Hello All,
I've a 1 bedroom flat installation. All standard but the customer will AirBB it and wants a master switch to encourage guests to turn off the (3x 1Kw) wall heaters when they leave. I'm thinking 16A contactor, any good /bad makes or takes on this route?
Thanks,
Pete

 

[Spoon]

I like Schneider.
Personally I would go a bit bigger than 16A. Just thinking of inrush and longevity of the contactor. The price is not much more for a 25A.
See what others say.

 

[pc1966]

A contactor also allows the sort of 'insert card to work' arrangement that you see in hotels to stop wasting power on heating/AC/lights when guests are out.

Heating won't have any inrush (unless motors for heat pump arrangements) but if there is any chance that more is added later then going up to 25A allows for that with minimum trouble.

 

[westward10]

Something like this.

BG 16A Hotel Key Card Switch - White | ElectricalDirect

www.electricaldirect.co.uk

 

[pc1966]

Something like this.

Odd how that advert says "Load Rating - 1800W for resistive, 800W for inductive"?
[automerge]1587997606[/automerge]
Says the same on the BG web site:

16A Hotel Key Card Switch | Moulded | BG Electrical

BG Electrical Moulded 16A Hotel Key Card Switch comes with a LED locator and a 30 seconds power-off delay. Colour coded terminals with backed-outs.

www.bgelectrical.uk

 

[westward10]

Inductive will always be considerably lower and they only normally control a contactor.

 

[EastCoastPete]

Thanks for all comments, looking at specs, like the key card,
best,
Pete

 

[pc1966]

Inductive will always be considerably lower and they only normally control a contactor.

It is more the point that a '16A' device ought to be 3.6kW resistive (i.e. more than 1800W)!

 

[westward10]

It is more the point that a '16A' device ought to be 3.6kW resistive (i.e. more than 1800W)!

I am not convinced 16A is its rating as the BG catalogue does not indicate this 16A just the resistive and inductive rating.

 

[pc1966]

I am not convinced 16A is its rating as the BG catalogue does not indicate this 16A just the resistive and inductive rating.

Looking at the data sheet here:

https://www.bgelectrical.uk/public/downloads/data-sheets/euro-module/16A_Hotel_Key_Card_Switch.pdf

What they call resistive load on the quick form data is actually incandescent lamps, so it probably is 16A resistive without inrush! Inductive load is fluorescent lamps.

 

[radiohead]

If it's just a 3kw load why not switch them direct?
edit
Just seen the card reader idea, so the above is probably redundant!

 

[pc1966]

Most hotels that use the card reader cut everything when out, but that is a right pain if you need something charged while out (tablet, electric toothbrush, etc).

If you are thinking of using a big contactor to switch a lot you might want to consider modifying a big split-load style of CU so you can have one RCD powering MCB for one or two labelled USB 13A sockets that are live all the time, plus maybe outside PIR lights and any entrance hall lights, etc, and of course the card switch to operate a contactor (probably bigger like 40A or more depending on the loads).

The contactor would need some protection if not part of the CU (you might be able to fit it in) so could come from a non-RCD MCB at 40A or more. Yes, selectivity is poor if MCB in series but probably tolerable, but if it can go in the CU and not need protection (as loads are all protected) it would be much better.

In turn would go in the feed to the 2nd RCD with the MCB for heating, lights, main 13A sockets for TV and similar (cooker stuff?).

 

[pirate]

In practice, most folks staying in a hotel who want to charge stuff/leave the aircon on, take the key-card out, stick their Tesco card in, and go out for the day. Some key-card switches read the card contacts, so this trick doesn't work, but in the main it's just a switch activated by the bit of plastic being inserted to activate the contactor.

 

[pc1966]

Damn! You have revealed my dastardly trick to everyone! <twiddles moustache>

 

[davesparks]

In practice, most folks staying in a hotel who want to charge stuff/leave the aircon on, take the key-card out, stick their Tesco card in, and go out for the day. Some key-card switches read the card contacts, so this trick doesn't work, but in the main it's just a switch activated by the bit of plastic being inserted to activate the contactor.

I just get a second keycard from reception to do this with.

 

[pirate]

Fair enough, davesparks, but if you are running a holiday rental and only provide one keycard to your guests, you will find they use this method to leave the aircon on all day while sweltering at the beach then complain how hot it is and what a good job it is they "bypasssed" the keycard system while they were out...so they come back to a cold apartment...and pour drinks and sit out in the sun all evening, with the doors and windows open, while the electricity costs rack up enormously. I know this...and let me tell you the electricity charges in Spain are quite ferocious.