Scantronic 500r+ Control Panel Noise Problem

[ianmac57]

I installed a Scantronic 500r+ wireless control panel + PIR's probably 15 to 20 years ago. I have a AG6 external bell + strobe unit hard wired.
The system has worked reliably since day one then about a month ago the bell + strobe unit started making more frequent cheeping noises (like very loud magpies). I tried to solve the problem by trying various tests but finally figured out that the AG6 tamper switch had become faulty. I bought a replacement Honeywell AG6 from Amazon and installed - easy, until 2 days later the Scantronic control panel has stated making a low droning noise from the loudspeaker. There is no 'fault' registered in the system but I have had to temporarily disable the whole system by opening the control panel door.
It seems too much like a coincidence that I replace the AG6 bell + strobe and very soon after the control unit speaker starts acting up - as if its picking up a feedback signal from somewhere.
I've tried Cooper Scantronic but you need to get past the registered installer code system ........
I would appreciate any suggestions.
Many thanks

Ian MacKenzie

 

[Hoover]

so if you disconnect the bell from the panel there panel speaker behaves okay?

it does sound like feedback and probably need a diode to stop it but I don't understand why the replacement bell is giving you feed back as you've replaced it like for like.

I am guessing the bells changed a little over the 20 years mind.

 

[sparkymarka]

By the way the chirping noise will probably be the nicad flat/faulty in the bell box I've heard the ag bell boxes doing this when the nicad is flat.

 

[ianmac57]

Hoover - yes, disconnecting the bell+strobe unit from the control panel results in the panel speaker behaving properly.
(The bell+strobe 'power tamper' trips and activates the bell).

The AG6 bell+strobe has changed - not very noticeably but now the unit has 2 red LEDs which flash all the time to alert that bell+strobe unit is live. Other than that there are no obvious physical changes.

Sparkymarka - yes, I had read on a forum that the chirping could be down to the bell+strobe battery - obviously I have had the unit way in excess of the 2 - 3 year life which may be expected. However, I could simulate the chirping noises by twiddling the tamper switch contacts which led me to believe that was the problem.

After your posts I went through some more tests and found that disconnecting the control panel battery connector silenced the panel speaker. I would have thought that if the panel battery was failing then a proper alarm would show on the control panel ??

 

[sparkymarka]

How old is the battery ? More than 5 years replace it.

 

[Europlex]

How old is the battery ? More than 5 years replace it.

 

[Hoover]

On many panels you may get an alert visible or audible warnjng but not an alarm as such when theres problems with batteries or mains.

Many manufacturers would say replace the battery after 3 years as routine but most wait till the system fails.

Quite common to get lots of calls after power cuts in an area when people have old batteries.

 

[Europlex]

Yuasa told me that 5yrs should be no problem, they should know.

 

[Europlex]

But I've replaced many at 1, 2, 3, 4, & 5yrs.

 

[Europlex]

But, there again that's what the IBT is for. (Intelligent Battery Tester)

 

[sparkymarka]

Is a uk made yuasa or a ting tong wing Wong yuasa ? Lol just had a box of 2.8ah all at 0.80 ah, alarm panel says battery fault....... Ok with the uk made battery.....

 

[Hoover]

I meant alarm manufacturers not battery manufacturers

Personally I know some that have batteries lasting longer and some much much shorter where they have problems with mains supplies(isolated rurals).

There can be many factors which can shorten the battery life.

 

[Europlex]

Oh for the day that, EVERYTHING, that is manufactured works 100%.

Do you think that will ever happen?

 

[Hoover]

Pmsl

We can but hope but doubt I will see it in the next decade for sure

 

[ianmac57]

Sparkymarka - have replaced the control panel battery and now glorious silence.
Well at least I got my money's worth out of that battery (Challenger AA51 - replaced with AA61 - guy at CEF had never seen an AA51 before !! and he didn't look too young !!).

Folks - thanks for your assistance !