din rail timer, light switch override for outside lights

[ianbrookes]

I am looking for honest advice. I am a newbie but fully qualified domestic installer but have never done this install before.

I have an MK timer switch MK 5731s (din rail mount) an MCB for outside lighting (with RCD protection).

for cables I have a three core + earth running from the CU to the switch and an 1.5mm SWA 3 core running from the switch to the lighting transformer.

the customer wants the switch to override the time when required.

I am looking for wiring advice please.

 

[DurhamSparky]

badda bing badda BANG!!

draw a LINE diagram which you will have been taught on electrician course to decipher what route the current will "flow" then add your override to bypass the timer...! simples...!

line diagrams for lights and timers are first year stuff..!

 

[ianbrookes]

ego issue....

 

[Edd]

I have to agree with what Durhamsparky says, a drawing should make sence straight away..

But the forum is about help and advice so here goes
Forget the earths you know what to do with them!!
The 3 core from the CU you want to take a neutral, a permant feed (straight from the rcbo) and a feed from the rcbo through the timeclock.. thats the 3 cores...
Them at the switch, the cable you sent through the timeclock conect straight to the line conductor of the swa, this will only become live when the timeclock kicks in..
the same with the neutral connect to the swa...
The permant feed send through the switch..
and off to the same conector you conected the timeclock feed too. switching the switch on sends a permant feed down the swa.. (and back feeds the time clock but dont worry about that!)
hope that makes sence!!

edit forgot too add dont forget to take a neutral too your timer otherwise it just aint gona work

 

[ackbarthestar]

The last time I did one of these I used a DP contactor controlled by a remote wireless switch, then used a double pole override switch to energize both phase and neutral bypassing the contactor.

Remember that a time switch is what it says and all switches are placed in series with the loads, to override the time switch you need to place the override in parallel with the time switch but in series with the load.

 

[Edd]

I have to agree with what Durhamsparky says, a drawing should make sence straight away..

But the forum is about help and advice so here goes
Forget the earths you know what to do with them!!
The 3 core from the CU you want to take a neutral, a permant feed (straight from the rcbo) and a feed from the rcbo through the timeclock.. thats the 3 cores...
Them at the switch, the cable you sent through the timeclock conect straight to the line conductor of the swa, this will only become live when the timeclock kicks in..
the same with the neutral connect to the swa...
The permant feed send through the switch..
and off to the same conector you conected the timeclock feed too. switching the switch on sends a permant feed down the swa.. (and back feeds the time clock but dont worry about that!)
hope that makes sence!!

edit forgot too add dont forget to take a neutral too your timer otherwise it just aint gona work

Just looked at this clock it looks like you need to take a feed from your mcd to pin 1 and a neutral to pin 2. and also link between pin 1 and 4.. with your 3 core then take a neutral a permant fed and a core from pin 3.. ( no responsibility if the thing blows up)
then carry on with what I typed before..
But as has been said try drawing and thinking about it as you will learn it better that way..

 

[ianbrookes]

thanks again. I just don't see now how the switch can be used for permanent "off" when the timer is operating. I can see how the timer will switch the lights "on" and how the switch itself can be used for "on" when the timer is not operating.

 

[Engineer54]

thanks again. I just don't see now how the switch can be used for permanent "off" when the timer is operating. I can see how the timer will switch the lights "on" and how the switch itself can be used for "on" when the timer is not operating.

Are you not incorporating a light switch into this circuit?? Although it's not specifically required, i always like to see a local (if you like) means of isolation for outside lighting, and in your case could be a DP light switch. But your right in one respect, few timers come with a 3 position switch (eg, ...load override on / timed / load override off) most will just have a 2 position switch of timed and override on...

 

[JamesBrownLive]

Does the customer want the overide switch to completely overide the timer, i.e. both on and off, or just for it to be able to switch off the lighting?

 

[ianbrookes]

override for both on and off is required..

 

[Engineer54]

Then your MK timer can't oblige you, But if as i earlier stated, you incorporate a local isolation switch, this would facilitate the 'Off'' override function. It will also be a means of isolation when maintenance or lamp renewal is performed on the outside light fitting!! This will be the easiest solution to your clients job remit!!

You may have a job finding a 3 position switched DIN rail mounted timer, they will be very few and far between. I may be wrong, but i've not seen many of them at all, and we use a hell of a lot of DB mounted timers on my projects...

 

[telectrix]

so you need the overide On switch in parallel with the timer and the Off switch in series with it ( after the timer)..2 switches

 

[Engineer54]

so you need the overide On switch in parallel with the timer and the Off switch in series with it ( after the timer)..2 switches

The override ''On'' switch will be incorporated on the timer, the local isolation switch (if he installs one) can serve as the override ''Off'' switch..

 

[telectrix]

The override ''On'' switch will be incorporated on the timer, the local isolation switch (if he installs one) can serve as the override ''Off'' switch..

agreed, but i was thinking on the lines of not having to go to the CU for switching.

 

[Engineer54]

agreed, but i was thinking on the lines of not having to go to the CU for switching.

Yep, very true and a worthwhile consideration for the OP to think about Tel...