Securitron EXD - Manual (Page 13)

PN# 500-13350
Page 13 Rev. E, 11/11
based on the amount of current that may be supplied into a short circuit. An individual might
receive a burn from an arc or, in an extreme case, a fire might be started.
The BPS series power supply that operates your EXD installation may or may not include a
backup battery pack depending on local regulation and on the end user’s requirements. The
addition of batteries increases the high energy hazard as the battery pack is able to supply very
high current into a short circuit (much higher than the maximum output of any BPS series
supply).
So long as your EXD installation is correctly wired according to Figure 4, however, the
Polyswitches will protect against this type of hazard. For your safety, insure that they are not
bypassed.
6.3 POWER FAILURE AND POWER DROP CONSIDERATIONS
A related power issue is a description of how the system behaves upon loss of power or
reduction of the input voltage. It is always intended that the XDT logic timer is
permanently powered except in the event that the fire alarm system removes all
power from the delayed exit locking system.
In the "normal" condition, the timer lock control relay (C3) and the remote alarm relay
(C2) are energized. The local alarm relay (C1) is deenergized. In this condition, the
Magnalock is powered (secure) and no alarms are being signaled. If the timer loses power from
a broken wire for instance, the lock control relay will deenergize releasing the Magnalock. This
is a safety feature. The remote alarm relay will also deenergize which will signal trouble at the
door. This is a security feature. The local alarm relay will remain deenergized and therefore not
signal at the door as the local alarm relay is intended to signal a delayed exit event and without
power, the board is not capable of producing such an event; the Magnalock is immediately
released upon loss of board power.
If the system has been approved for the use of battery backup, loss of building power will not
immediately alter anything at the door as the batteries will take over. If power is out for an
extended period of time, however, the batteries will begin to drain and lose voltage. As an
additional safety feature, the XDT timer includes a low voltage sensing circuit. The board
will keep working normally as the voltage declines until it reaches roughly 70% of nominal. At
that point, the XDT will automatically act as if all power was removed. The Magnalock releases
and the remote alarm relay deenergizes, signaling trouble at the door.
7. OPTIONAL FUNCTIONS
The following optional functions are not necessary to meet delayed exit safety codes but may be
implemented as desired to increase the utility of the EXD system application. All of the optional
functions are enabled by altering the wiring of the XDT logic timer board, so the following
Sections all focus on the XDT.
FIG. 6: LOCK STATUS REPORTING WIRING
DC
RS
IN
FE
BP
LS
+
GREEN
WHITE
RE
D
“B” TYPE
MAGNALOCK
TO UTILIZE LOCK STATUS MONITORING,
REMOVE THE JUMPER FROM “+” TO “LS”,
TIE THE MAGNALOCK WHITE WIRE TO
THE RED WIRE AND CONNECT THE GREEN
WIRE TO TERMINAL “LS”. ALTERNATELY,
A DOORSWITCH CAN INPUT +V TO “LS”
WHEN THE DOOR IS CLOSED.
7.1 LOCK STATUS REPORTING
The LS input is for optional lock (or door) status reporting. Note that when the XDT board is
delivered, the LS terminal is jumpered to the "+" terminal. In this mode, the board interprets
the lock as being secure so no reporting occurs, and the board can be used for normal delayed
exit.