Changing PIR's - advice please

[teddyman5]

Having recently moved house I need to change some pir's as they have yellowed and got paint on them etc.We have redecorated so I need to replace them.Do I need to turn the power off?
How do I stop the alarm going off?
Wheres the cheapest place to get pir's?
Any and all advice very welcome.
Thanks in advance.

 

[Spark123]

Usually putting a panel into engineer mode will disable the tamper alarm when you remove the covers.
It is advisable to disconnect the 12v supply going out to the PIR in the panel before attempting to dismantle a PIR.
Do you have any information on the panel and the PIRs?

 

[teddyman5]

Usually putting a panel into engineer mode will disable the tamper alarm when you remove the covers.
It is advisable to disconnect the 12v supply going out to the PIR in the panel before attempting to dismantle a PIR.
Do you have any information on the panel and the PIRs?

Only info is that the panel is an Omnicron 8000