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There are a number of control routines. They are all achieved with had wiring, relays, some timers, and the odd diode, or simple logic circuits. Control routines are achieved using both low voltage (12Vdc) and mains voltage (230Vac). Where there needs to be interfacing between the two voltage schemes, this is done within the mains voltage enclosures.
Here is a list of control routines and features. There is so much involved within the system, that some may be missed out. In addition, there are so many interconnections, and dual usage items, that some of this may become complicated.
1) A dawn dusk switch is fitted, which has various sub routines.
1A) It will pulse the hall landing and stairs lighting stepping relays, if the lights are off. If the lights remain on another time clock will step them off, at an appropriate time, at the end of the evening.
1B) Curtains in the lounge and the bedroom, are closed, if they are open (they usually are!) The curtains in the lounge re-open automatically at dawn, whilst the curtains in the bedroom, are opened manually, when I get up. When the curtains are closed in the lounge a table light is switched on, so that I'm not left in darkness. This is switched off by a timeclock, late in the evening.
1C) A path is prepared to bring on lights if the appropriate doors are opened, or a fire call occurs.
1C1) On a fire call, lights in the bedroom, the landing stairs and hall, the kitchen, and outside lights are triggered. these are timed to go back off, after approximately 2 minutes.
1C2) On opening the back door, the outside lights are turned on, they stay on for a couple of minutes after the door is closed.
1C3) On opening the outer front door, the porch light is switched on, for approximately 2 minutes. Opening the inner front door also triggers this light.
1C4) On opening the inner front door the hall stepping relay is triggered, switching on the hall lights.
There are two distinct phases of a fire call, alert, and shutdown. On alert, the alarm is raised, and if at home I would start to respond, when I do respond I automatically trigger the "shutdown" section, which triggers a number of devices. This is another use of the contact on the doors, hence outer door opening during an alert, triggers shutdown.
2) On Alert.
2A) Central heating shuts down.
2B) Gas fire shuts down
2C) Gas cooker shuts down
2D) Power to "Fire Call Shutdown" sockets, both workshops, and outside sockets is shut down.
2E) Stereo is shut down.
3) On Shutdown,
3A) The second answering machine is switched onto the telephone line, telling people who know me, that I am unavailable, due to a fire call.
3B) The television is switched off.
3C) The computer is switched off.
3D) The coded keypad on the front door is enabled, allowing friends and relatives arriving at my house, to let themselves in.
3E) A small discreet blue indicator lights, warning people, who know where to look, that I am out on a fire call.
4) The contact on the doors and locks are wired to a number of a number of LED's on a mimic panel in my bedroom, which warn me, if a door is insecure, or anything else is "off normal"
5) The door contacts feed into a single discreet red LED placed by the front door, which warns me if the house is not locked up tight, as I go out.
6) Operation of the door bell, the outside flood light, or opening either of the front doors will power up the video camera over the front door, which feeds into the main aerial cable down feed, such that any television in the house can be switched to look at the guest at the front door. ( if they have Jehovers Witnesses written all over them, you don't have to get up to go to the front door!!!)
7) A contact on the letter box, lights an LED on the bedroom mimic panel, telling me that post has been delivered. The LED is held on my a latch up SCR, which is reset on opening the front door, which I would have to do to collect the post.
8) There are a large number of phones around the house, and they are all connected to the line. This would give major problems with the REN being exceeded. I have concocted a ring switch system, which is hooked into the security system. When an internal PIR is triggered it resets the last relay, and operates the relay appropriate for the room. The "ring" wire for the phones in the room, are fed via this box, hence only the phone in the room which is occupied will ring, when there is a phone call.
9) The extractor fan in the bathroom is delayed from operating by a timer, once the timer has operated and pulled in the fan, the fan will run for a minimum of ten or so minutes. The fan is initially triggered by the light being switched on, but the light has to remain on for a few minutes to pull in the fan. It can be seen that if the bathroom is occupied for a short period of time, the fan will stay off (unnecessary, when it is only used for a quick hand wash, or a leak!) However, if the room is used for a longer time, A bath, shower, or other smelly activity, the fan will be required. A heat sensor on the shower will also start the fan if the shower is used, without turning on the light. Under these circumstances the "run on" timer is still used.
10) A redundant 386 computer is used to radio-page required announcements to me, when I am away from home. It is a simple system, sending simple DTMF to the paging bureau, giving me a coded numerical message to inform me of one of four events which will trigger the machine.
10A) A message having been left on my "normal" answering machine
10B) A fire call coming in.
10C) Post having been delivered.
10D) The security system being triggered.
10E) In addition to paging me, the computer gives me a print out of the time and date of the event..