INSTALLATION INSTRUCTIONS
DOOR MONITOR DM1
Introduction
The DM1 processes and displays the status of up to eight circuits. The actual number of
processed circuits may be programmed by the engineer during installation. A set input is
used to determine the response of the unit to the state of the inputs. Two buzzers are
provided which sound to give an audible indication when the inputs do not correspond to the
normal condition. Provision is made to extend the buzzer to a remote position.
Each of the inputs are additionally monitored using 2K2 resistors for open circuit and short
circuit fault conditions.
A relay with a clean set of contacts is available for monitoring the sum of the inputs.
Additionally a clean set of contacts are provided from a tamper switch.
Operation
The number of circuits to be monitored is determined by a link placed in the program header
(see diagram). When placed in position 8 all inputs are enabled. Position 7 will monitor only
inputs 1 to 7, position 6 will monitor circuits 1 to 6 and so on.
The status of the system is
determined by the set input. When
open circuit the system is set (night
mode) and when closed circuit the
system is considered to be open
(day mode).
Each circuit is terminated with a
2K2 end of line device and the door
contacts (which are open when the
door is open) should be fitted with a
2K2 resistor in parallel.
In day mode the LEDs are enabled and display the current status of the inputs, green
indicating door open and red either door closed or fault (i.e. line open circuit or closed
circuit). All circuits which have been de-activated on the program header will always display
red irrespective of their status. The buzzers will sound if any of the enabled circuits are either
in fault or if the door is closed.
Once a set signal is detected, the
buzzer will sound if any of the inputs
are in fault (open circuit or short circuit)
or if the door is open. As soon as all
circuits are clear the buzzers will be
disabled until the set input goes open
circuit at which time it will respond as in
day mode. At the same time the LEDs
will be extinguished and will remain so
until the set input opens again.
The relay is normally energised and will release whenever one or more of the enabled door
circuits indicates open irrespective of the condition on the set input. Additionally the relay will
release if any circuit goes into fault when the system is set.
CIRCUIT INPUTS
PROGRAM HEADER
TAMPER SWITCH
1 8
