Securitron DPA_Series - Manual (Page 5)

PN# 500-15700
Page 5 Rev. C, 04/11
closing or resecuring the door. The act of doing this will send a +V reset input to RS and reset
will be accomplished automatically.
It's worth noting that wiring for auto reset has an effect on forbidden condition detection. When
you have made connections to both lock status and door status signals, a forbidden condition
alarm will be given instantly if, at any time, the door reads open while the lock reads secure.
The condition will reset itself immediately when the door recloses as lock status and reset are
tied together and are both continuously sending +V to their respective inputs. To summarize,
when auto reset is wired, a forbidden condition alarm also auto resets.
7. BYPASS AND DURESS
These are strictly optional functions. The DPA will be bypassed when +V is input to terminal BP.
As long as this connection is maintained, the board will retain its relays in the normal state and
will ignore all other inputs. Note that bypass can only be accomplished when the DPA is
in the normal or authorized condition. Bypass cannot be used to terminate other alarm
functions in progress. Duress and forbidden condition detection also operate while the
board is bypassed, as responding to these events is vital for security.
The purpose for bypass is to deactivate the DPA during times when the door can be propped.
This is usually a time of day issue and the bypass input can be activated by a time clock signal.
A question that is sometimes raised is why not simply unpower the board to take it out of
service. This will not work because relay #3 is in a normally energized state and when power is
removed to the DPA, it will deenergize which will be read as an alarm signal.
Duress is an optional instant alarm function. When +V is momentarily input to terminal FE, all
three relays begin to pulse every three seconds. A duress signal will always override any
other state the DPA is in (including bypass). This is a latching condition which is not
recovered from by the board receiving the normal reset input. To recover from the duress
condition, a momentary bypass input must be received (terminal BP). The reason for providing
a different input to reset duress is that the normal reset input (terminal RS) may be connected
to door or lock status in the automatic reset function.
The duress function can be used to signal real duress. A
momentary "panic" push button can be mounted near the door
which allows anyone to signal if they require assistance. In this
situation, it makes sense to have a keyswitch at the door which
operates the bypass input. An authorized person will come to
render assistance and to clear the duress alarm signal. Since the
DPA will also be operating its standard door prop alarm functions,
it should be noted that it will cause no harm if the same keyswitch
momentarily operates the reset and bypass input together. Thus
one keyswitch will be able to clear all latching alarm conditions.
Remember that momentary use of the bypass input does not
interfere with any other functions. The DPA is bypassed only when the bypass input is
maintained and the board is in the normal or authorized condition at this time.
8. TIME CONTROLLED INSTANT ALARM
Applications often exist where the DPA operates as a two stage door prop alarm during the day only.
At
night the affected door is not to be used, so an instant latching alarm from the DPA is desired.
By using a time clock such as Securitron's model DT-7, this can be achieved in either of two
ways.
+
L S
B P
F E
I N
RS
DC
N.O.
DURESS
SWITCH
ONE N.O.
SWITCH
PROVIDES
ALARM AND
DURESS
RESET