Removing the siren box from the wall

I need to remove the external alarm box/siren for maintenance of the wall to which its attached.

Presumably if I use the engineer code, switch off the mains to the panel and remove the control panel battery I will be OK?
The battery in the siren box, if any, is fifteen years old and hopefully long dead.

Alarm is a Scantronic 9452, I don't know the make of the siren.

And I guess when I put it back I'll need to do a tamper reset?

Thankyou.

Take a picture of bellbox and post it.

Bellboxs come in many diffrent forms, but all that have back up batteries even if disonnected from panel may sound depending on how they are set up.

Here's the box.




Dates from 2005.

Lucky if it’s even a working siren with ADT

So I removed the battery from the control panel, then turned the power off... and the external siren starts up. Arrrgh.
After 16 years the d..d battery is still good.

Took off the cover, did what I needed to the wall, put it back.
Was tempted to start pulling the wires, next time I'll make a diagram so I can.

We also have a Master Blaster on another wall, after half a minute that starts up, the cat goes apeshit and neighbours from 300yds up the lane come to investigate.
Should have turned the power off again or just killed it with the user code but I had ear defenders and didn't hear the din, oh dear.

I'll need to do more work on the wall, so to be continued next year.