Pir for fridges

maxamillius

Are all pir's suitable for use in commercial cold rooms and freezers?presume they just need to be ip rated

frankmul

Just had a quick look at steinel outdoor pir. Only rated to -20 deg c. Freezer might go to -25

LeBash

I doubt they will work for a long period of time at those temps. Was asking a similar question myself recently and the manufacturer claimed it would need to be a specificed cold room pir even though they claim -20c also.

Also pir is not great in that enviroment. Generally the person in the cold store will be dressed in heavy jacket, trousers etc which will limit what the pir can see as they look for heat movement.

maxamillius

LeBash wrote: »

I doubt they will work for a long period of time at those temps. Was asking a similar question myself recently and the manufacturer claimed it would need to be a specificed cold room pir even though they claim -20c also.

Also pir is not great in that enviroment. Generally the person in the cold store will be dressed in heavy jacket, trousers etc which will limit what the pir can see as they look for heat movement.

Cheers for reply,think I'm just gonna go with a time delay switch outside,problem is people switching lights on in cold rooms and just leaving it on all day!

LeBash

maxamillius wrote: »

Cheers for reply,think I'm just gonna go with a time delay switch outside,problem is people switching lights on in cold rooms and just leaving it on all day!

Is it a large room? You could use a time switch set 9-5 or whatever tickles your fancy on just enough of the lighting to pass with healthy and for the others an Elpa with warning before switch off.

liveandnetural

most large commercial frezzers use low or high bay discharge fitting and dont like been switched on sensors
but it depends on what you have

http://www.wattstopper.com/products/sensors/ceiling-or-wall-mount-sensors/cb.aspx#.UuHL6funzGg

these work in -30 you need it the close to the door and switch the load tru a contator

another thing to watch for is the (run time or on time ) if someone is working inside in the freezer ie forklift driver picking orders you dont want the sensor to time out and leave him in the dark

sawdoubters

yes to -30

http://www.guardian-controls.com/pir-detector-lo-temp-white-pir-360-f_P215.html