pir

[hue-jarse]

HI all
First post on here so be gentle!
I want to connect a pir in my garage to switch off my 1.5kw compressor. Would your average home/diy pir do the job.

Many thanks
Jarse

 

[Paul.M]

Welcome to the forum.

Your a mechanical engineer and we assume you have an understanding of electrics???


1.5Kw load on a standard domestic PIR would not work. They are normally rated at 400-800w. You need a contactor set up and this is something that a DIYer should not attempt themselves.

 

[telectrix]

most PIRs that are intended for floodlight switching will handle up to 2500watts. it may be that the type of load ( i.e. inductive) is unsuitable. try one and see.

 

[Richard Burns]

Home PIRs also do not have the capacity to switch off loads, only on.

 

[telectrix]

missed "off". could be done using a latching N/C contactor.

 

[HandySparks]

HI all
First post on here so be gentle!
I want to connect a pir in my garage to switch off my 1.5kw compressor. Would your average home/diy pir do the job.

Many thanks
Jarse

So do you want the compressor to switch on or switch off when a person is detected?

 

[Marvo]

Rather look at occupancy sensors than a standard PIR motion sensor. You'd probably require a relay or contactor in the circuit between the sensor and the load to do the grunt work of switching the compressor which will be a highly inductive (AC3) load with a considerable starting current.