Use the following procedure to mount, wire, and prepare
the receiver for operation:
1. Mount the mounting base. See
2. Set the DIP switches. See
.
3. Align the tabs on the edge of the mounting base
with the slots on the edge of the receiver housing,
and rotate the assembly onto its mounting base as
illustrated in Figure 3.
4. Use a 1/16 in. (1.5 mm) Allen wrench or Johnson
Controls T-4000-119 Allen-Head Adjustment Tool to
tighten the tamper-resistant set screw and fasten the
receiver enclosure to the mounting base.
Note:
To avoid damage to the unit, do not
overtighten the set screw.
5. Connect the SA bus cable from the controller to the
WRZ-7860-0 Receiver. See
.
Parts included
• One WRZ-7860-0 Receiver with factory-installed double-
sided adhesive foam tape on the back of the unit
• One installation guide sheet
Dimensions
See the following figure for dimensions and physical
features of the WRZ-7860-0 Receiver.
Figure 1: WRZ-7860-0 Receiver physical features and
dimensions, in. (mm)
Mounting
Location considerations
To locate a WRZ-7860-0 Receiver, follow these guidelines:
• Locate the receiver so that it is easily accessible in
the proximity of the field controller, on a Variable Air
Volume (VAV) duct, or just above or just below the
ceiling tiles.
Note:
Communication cables of various lengths
are available to connect the receiver SA bus. See
Table 4 for more details.
• Locate the receiver up to 100 ft (30 m) from the WRZ
Series Wireless Room Sensor in a building environment.
• Locate the receiver near the center of the associated
room sensor layout in multi-sensor applications.
• Locate the receiver on the same floor or building level
as the associated room sensor.
• Locate the receiver in the direct line-of-sight with the
room sensor whenever possible. Signal transmission is
best if the path between the room sensor and receiver
is as direct as possible. Line-of-sight is preferred but
not required, as long as the path is not blocked by large
metal objects.
• Mount the receiver so that the antenna symbol on the
cover near the LEDs is in a vertical orientation, up or
down. The antenna symbol indicates the approximate
location of the receiver’s internal onboard antenna.
Figure 2: Correct mounting orientation
• If you mount the receiver on duct work, such as a
VAV box, ideally the antenna portion of the receiver,
approximately 1/3 of the enclosure, hangs below the
duct work. Avoid pipes, duct work, or other metal
obstructions in the direct line-of-sight to the room
sensor.
• Avoid large metal obstructions, including equipment
rooms and elevator shafts, and concrete or brick walls
between the receiver and the room sensor.
• Do not mount the receiver in recessed areas or shelving
units.
Wireless signal transmission considerations
Line-of-sight transmission ranges between a WRZ Series
Wireless Room Sensor and a WRZ-7860-0 Receiver can
be less than the maximum distances shown in Table 1.
The effective transmission range for indoor applications
varies because of RF signal absorption and reflection due
to metal obstructions, walls or floors, and furniture found
in building interiors.
Table 1: Indoor line-of-sight transmission ranges
Range type
Transmission distance
Practical
average
100 ft (30 m)
Maximum
150 ft (45 m)
Use the manual occupancy override button on the WRZ
Series Wireless Room Sensor to test the RF signal strength
between an installed room sensor and receiver. Refer
to the
WRZ-7860-0 Receiver for One-to-One Wireless Room
Sensing Systems Technical Bulletin (LIT-12011641)
for
more information about how to determine the signal
strength between a WRZ Series Wireless Room Sensor
and a WRZ-7860-0 Receiver. If the RF signal path provides
unsatisfactory results, use a Johnson Controls ZFR18xx
Series Wireless Field Bus Router as a repeater and locate it
between the room sensor and the receiver.
WRZ-7860-0 Receiver for One-to-One Wireless Room Sensing Systems Installation Guide
2