Specifications

Section 2: System Description
2-25
SE 2854/55 MEDIUM RANGE SENSOR*
The SE 2854 sensor and the SE 2855 sensor have a read range of 2 to 12 inches (5 to 30.5 cm).
These two sensors differ only in that the SE 2854 has the coax connector located on the rear for
surface mounting using the SE 2700 standoff, and the SE 2855 has the coax connector located
on the edge for recessed mounting.
MSM Requirements. The SE 2854/55 sensors can only be used with the SE 774-A model MSM
with the MSM switch set to 2854/55.
The read range of the SE 2854/55 sensors depends upon the length of the coax to the ACU; this
is the case with or without an MSM. The read range versus coax length is show in Table 2-6.
Table 2-6: Coaxial Cable Length/Maximum Read Range
Coax Cable Len
g
th Maximum Read Ran
g
e
U
p
to 200 feet
(
0-60 m
)
12 inches
(
30.5 cm
)
200-500 feet
(
60-150 m
)
11 inch es
(
28 cm
)
500-1000 feet
(
150-300 m
)
9 inches
(
23 cm
)
The SE 2854/55 medium range sensors achieve best reading performance when the command
key is held parallel to the reader surface at a distance of 2 to 12 inches (5 to 30 cm).
SE 2804 COMPACT SENSOR
The SE 2804 compact sensor is intended primarily for indoor use where a small-geometry,
esthetically pleasing reader is desired. The read range is 0 to 3 inches (7.6 cm) and can operate
at a maximum coax length of 1,000 feet (300 M) from the ACU. The coax connector is located
on the back of the unit.
A two-colored lock status LED is visible through a hole in the lower right-hand corner of the front
cover of the SE 2804. Three wires, accessible through a hole in the base plate, may be used to
provide optional control of this LED. The color code for these wires is shown in Table 2-7.
* The medium range sensors, SE 2854 and 2855 may be used with the SE 818SX only. They
are not supported by the SE 818SC.