I want to use 12volt bells as my warning devices but I've been told that they will burn out the microprocessors on modern control panels. Is this just a way for the trade installer to put me off doing it myself or is there any truth in what he's saying.

Motorised bells should be ok. But yes he is correct. Solenoid bells can create large 'back emf' that will damage the control panel.

 

It can be done but the bell needs to be isolated from the control panel. You will also then need to protect the dedicated psu used to drive it.

Its cheaper and better to use a modern electronic sounder unit, unless you have a real need for it then id avoid.

 

James

I also agree.

 

Most if not all intruder alarm panels have the facility of an internal speaker (16ohm) that can produce an electronic siren sound along with entry/exit tones etc..

 

If you require a 'bell' sound there are some electronic sounders that can have a specific 'bell' tone... These are more commonly used for fire alarm applications and the bell sound is used for classchange in a school (my high school uses this feature) or a panic alarm in a bank

 

The range of external sounders for intruder alarms are much more reliable compared to a bell and have a much much louder sound output and the facility of an integral strobe.