Field Connections - Carrier WeatherMaster 50HC14 Installation Instructions Manual

ECONOMI$ER2
The RTU Open controller is used with EconoMi$er2 (fac-
tory-installed option or field-installed accessory) for outdoor
air management. The damper position is controlled directly
by the RTU Open controller; EconoMi$er2 has no internal
logic device.
Outdoor air management functions can be enhanced with
field-installation of these accessory control devices:
Enthalpy control (outdoor air or differential sensors)
Space CO sensor
2
Outdoor air CO sensor
2

Field Connections

Field connections for accessory sensors and input devices
are made through the RTU Open controller, at plugs J1, J2,
J4, J5, J11 and J20. All field control wiring that connects to
the RTU Open controller must be routed as shown in Fig. 39.
The routing provides the UL required clearance between high
and low-voltage wiring. Connect to the wires to the remov-
able Phoenix connectors and then reconnect the connectors to
the board.
SPACE TEMPERATURE (SPT) SENSORS
There are two types of SPT sensors available from Carrier:
resistive input non-communicating (T-55, T-56, and T-59)
and Rnet communicating (SPS, SPPL, SPP, and SPPF) sen-
sors. Each type has a variety of options consisting of: timed
override button, set point adjustment, a LCD screen, and
communication tie-in. Space temperature can be also be writ-
ten to from a building network or zoning system. However, it
is still recommended that return air duct sensor be installed to
allow stand-alone operation for back-up. Refer to the config-
uration section for details on controller configurations associ-
ated with space sensors.
Field connections to T-55, T-56 and T-59 are provided as
examples.
• 33ZCT55SPT, space temperature sensor with override
button (T-55)
• 33ZCT56SPT, space temperature sensor with override
button and setpoint adjustment (T-56)
• 33ZCT59SPT, space temperature sensor with LCD (liq-
uid crystal display) screen, override button, and setpoint
adjustment (T-59)
Use 20 gauge wire to connect the sensor to the controller.
The wire is suitable for distances of up to 500 ft. Use a three-
conductor shielded cable for the sensor and setpoint adjust-
ment connections. If the setpoint adjustment (slidebar) is not
required, then an unshielded, 18 or 20 gauge, two-conductor,
twisted pair cable may be used.
Connect T-55
See Fig. 63 for typical T-55 internal connections. Connect
the T-55 SEN terminals to the RTU Open controller at J20-1
and J20-2. See Fig. 82.
SEN
SEN
Fig. 82 — RTU Open Controller T-55 Sensor
Connections
Connect T-56
See Fig. 65 for T-56 internal connections. Install a jumper
between SEN and SET terminals as illustrated. Connect T-56
J20-1
J20-2
56
terminals to the RTU Open controller at J20
3 per Fig. 83.
SEN
SEN
Jumper
SET
SET
Fig. 83 — RTU Open Controller T-56 Sensor
Connections
Connect T-59
The T-59 space sensor requires a separate, isolated power
supply of 24 vac. See Fig. 84 for internal connections at the
T-59. Connect the SEN terminal (BLU) to the RTU Open
controller at J20 1. Connect the COM terminal (BRN) to J20
-
2. Connect the SET terminal (STO or BLK) to J20
BLK (STO)
BRN (COM)
BLU (SPT)
OR SET SEN
OPB COM- PWR+
NOTE: Must use a separate isolated transformer.
Fig. 84 — Space Temperature Sensor Typical Wiring
(33ZCT59SPT)
INDOOR AIR QUALITY (CO
The indoor air quality sensor accessory monitors space
carbon dioxide (CO ) levels. This information is used to
2
monitor IAQ levels. Several types of sensors are available,
for wall mounting in the space or in return duct, with and
without LCD display, and in combination with space tem-
perature sensors. Sensors use infrared technology to measure
the levels of CO present in the space air.
2
The CO sensors are all factory set for a range of 0 to 2000
2
ppm and a linear mA output of 4 to 20. Refer to the instruc-
tions supplied with the CO
2
and terminal locations. See Fig. 68 for typical CO
wiring schematic.
To accurately monitor the quality of the air in the condi-
tioned air space, locate the sensor near a return-air grille (if
present) so it senses the concentration of CO
space. The sensor should be mounted in a location to avoid
direct breath contact.
1, J20 2 and J20
- -
J20-1
J20-2
J20-3
3.
-
J20-3
SENSOR
J20-2
WIRING
J20-1
POWER
WIRING
24 VAC
) SENSOR
2
sensor for electrical requirements
sensor
2
leaving the
2
-
-