Securitron EXD - Manual (Page 4)

PN# 500-13350
Page 4 Rev. E, 11/11
Certain code versions require the use of a door switch to accomplish reset. You may select any
door switch (switch should be closed when the door is closed) with minimum electrical ratings of
30 VDC and 250 mA as an alternate part of this system.
2.5 POWER SUPPLY
The EXD systems must operate on 12 or 24 VDC power. Securitron supplies a range of power
supplies (BPS series) to meet this requirement as part of the system. Selection of the power
supply depends first on whether 12 or 24 volts is preferred for the installation. Next, the
capacity of the power supply is selected according to how many doors are installed. Although
individual supplies could be installed for each door, an EXD system according to code includes a
central break from the fire alarm system so, since wires need to be run from a central point to
each door anyway, it is most cost effective to use one power supply to operate all the doors. 12
Volt power supplies in the BPS series range from 1-15 Amps in output capacity. 24 Volt supplies
range from 1-10 Amps. Battery backup may be supplied as an option (see Section 6.2.4).
3. DETAILED DELAYED EXIT FUNCTIONS
Exact code requirements for delayed exit vary somewhat in different jurisdictions. These
detailed variations will be addressed in Section 4. In general, however, delayed exit includes the
following components and sequences of operation.
In the normal condition, the door is locked. The initiate device is used to start the exit
sequence. Once the initiate switch opens, a nuisance delay period begins. The nuisance delay
period may be set for 1, 2 or 3 seconds. The duration of the nuisance delay period will depend
on the local code and/or on the desires of the end user. The nuisance delay function can also be
disabled. During the nuisance delay period, the XDT logic timer provides a pulsing relay output
which is used to operate a local Sonalert. This notifies the person at the door that he has
activated the initiate device. If he intends to exit, he must maintain pressure on the exit device
until the end of the nuisance delay period. If he releases the bar before the nuisance delay
times out, the local alarm signal will stop and the door will revert to normal (locked) mode.
Once the nuisance delay times out (or immediately if no nuisance delay has been set) the
release delay period begins. The XDT's local alarm output will go from pulsing to steady. This
will alert the person at the door that he need no longer maintain pressure on the exit hardware.
Once the release delay begins, it is irrevocable. The door will release at the end of the period.
Code mandated duration of the release delay period is 15 seconds although certain jurisdictions
allow extension to 30 seconds by local building or fire safety officials. The release delay period
on the XDT can therefore be set for 15 or 30 seconds and this total release delay time
includes the nuisance delay.
Once the door has released, it will remain released until manually relocked by a reset device.
This is a normally closed switch which is momentarily activated (opened). Relocking actually
occurs on reclosure of the switch. The reset device is Securitron's model MK, a momentary
spring loaded keyswitch, or a door switch (where required). We recommend that the keyswitch
be mounted at the door as this insures that security staff will actually inspect the door. In some
jurisdictions the reset device may be a doorswitch. With a doorswitch, relocking occurs from the
act of exiting the door. Certain codes require the use of a doorswitch or special timing
sequences as will be discussed in Section 4.
As mentioned earlier, the local alarm relay output incorporated on the board is necessary to
meet the codes. This relay pulses during the nuisance delay period, energizes during the release
delay period and is deenergized at all other times. For more powerful monitoring, the board
includes a second alarm signal called the remote alarm relay. This relay is normally
energized; it deenergizes to show an alarm condition. It signals alarm from the beginning
of the release delay period until the door is relocked. The remote alarm relay is intended to
signal to a security office that a security violation is occurring at the door. It ignores the
nuisance delay period as this should be seen as a "false alarm" unless the delay becomes
irrevocable. It also continues to signal until the door is relocked, correcting the security
violation. The remote alarm relay should also be considered a general "trouble" signal. If the
board loses power, this relay will de-energize signaling trouble. It is also used to signal other
optional alarm conditions described in Section 7.