and the inner duct wall. Fasten the mounting flange with
the four screws as follows:
1. Loosen the probe retention screw, and separate the
flange from the assembled unit.
2. Drill a hole 7/8 to 1 in. (22 to 25 mm) diameter in
the duct for the transmitter’s probe.
3. Using the mounting flange as a template centered
on the hole, drill four 1/8 in. (3.18 mm) holes for the
mounting screws positioned as in Figure 1.
4. Fasten the mounting flange onto the duct using the
four screws provided.
5. Insert the probe a minimum of 3.0 in. (76.2 mm),
and tighten the probe retention screw on the
mounting flange.
Wiring
Power Supply Requirements
The transmitter requires a 24 VAC/VDC, Class 2 power
supply maintaining voltages of 18 to 30 VDC or 20 to
30 VAC. Although the power input includes a halfwave
rectifier, we recommend using a DC supply to avoid
excessive current peaks (current consumption: peak, 170
mA; average, 85 mA).
24 VAC Power Supply Connections
When more than one transmitter is connected to one
24 VAC transformer, a common loop is formed at the
controller, and the risk of a short circuit increases.
All commons must be at the same potential.
Note:
To avoid a short circuit, isolate the 24 V power
supply by providing a separate transformer for each
transmitter as shown in Figure 2.
Figure 2: Connecting Separate AC Supplies
(Recommended)
If several transmitters share one transformer, the phase
(~) must always be the same at each transmitter to
maintain polarity and avoid a short circuit via a shared
common line at the controller, as shown in Figure 3.
Figure 3: Connecting One AC Supply to Several
Transmitters (Not Recommended)
Connecting the Conduit Adaptor
1. Align the nut with the opening inside the enclosure,
and hold it in place.
2. Insert the adaptor body into the transmitter conduit
opening.
3. Manually tighten the adaptor into the nut, turning
in a Clockwise (CW) direction (see Figure 4).
Figure 4: Inserting the Conduit Adaptor
Important:
Do not overtighten the conduit
adaptor. Overtighting the conduit adaptor may
damage or displace the PCB.
4. Insert the wires through the conduit adaptor body
opening.
5. Tighten the adaptor onto the adaptor body by
turning the adaptor in a CW direction.
Wiring the PCB
About this task:
To wire the PCB’s input and output connections:
1. Open the transmitter cover.
2. Insert the wire carefully through the conduit
adaptor and then strip 1/4 in. (6.35 mm) of the wire
insulation to prepare the wire for connection to the
terminal block.
3. Connect the 24V supply between the positive (
)
and negative (
) terminals as shown in Figure 5.
CD-Pxx-00-0 Series Duct Mount CO
2
Transmitter Installation Guide
2