Why does external light keep coming on?

[glassescase]

I have 5 external lights, all fitted with their own PIR sensor.
3 do not have bulbs in, possibly because they kept coming on, I can not remember. 1 seems to only come on when I move in front of it.
This leaves 1, I have covered up the sensor with tape, I have covered up the 3 other sensors where bulbs are not fitted with tape and still at night, I have this one light coming on. It goes off for a few seconds and then comes back on.

I am bewildered how this can happen, have you any ideas?
A possibility is that there is another perhaps in a loft, PIR light or just a PIR and that PIR is triggering all the others or at least this 1 that I am having a problem with.

I think there re two adjustors on each light but as the sensors are covered up, I would not have thought they do anything except perhaps control how long the light is on for but not if it comes on.

I cant think how these lights could be wired for this situation to arise, can you?

cheers

glassescase

[Scotty001]

Could it be the lux and sensitivity controls are set In a way that the light is permenantly active (especially if you have the sensor covered) , the pir will think it's pitch black all the time, and the sensitivity turned to max would mean the light comes on and stays on for a period of time based on the lux reading?

[glassescase]

Could it be the lux and sensitivity controls are set In a way that the light is permenantly active (especially if you have the sensor covered) , the pir will think it's pitch black all the time, and the sensitivity turned to max would mean the light comes on and stays on for a period of time based on the lux reading?

I will check what you say. I have only covered the sensors tonight in an attempt to stop the light coming on. The bush in front of the light has been pruned to within an inch of it's life but I now don't think the bush is the problem.

I thought if the sensor could not see movement the light should never come on.

glassescase

[Someone-Else]

I thought if the sensor could not see movement the light should never come on.

That is correct.

I suspect either your PIRs are failing or they are picking up mains spikes.

[ericmark]

PIR lamps can have three adjustments, time on, sensitivity, and daylight off level, but not all have the controls, they should detect inferred changes, so theroy a moving bush or tree should not affect them, but be it due to masking some inferred source or some thing else, I know trees moving in the wind can set them off.

I have played around with insulation tape masking some areas or reducing the light and have had some success, but where I use to live the outside lights were not really required, I could see enough with the street lights, just nicer to have a little extra light, but this house, the outside lighting is relied on, without it need to use light on my phone to see way to main door. So the last thing I want is half way up the path with hands full of shopping for the outside lights to switch off.

So in the main I have swapped to smart lighting, 8 outside lights, 6 being smart, some smart bulbs, some smart switches, and some smart socket adaptors. Also some rooms with smart light switches so can turn on room lights to help light outside.

I did try solar powered lights, but they do not seem to last, each year we seem to be replacing them.

[Someone-Else]

So in the main I have swapped to smart lighting, 8 outside lights, 6 being smart, some smart bulbs, some smart switches, and some smart socket adaptors. Also some rooms with smart light switches so can turn on room lights to help light outside.

I did try solar powered lights, but they do not seem to last, each year we seem to be replacing them.

............I am trying to understand how telling glassecase what you had and what you did helps him?

[glassescase]

Hi guys what do you think of this, has just talking and thinking cracked it?
Just had an idea I put to my wife. My idea that I put to my wife. The lights have been wired to bypass the motion detection and only detect night and day.
Wifes response, does that mean by covering up the sensor the light thinks its night time all the time and is now (in the day) on?

just been outside to check and hay presto, the effing light is on.

Guessing the timer for how long the light is on for is working hence the cycle of on ad off all the time. :)

I will have a light off and see how it is and perhaps others are wired.

glassescase

[dewaltdisney]

I think the PIR's have a life and I have experienced my garage light being triggered by the slightest motion and conversely I had another one where you had to be right under it to activate the light. The best one I have is a cheap motion-sensing porch light bulb. This cheap Chinese bulb has been in use for 7 years now and works perfectly.

DWD

[Someone-Else]

The lights have been wired to bypass the motion detection and only detect night and day.

Doesn't sound right.

A standalone mains PIR has an internal light sensor, so that the PIR will only switch when it sees movement and the light level is low (dark)
You have said you have a PIR, you haven't said you have a separate light sensor, so how can they only sense night and day if they have been by passed?

[glassescase]

The lights have been wired to bypass the motion detection and only detect night and day.

Doesn't sound right.

A standalone mains PIR has an internal light sensor, so that the PIR will only switch when it sees movement and the light level is low (dark)
You have said you have a PIR, you haven't said you have a separate light sensor, so how can they only sense night and day if they have been by passed?

sorry if I have caused confusion, the pir is part of the light. I dont know the answer to your question. I will have to prove which "fuse" relates to the light that is in a cycle of on ad off and disconnect the power to that light. Once done I'll take the light off the wall and look at the wiring.
I'll report what I find

glassescase

[glassescase]

I have had the light off that keeps coming on. The only thing I am unsure about is that the light has 2 neutrals and they were both connected to the mains supply neutral. Apart from that I don't think there is an issue with the wiring. I have however connected up an ordinary light to see if that ever comes on, this will prove nothing else is effecting the light. I am pretty sure now there is nothing else involved.

dewaltdisney may be right with the sensors having a life span and as these are cheap lights he could be right.
One sensor looked to be set to minimum and the other to a mid setting.

I will wire this light to a 3 pin plug and play around to see what else I can discover.

Thank you for your help, it is appreciated.

glassescase

[dewaltdisney]

GC I think you need to evaluate the need for the lights and replace the crucial ones. They may be so old that they do not have cheaper to run LED lamps and as new exterior lamps complete can be had for around £17 from Screwfix it might make economic sense to review your installation to future proof it.

DWD

[glassescase]

GC I think you need to evaluate the need for the lights and replace the crucial ones. They may be so old that they do not have cheaper to run LED lamps and as new exterior lamps complete can be had for around £17 from Screwfix it might make economic sense to review your installation to future proof it.

DWD

thanks, they do seem to have LED bulbs. You seem to be right about faulty sensors. I wired the light to a 3 pin plug and left it in a dark room and it has been going on and off. I've never experienced such a fault, I live and learn, thank you. It would be nice to have lights come on as we approach, the problem being there are shrubs, bushes and flowers that may be seen by the sensor.
I have also found out that not all the external lights are controlled by the same "fuse" at the "fuse" box. This light is on the same circuit as the internal porch light and dining room light, no other internal lights seem to be on this circuit. At least one other external light is on a different circuit.
Lets not worry, the house came with an electrical safety certificate.

glassescase