Hi, I have a wireless (433MHz) alarm system. The PIR sensors this came with are prone to false triggering.
The alarm manufacturer does not supply any active IR sensors that are compatible, however I do have the technical know-how to buy an active transmitter/receiver pair and link it to a spare wireless sender, thus triggering an alarm. I am aware that the active setup requires a permanent power source - I can sort that via a mains adaptor.
I am wondering what might happen though if the mains power failed. In the milliseconds before it died completely, I would need the active IR device to intelligently realise that the reason it wasn't seeing a beam any more was because the power has just gone off, and not because the beam has been broken by an intruder. I would need it to maintain a 'Normally Closed' output condition throughout, up to and including when the power came back on again.
I am capable of designing a circuit that would sense a power fail and kill the power to the wireless sender first, so if the IR detector then went open cct it wouldn't matter because the alarm signal would never get transmitted to the control box. But that would be a whole extra level of complexity.
Also, is anyone aware of an active IR sender/receiver in a single box that you use with a corresonding mirror? Otherwise I need power going to two boxes - sender and receiver.
Thank you.
The alarm manufacturer does not supply any active IR sensors that are compatible, however I do have the technical know-how to buy an active transmitter/receiver pair and link it to a spare wireless sender, thus triggering an alarm. I am aware that the active setup requires a permanent power source - I can sort that via a mains adaptor.
I am wondering what might happen though if the mains power failed. In the milliseconds before it died completely, I would need the active IR device to intelligently realise that the reason it wasn't seeing a beam any more was because the power has just gone off, and not because the beam has been broken by an intruder. I would need it to maintain a 'Normally Closed' output condition throughout, up to and including when the power came back on again.
I am capable of designing a circuit that would sense a power fail and kill the power to the wireless sender first, so if the IR detector then went open cct it wouldn't matter because the alarm signal would never get transmitted to the control box. But that would be a whole extra level of complexity.
Also, is anyone aware of an active IR sender/receiver in a single box that you use with a corresonding mirror? Otherwise I need power going to two boxes - sender and receiver.
Thank you.