Buzzing Lighting Contactor

I've read a few threads on this, some inconstancy, if someone could help / advise

Moved into the house about 2 years ago, it has 2 spotlights out the front, as well as some standard outdoor lights doted around the place.
The standard outdoor lights look like they've been there since the house was built (~1985)

One spotlight looks like it completely replaced one of the older outdoor lights, and the other is looped off one of the older outdoor lights.

There are 4 sensors at each corner of the house that when activated turn on all of the lights, spots and older lights.


At the fuse board, there is one of those string switches you have sometimes with electric showers, pulling this and I hear a loud click and the spotlights come on for a couple of minutes, then another click and they're off.

There is also an intermittent buzzing sound at the board, not always there.

So I did some investigating and found the source of the click and the buzzing sound: contactor


It appears that the relay / contactor above is wired to the spotlight motion detractors, and that when they are activated they send a signal to the above relay which switches into the on position (the click) and activates all the lights.


Does that all sound plausible

The buzzing sound coming from the contactor, it can be temporarily silenced when I wiggle it (sometimes).

It is sometimes a much louder buzzing, that only last for a couple of seconds / minutes, and only seems to happen intermittently, when I pull the string switch into the off position.

My questions are these:

1. Does it sound like the contactor needs to be replaced, or is debris / rust the cause, and fixable, by re-seating / cleaning the contactor?
   
   
2. If I need to change the contactor, I've read about solid state, should I replace with something like that, or a like for like replacement?
   
   
3. I want to replace the string switch with something automatable, that I can set on a timer, and / or activate remotely from my phone / Alexa, suggestions?
   
   
4. The string switch setup seems strange to me, very hacky, the cables in it are both brown, no neutral or earth, is this normal / acceptable, does it limit what kind of switch I can replace it with?
   
   
5. If I leave the string switch in the on position all the time, the lights only come on at night, because of the settings on the motion detectors, but is having it on like this constantly wasting a lot of energy, is there a better way of setting this up that wont break the bank?

Any help / advise on this would be really appreciated, need something to keep my occupied or I'll loose my mind :rolleyes:

Bruthal

Contactors can be used by sensors bringing on lights, especially when the same lights can also be switched individually or in groups by separate wall light switches.

The buzzing might be caused by dirty or rusted contactor core pole faces, the non smooth surfaces now chatter as the AC voltage passes 0v 100 times a second. The fact you can stop the buzzing by moving the core a little suggests this is the cause.

Cleaning or replacing can fix.

Solid state contactors should work well if preferred, although the existing contactor may have multi pole contacts and may be more suitable if it is switching using several poles.

For alternative control instead of the pull switch, a sonoff relay might work well. They can be controlled via phone app, timers set, sunrise/sunset etc.

Bruthal

Bruthal wrote: »

Contactors can be used by sensors bringing on lights, especially when the same lights can also be switched individually or in groups by separate wall light switches.

The buzzing might be caused by dirty or rusted contactor core pole faces, the non smooth surfaces now chatter as the AC voltage passes 0v 100 times a second. The fact you can stop the buzzing by moving the core a little suggests this is the cause.

Cleaning or replacing can fix.

Solid state contactors should work well if preferred, although the existing contactor may have multi pole contacts and may be more suitable if it is switching using several poles.

For alternative control instead of the pull switch, a sonoff relay might work well. They can be controlled via phone app, timers set, sunrise/sunset etc.

Thanks for the reply, I might just replace it with a like for like so, no harm I suppose.

I'll check out the sonoff relay, thank you again.

Steve

Before you replace it , while it's de-energised, give it a good solid whack or two with something heavy. Not to break it but to dislodge the bit of dirt inside the armature. This is normally the cause of buzzing. 30+ years of experience, your call whether to try it..

Steve

Steve wrote: »

Before you replace it , while it's de-energised, give it a good solid whack or two with something heavy. Not to break it but to dislodge the bit of dirt inside the armature. This is normally the cause of buzzing. 30+ years of experience, your call whether to try it..

I'll give it a bash, pun intended :pac: