PN# 500-18000
Page 7
Rev. D, 10/11
The time set jumper can be installed in any of three positions to
alter the factory set trailing edge delay of four seconds. The drawing
to the right shows the three choices. Four seconds is right for most
applications. 1/2 second is used for pattern set-up (see Section 6)
and certain applications where an external timer should replace the
XMS timer. For example, when the XMS is integrated with an
access control system (see Section 3.4), the XMS’s REX relay will
trigger the access system’s lock control relay and the magnetic lock
will release for the same amount of time that is programmed for
entry. If the set jumper is installed for the 1/2 second setting and
assuming a person is initially sensed by the XMS, then does not
immediately exit but moves around in front of the door, they will
continue to retrip the XMS. Persistant retripping of the XMS however,
will cause the Lock Control and REX Relay to remain latched until no movement is sensed for a
time greater than the set 1/2 second. It is important to note that this device has a “trailing
edge” delay – i.e. the device Lock Control and REX Relay will remain latched until a time
greater than the set time has expired since the last detected movement. If you used the
four second setting on the XMS for integration with an access control system, you would risk the
following problem. On initial detection, the access system starts timing for 10 seconds (as an
example) But the person does not immediately exit but moves around in front of the door so
that the XMS signal does not change but stays closed because of the four second timing
function. This allows the access system’s 10 second timer to time out and if the door is then
used, a “forced door” alarm signal will result. So the 1/2 second setting is right for integration
with access control systems.
Another application where you should employ the 1/2 second setting is when the XMS is
employed to initiate delayed exit when you are using Securitron’s model XDT timer.
The eight second setting is rarely used unless there is strong concern for maximum time being
allocated for egress even when movement is not maintained. The problem with an eight second
trailing edge delay is that entry security begins to be compromised by the door remaining open
for this length of time following exit.
6. DETECTION PATTERN SET-UP
At this point in the installation, the unit should be physically mounted and wired.
You should have also considered changing the jumper settings. Your final step is to
adjust the detection pattern for the optimum combination of egress safety and entry
security. Before doing this, set the time set jumper to the 1/2 second position
(shown in the drawing to the right). As you are adjusting the pattern, you will make
many quick tests of the unit and this will be most efficient if you don’t have to wait for a four or
eight second trailing edge timer to expire.
The XMS provides two means of adjustment. First, the entire barrel
assembly rotates 90 degrees so that the unit can look “out” or “down”.
Second, aiming screws (see Figure 2) are provided to laterally control the
pattern. To access the aiming screws, the barrel assembly must be
rotated so that the unit looks “out” so while you are making these
adjustments, you will need the barrel locking screw (see Figure 2) to be
loose.
In most applications, the unit is set to look “down”. The exception would
be if the XMS was mounted on a wall perpendicular to the door rather
than parallel to it. As the detection pattern proceeds outward from the
XMS it spreads. We are talking here about spreading in the same
direction as the barrel rotation rather than lateral spreading which is
constrained by the aiming screws. The drawing on the right provides an
example of this spreading. Assuming the XMS is mounted seven feet
above the floor, the pattern will spread out roughly three feet by the time it reaches the floor.
Maximum detection distance is approximately 20 feet.
The aiming screws are used as follows. They control internal louvers that point the same way
as the slots in the screws. When adjusting these screws, do not turn them past the point where
A
B
A
B
A
B
FOUR SECONDS
FACTORY SET
1/2 SECOND
8 SECONDS
A
B
3 FT. (1 M)
7 FT. (2.1 M)
