Two PIR sensors to work same lights

needsomeadvice · Feb 26, 2019

Hi all

Does anyone know of PIR sensors that can be connected to switch on the same lights.
Basically, i need to install 2 sensors located around the corner from each other and either of these two sensors need to switch on 4 led wall lights.
Spoke to Knightsbridge, they say that this can't be done as you would be sending a switched live back down to the other sensor that hasn't activated.

Has anyone installed PIR's like this without any issues? If so, what ones have you installed?

Thanks for any input.

buzzlightyear · Feb 26, 2019

two switches for both would do ,would the customer need to over ride them .

HappyHippyDad · Feb 26, 2019

I have done exactly the above with the standalone sensors from screwfix and they have been working fine for around 4 years now. They switch approx 10 x LED's going up a pathway.

[ElectriciansForums.net] Two PIR sensors to work same lights

telectrix · Feb 26, 2019

so what's wrong with sending a S/L to the other PIR. it won't explode.

TJ Anderson · Feb 26, 2019

needsomeadvice said:
Hi all

Does anyone know of PIR sensors that can be connected to switch on the same lights.
Basically, i need to install 2 sensors located around the corner from each other and either of these two sensors need to switch on 4 led wall lights.
Spoke to Knightsbridge, they say that this can't be done as you would be sending a switched live back down to the other sensor that hasn't activated.

Has anyone installed PIR's like this without any issues? If so, what ones have you installed?

Thanks for any input.

As long as the total load of lights does not exceed the switched rating of one of the PIR'S then there is no problem in paralleling the outputs from them.

TJ Anderson · Feb 26, 2019

happyhippydad said:
I have done exactly the above with the standalone sensors from screwfix and they have been working fine for around 4 years now. They switch approx 10 x LED's going up a pathway.
View attachment 48040

Hi HHH. Am I reading your drawing correct? It looks like your timer output is in parralel with your PIR outputs. Is that what you wanted? PIR operation with a timed override?

HappyHippyDad · Feb 26, 2019

TJ Anderson said:
Hi HHH. Am I reading your drawing correct? It looks like your timer output is in parralel with your PIR outputs. Is that what you wanted? PIR operation with a timed override?

The customer wanted them to come on at a certain time in the evening and then switch off, but also wanted them to be constantly (at night) on a PIR from top of drive and bottom of drive.

Loki · Feb 26, 2019

A quick search found this

SparkyChick · Feb 26, 2019

I know Luxomat sensors are quite happy having power fed into the switched live output.

Depending on the area you are covering though, you can get corner sensors that look all around.

DefyG · Feb 26, 2019

Nothing wrong with that unless Knightsbridge are suggesting the 'inrush current' maybe a problem and not because of sending a s/l back to the other sensor.
When they start 'playing up', (they invariably do!), you get the ladder up to investigate the sensor and it will always be the other one!

Blissof89 · Feb 27, 2019

telectrix said:
so what's wrong with sending a S/L to the other PIR. it won't explode.

I have installed some pir floods before that didn't play well together, they were suppose to share a SW live so they could turn each other on but they would flash repeatedly when ''back feeding' each other.

I have no idea what caused it but I'm going to take a stab in the dark and say back feeding the SW live side of PCB makes a relay chatter.

MFS Electrical · Feb 27, 2019

telectrix said:
so what's wrong with sending a S/L to the other PIR. it won't explode.

Unless it’s on another phase

Marvo · Feb 27, 2019

Blissof89 said:
I have installed some pir floods before that didn't play well together, they were suppose to share a SW live so they could turn each other on but they would flash repeatedly when ''back feeding' each other.

I have no idea what caused it but I'm going to take a stab in the dark and say back feeding the SW live side of PCB makes a relay chatter.

Probably a solid state switch on the output rather than a relay.

TJ Anderson · Feb 28, 2019

happyhippydad said:
The customer wanted them to come on at a certain time in the evening and then switch off, but also wanted them to be constantly (at night) on a PIR from top of drive and bottom of drive.

I see

ackbarthestar · Mar 1, 2019

Yes, I have three of them on one circuit around the house controlling six LED 15W wall lights. I also have an overide switch for manual operation, never needed to use it as the misses doesn't spend too much time collecting firewood from the shed.
They have been up and running without incident for the last 2 years.