RCBO tripping with PIRs

[wolfboy]

Hi been to test a job today which our company has wired.Have got a lighting circuit with a PIR contolling lights with an override switch.When lights overriden work ok,when through PIR RCBO makes a clicking noise as soon as PIR switches but the lights stay on for about an hour before tripping.Override switch is wired so that PIR supply is isolated feed to PIR meggered ok.Any suggestions?

 

[Spudnik]

Sounds like a possible faulty PIR.

If its a stand alone sensor, then swap it out for a new one and see if the fault clears.

 

[wolfboy]

tried two other RCBOs both click but dont trip straight away.tried a different PIR!

 

[Spudnik]

hmmm.

How about the light fittings?

What type of lamp are they?

 

[wolfboy]

pl 4 pin x2 per fitting, 12 fittings in total, but dont trip when switch to override!

 

[Spudnik]

Just a long shot, but is the PIR rated for CFL's?

I know some will not take flourescent loadings and ones that do, are quite low.

 

[wolfboy]

other rooms in building same lights same PIRs same RCBOs working ok so bit of a nightmare