"Matty F" wrote in message
...
Does anyone have any brilliant ideas about how a security guard can be
notified when sensor lights turn on? The lights may be up to a mile
away so he can't necessarily see when they turn on.
The guard will be walking around, so there will have to be
notification via radio or cellphone or pager etc.
Ideally it would be helpful for him to know which lights went on.
When notified, he can go somewhere to look at a screen. Or he could
have a laptop computer using WiFi that can show whatever he needs to
see.
I was thinking that each sensor light could have a signal wire from
the supply to the bulb or from the relay, to a central point.
Complications are that he may set off sensor lights as he is walking
around, and cats etc may set them off. So, lots of false negatives
which he must be able to discount.

There are probably off-the-shelf solutions for this, but they are probably
expensive. If you want to avoid false alarms de-sensitizing the costly
security guard, it might be worth spending money on these.

When I wanted to do something similar, I took the DIY approach of using IQ
PIR-controlled lights, which send a radio signal to a nearby ( 100 metres)
receiver when activated. It's fairly straightforward to interface the
receiver to the serial port of a PC which can send emails to the security
guard. Screwfix have stopped selling them, but these look similar:
http://www.tlc-direct.co.uk/Main_Ind...ems/index.html

Another cheap DIY approach might be to install a CurrentCost power monitor
on the incoming supply to the monitored building. These can be interfaced to
a PC's serial port, and some software could be written so that when the
consumption jumps by a suitable increment (150W, 500W ?) for more than a few
samples, an email is sent.