Burgalar Alarm PIR Sensors 'churp'

Mutton_Geoff

Another suggestion is that the power supply is no longer 12v or is "contaminated" with some AC due to a PSU fault in the control box and the relays in the sensors are vibrating instead of opening/closing properly.

As it's happening on all your sensors, the problem must be common so points to a power supply issue. Put the control panel in engineer mode then with the cover off a sensor, use a DMM to measure first the DC voltage at the sensor then switch it to AC and see if there is any residual AC ripple on the +/- connectors. It should be zero but any PSU regulator fault may cause some AC to be present on top of the DC supply.

It's all I can think of as I don't know of any sensors like yours that have noise generating devices in them.

curlyfairy

Can you take the lid off the PIR so we can see the PCB please?Might be worth a look.
I have talked to many other alarm engineers and none of them of heard of a PIR that makes a noise.
I wonder if its the relay that opens when it detects movement?

Financial_Savvy

Financial_Savvy

Financial_Savvy

Guys I have uploaded some pics for you.

Look forward to any thought you may have. My financee told me to tell you all that the chirp is not very load, nothing like when the alarm is set to 'chime' however you can still hear it and it annoys the hell out of me!

curlyfairy

Hello again,a couple of things to try.

1-In the bottom left hand corner you can see the sensitivity jumper,take this off and then see if it makes the same noise as before.
2-As said before if you have a Multimeter put the probes across the red and black wires,the reading should be around 11-13volts dc.
3-Finally if you can disconnect the red wire from the pir so it is completely out,leave it 30 seconds and then put it back in,again see if it stops making the noise.

Let me know how you get on.

Here is a PDF of the PIR.
http://www.alertelectrical.com/upload/pdf/875is215t-ds.pdf

Ben.

Financial_Savvy

Hi, thanks very much I will try this. The manual suggests that you can enable/disable the LED. Do you know who I can do this as well?

curlyfairy

All you need to do to stop the led working is cut the link on the top lhs of the pcb just under the 2 yellow capacitors.Is it still making the noise whilst the lid is off?

Ben.

Financial_Savvy

Hi, I have had another look. I have removed the sensitivity jumper and in all possible options it still make the same noise.

I have disconnected the red wire (in block #1) and when it is removed it stops the PIR from working, but as soon as it is back it makes the same noise when the LED comes on.

Few things I have noticed.

1. Some PIR's make the noise more (louder) than others.
2. When I disconnected the red cable when I was putting it back, as the small wire would connect it would make the same chirping noise. If you held the cable on the outside of the block but on the metal part it would make the chirp noise almost constantly.

The cabling sequence looks like this

1. Red
2. Black
3. Blue
4. Yellow
5. Green
6. White

On one PIR the white and green cable were both in #5. I have the pic if you want this.

Not that I have a clue but it does seem like when the relay detects movement this makes the chirp noise.

I have found some more sensors on Ebay. Can these be replaced as a DIY job?

Thanks to all and Merry Christmas.

Financial_Savvy

Forget to say yes it still makes the noise when the lid is off.