What about Aplex the lems are inside the detectors with the bus running round the detectors therefor the signals are on the bus line. I assume that that meets grade 4 ??

Grade 4 isnt just about signalling but its biggie is that it must offer 'range reduction detection' is if the area of coverage chnages massivly it should be alerted. Thats why AFAIK the siemans (old alarmcom) unit uses a camera and you program it to the room. It compares the image stored with the current image.... big partition in the way = alert

Grade 4 isnt just about signalling but its biggie is that it must offer 'range reduction detection' is if the area of coverage chnages massivly it should be alerted. Thats why AFAIK the siemans (old alarmcom) unit uses a camera and you program it to the room. It compares the image stored with the current image.... big partition in the way = alert

Only works with the light in the room on, Doh!! (but their working on it)

lol, IR I assume?

you would think that microwave or ultrasonic could learn the environment its in, ie bats, dolphins and whales manage fine.