AD-1252 Thermal Dispersion Probe Airflow Measuring System Installation Instructions
9
Installing the DMPR-RA002 Electronic
Controller
1.
Securely mount the electronic controller on a wall
near the probes, leaving at least 12 in. (304 mm)
above the electronic controller to allow removal of
the cover. Use four field-supplied fasteners to
mount the enclosure in an appropriate location.
Use fasteners suitable for the wall material.
2.
Remove the six Phillips head screws securing the
cover.
3.
Open the cover and remove the appropriate
conduit plugs on the top of the electronic controller
for connection of the field wires to the circuit board
terminal blocks (Figure 12).
4.
Connect the supply power and outputs. Do not
over-tighten screw connections, terminals can be
twisted off of circuit board with application of too
much torque.See
.
Wiring
Whenever possible, use a transformer for each AD-
1252 System. If you use one transformer for multiple
AD-1252 Systems, ensure that the transformer is rated
with sufficient capacity for the total load of the
connected probes, sensors, and other devices.
Errors in the load calculations can lead to problems.
Wiring multiple low-voltage devices from a common
transformer can result in lower-than-expected voltage
at the device and higher-than-expected current draw
when devices are connected a great distance from the
power source.
Transformers for the DMPR-RA002 Electronic
Controller are not required to be isolated from other
devices. Isolation is only required to prevent electrical
fluctuations due to intermittent high loads from causing
problems with electronic devices.
See Figure 12 for supply power and output
connections.
Cable Specifications
The AD-1252 System requires a shielded CAT5e,
plenum rated wire, Cross-Over or Ethernet patch cable
will not work. Probes are connected to the transmitter
box using simple pairing with the following
specifications:
•
Shielded CAT5e solid plenum cable
•
four-pair shielded, twisted pair cable (see Table 5
for information about pin numbers and
corresponding wire colors)
•
24 AWG solid bare copper conductor meets or
exceeds CAT5e specification
•
Teflon
®
insulated, plenum jacket
•
CMP rated for use in any area used for air return,
drop ceilings, air ducts, and in public buildings
•
Compliant with EIA/TIA standards by ETL
•
Canadian Standards Association listed
See Table 4 for cable length recommendations.
Table 5: Pin Numbers and Corresponding Wire Colors for Simple Pairing
Pin Number
Wire Color
1
White and Green
2
Green
3
White and Orange
4
Orange
5
White and Blue
6
Blue
7
White and Brown
8
Brown
