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[email protected] timothy.w.oleary@verizon.net is offline
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Default 12v smoke, heat and CO alarms, with volt free contacts

Heat detectors do not require any power in order to operate. Just a
pair of wires back to the appropriate hard-wired zone terminals in the
panel. They are N.O. (normally open) devices; that is, they have
outputs which are open cicuit until actuated, then the circuit closes.
The alarm panel would hopefully call for the use of end-of-line
resisters on the zone loop wiring, and would accept either a closed
loop sensor or an open loop sensor.
The wiring of an open loop sensor would be slightly different than for
a closed loop sensor.

You would also need to ascertain if your panel is able to produice an
alarm condition upon either an open circuit or a closed circuit with
the end-of-line resister wired in the loop. Since I do not know what
systems are used across the pond, I cannot make any assumptions about
what y'all have. Some panels will treat an open as a 'trouble'
condition and not produce an alarm condition.

CO detectors are another story. The technology for those is totally
different than that required for a smoke detector, and the demand for
them has been limited.
PAMA has offered a unit for several years that will work off of 12VDC
which is what the typical burg panel has. General Electric Security is
advertising one in the trades, but I haven't seen one yet.
Kidde also offers several types. Marcuro is another brand I know of..

Similarly there is not a great selection of battery operated CO's that
have a "dry contact output" which is what you would use to connect a
detector to a hard-wired alarm panel, or use in conjunction with a
supervised wireless transmitter if you ware wanting to add a CO
detector to a professional wireless alarm system.
Most CO detectors are stand alone, and have integral audible sounders.
It is unlikely that you would want the fire department to respond if
you had excessive CO in your premises. So why would you want to connect
it to the alarm panel? Of course I could imagine several scenarios:
you're hearing impaired, it's a large struture and you might not hear
the alarm if it were to go off; it's a summer cottage, and you just
want to be notified. All good reasons. Changing batteries is a pain in
the butt so you'd like to power it off a constant voltage source.
Whatever the reason "The customer is always right"

BTW why do they call you 'sparks?'

email me of you need more info or post it on the forum; hopefully I'll
be notified.
hope this helps

Sparks wrote:
"SantaUK" wrote in message
...
I'll need to check my catalouge, but you can get a "normal" fire alarm
base unit that has relay contacts on it, and can put any of the heads,
smoke, heat or CO2 onto it. I can't recall the name but I will find out.


Thanks, that would be appreciated :-)

Sparks...