Replace 2-way light switches with timer switches

[tcarnell]

Hi everyone.

I'm looking to replace 2 2-way light switches (one in our hall and the other on the landing) with timer switches, so that they turn off automatically after a set period of time if they aren't manually switched off.

I've seen the Elkay range of touch timers (links below) but I'm confused as to which type is the right one for me. There's a 2 wire version, a 3 wire version (they refer to both of these as 'masters') and a 3 core version, which they call an 'activator'.

2 wire - https://bit.ly/2WTLNZy
3 wire - https://bit.ly/3aSluLw
3 core - https://bit.ly/34VuY4O

Can anyone enlighten me as to which one (if any!) is suitable for my situation?
I'm also not tied to Elkay, they're just the first ones I found, so if anyone has other suggestions please let me know.

Thanks in advance for all help and advice

All the best,
Tony.

 

[conny]

I'm not an electrcian by trade so if I am wrong then hopefully someone will correct me.
To me the 2 wire one seems to be for a single light and switch so therefore not suitable for 2 way switching.
The 3 wire needs a neutral for some unknown reason so I don't think that is suitable either as the chances are, you don't have a neutral to your current switches.
The third link is for a Slave unit but you would need a Master unit to control it and, as neither the 2 wire or 3 wire in your links is called a Master unit then I, personally, don't think these are suitable.

 

[333rocky333]

If you have a Neutral at the switch then 3 wire master is always better.
If no Neutral then only the 2 wire will work, unless you install a Neutral.
For Two way, A master can only be used with a slave, what do you mean by (3 core) and Activator

Fitting may not be as easy as you think as often the wiring has to be reconfigured, sometimes so the switches are in Parrallel, whilst some Elkay stuff needs a single Trigger wire.


https://www.tlc-direct.co.uk/Technical/DataSheets/Elkay/EK560A1.pdf

 

[ericmark]

In the main where stair wells etc have timed switches they are not two way or intermediate, often simple pneumatic timed they are in parallel as switched off by time.

Energenie MiHome do make two way switches which can have up to three times set, more if using IFTTT but it needs to switch on and off at set time, so would not really help, I use one as my bedroom alarm clock.

If some one fitted timed switches on my stairs I would get rather upset, in the days with 60 watt bulbs in stair wells the idea of timed switches saved money, but with 7 watt bulbs, the 24/7 current used by an electronic time switch would likely exceed the money it saved turning off the lights, and also has a safety problem. Having lights which may switch off while on the stairs is not really a good idea.

 

[SUNRAY]

In the main where stair wells etc have timed switches they are not two way or intermediate, often simple pneumatic timed they are in parallel as switched off by time.

Energenie MiHome do make two way switches which can have up to three times set, more if using IFTTT but it needs to switch on and off at set time, so would not really help, I use one as my bedroom alarm clock.

If some one fitted timed switches on my stairs I would get rather upset, in the days with 60 watt bulbs in stair wells the idea of timed switches saved money, but with 7 watt bulbs, the 24/7 current used by an electronic time switch would likely exceed the money it saved turning off the lights, and also has a safety problem. Having lights which may switch off while on the stairs is not really a good idea.

I agree with all of this. In the toilets of an office block I worked in it cost more to run PIR sensors 24/365 than any savings in reduced on time.

 

[333rocky333]

I agree with all of this. In the toilets of an office block I worked in it cost more to run PIR sensors 24/365 than any savings in reduced on time.

But do you think the Life expectancy of the fitting would increase them not being on so much, then again I usually find its the sensors that fail anyway

 

[SUNRAY]

But do you think the Life expectancy of the fitting would increase them not being on so much, then again I usually find its the sensors that fail anyway

My involvement was adding meters all over the building and integrating them onto the BMS. The been connters soon jumped on the toilet lighting and discovered it would be turned on by the first person to enter and off by the cleaners so generally about 12 hours a day. Sensors were fitted by another contractor and the consumption went up. I was still on site and spent lots of time in BMS panels in risers adjacent to the toilets and it was quite obvious to me that the lights were pretty much on all day due to the amount of people using the toilets.

I've always considered leaving things on saves the switch-on surges it certainly seems to be the case with other electronic kit.

When I was at school we had an old mansion house, one of our projects involved measuring the building and making a scale model. We ended with an unidentified window and a space which appeared to have no apparent means of access but a passage seemed to be silly as the last room it served could have been 4ft wider and saved building a wall.
Loads of banging on walls seemed to point to 2 positions which sounded different, one from the passage and one from the adjacent room. Eventually the caretaker was tasked to make a hole. there was an old roll topped desk, several chairs and a wardrobe sized cupboard but the unexpected thing? the light was on, almost impossible to see any light as everything was very black. The adjacent room had been the Games teachers office for 20 years before the new building was added, he and the other long serving teachers Knew nothing of the room.
The really sad thing was the whole building had fairly recently been rewired and that old rubber wiring had been included on a lighting circuit and noted on the paperwork as left connected as it presented an unknown load.

How often do bulbs fail at switch on compared to having been on for a while?

 

[ericmark]

It seems in a fire house a fitted 1901 and not switched off is still lit so likely some support in not switching off, however started as 60 watt bulb, now giving out around 4 watt and I am sure if not a world record holder it would go in the bin.

My son pointed out how much power a smart bulb used when off, we have for years had the one watt stand-by limit, but it is one watt per device, so 8 bulbs in a chandelier and you could be using up to 8 watt and still be within the agreed limit.

For a lamp in the EU it must state the lumen output and if not dimmable and watts or mA input. And if lumen is not given then clearly for decoration only, but it seems it does not need to list stand-by power. Be it a bulb or an electronic switch, wifi, bluetooth, PIR, dimming switch they they must use some power, and the good ones say how much. I assume if it does not give stand-by use, it is a toy.

My landing has a 10 watt LED bulb, so if I consider it over 10 years, that is around 900 kWh, at 20 p per kWh that's around £18 to power it 24/7. So to pay for its self the device plus fitting costs must cost less than £18, I would say the device needs to cost less than £5 to be worth bothering with.

One even has to ask at such a low saving is it even worth the debate? OK some on down the hill has drive lights which I wish were not there, as it stops my night photography, but although I switch off the landing light, in real terms not even worth the price of a simple switch today.