Wiring an Elkay Columbus 400A Pneumatic Time Delay Switch

[Flipjango]

Hoping someone can help me with fitting one of these please? I'm a normally competent landlord, and have safely managed to do simple electrics such as wiring lights and switches over the last 20 years. I own a flat in a building with a tiny communal hallway. It has one light currently wired to a simple rocker light switch. There are two flats in the building and the communal light is attached to my flat's meter. The other tenants are constantly leaving it on which is costing my tenants money, so they've asked me to change it to a pneumatic switch which seemed simple. There's no complicated wiring - its just one ceiling rose and has just simple live, neutral and earth.

I thought it would be easy but I've opened the package to find the contacts are Com, NO and NC. I was expecting a normal wiring diagram with live earth and neutral so this has thrown me a bit. I basically understand the concept of normally open and normally closed, but there is no diagram on the packaging telling me which (L, E N) goes to which. Would anyone be prepared to advise please? I'm sure there will be lots of people telling me to get an electrician, and if I can't work it out I will, but I am generally quite comfortable doing simple wiring so I don't think this is beyond my capabilities, I just don't have the theory training! Which do I wire to which please?

 

[EFLImpudence]

A picture would probably be best to make sure, but -

If there is only one switch, then:

L in to COM and L out to NO, Neutrals(if any at the switch) joined together and Earths joined together.

For tenants, an electrician probably should be employed because, with no disrespect, you obviously do not know what you are doing.

 

[Colin Brenton]

If it's a single switch (not one at the top of the stairs, one at the bottom etc?), then just put one wire from the existing switchplate into the COM, and the other wire from the existing switchplate into the NO. Leave the NC terminal unused.

Any separate connector blocks containing multiple earth or neutral wires in the back box can be left alone.

The theory is that on the new switch, COM and NC (normally closed) are joined 99.9% of the time, other than when the button is pressed in. When that happens, until the delay time runs out, COM and NO (normally open) are joined.

As you want your light on then, and off the rest of the time, connect the switch wires as described.

Hope this helps, but shout if it doesn't work.

 

[flameport]

I'm a normally competent landlord,

Pay a competent electrician to do your electrical work.

and have safely managed to do simple electrics such as wiring lights and switches over the last 20 years.

Is that because it was all done properly as an electrician would have, including the appropriate testing, certification, notification where required and having the whole lot inspected and tested every 5 years as required by law?
or that it was lashed in and eventually worked after 6 attempts and nothing has injured or killed anyone yet?

? I'm sure there will be lots of people telling me to get an electrician, and if I can't work it out I will, b

You are asking how to wire up a light switch, one of the simplest things possible.

 

[oldbutnotdead]

Is there a reason for the light being left on all the time? (Poor switch positioning sounds likely).
Are there any foreseeable hazards if people use that lobby with the light switched off?
Might be much better served with a 1 or 2W LED lamp permanently on. Easy to calculate the cost & refund your tenant (1 watt for 1 year consumes 8.7kwh).

 

[EFLImpudence]

Might be much better served with a 1 or 2W LED lamp permanently on. Easy to calculate the cost & refund your tenant (1 watt for 1 year consumes 8.7kwh).

Well, if that is the case then the OP (or tenant) is better off as it is now; 1 or 2W LED lamp only being left on sometimes.

 

[Flipjango]

Thank you @Colin Brenton that was exactly what I needed. Took all of two minutes and is working perfectly now.