Sizes - Carrier 50TCQD Installation Instructions Manual

Economizer controls —
Outdoor Air Enthalpy Control (PNO 33CSENTHSW) - -
The enthalpy control (33CSENTHSW) is available as a
field- - installed accessory to be used with the EconoMi$er2
damper system. The outdoor air enthalpy sensor is part of
the enthalpy control. (The separate field- - installed
accessory return air enthalpy sensor (33CSENTSEN) is
required for differential enthalpy control. See Fig. 35.)
Locate the enthalpy control in the economizer next to the
Actuator Motor. Locate two GRA leads in the factory
harness and connect the gray lead labeled "ESL" to the
terminal labeled "LOW". See Fig. 35. Connect the
enthalpy control power input terminals to economizer
actuator power leads RED (connect to 24V) and BLK
(connect to GND).
Enthalpy
Switch
24V
GND
LOW
Fig. 35 - - Enthalpy Switch (33CSENTHSW) Connections
The outdoor enthalpy changeover setpoint is set at the
enthalpy controller.
Differential Enthalpy Control — Differential enthalpy
control is provided by sensing and comparing the outside
air and return air enthalpy conditions. Install the outdoor
air enthalpy control as described above. Add and install a
return air enthalpy sensor.
24V
– 4-20
Main
GND
+ VDC
Out
LOW
+ 24-36
VDC In
– 4-20 Main
Out
Fig. 36 - - Outside and Return Air Enthalpy Sensor
Wiring
RED
ECONO
MOTOR
BLK
CTB
GRA 7
ESL
ECON
Factory Wiring Harness
C09026
RED
ECONO
MOTOR
BLK
GRA
ESL
C09027
To wire the return air enthalpy sensor, perform the
following:
1. Use a 2- - conductor, 18 or 20 AWG, twisted pair cable
to connect the return air enthalpy sensor to the enthal-
py controller.
2. Connect the field- - supplied RED wire to (+) spade
connector on the return air enthalpy sensor and the
(+) terminal on the enthalpy controller. Connect the
BLK wire to (- - ) spade connector on the return air en-
thalpy sensor and the (- - ) terminal on the enthalpy
controller.
Indoor Air Quality (CO sensor) — The indoor air quality
2
sensor accessory monitors space carbon dioxide (CO
levels. This information is used to 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 temperature
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
2
2000 ppm and a linear mA output of 4 to 20. Refer to the
instructions supplied with the CO
requirements and terminal locations. See Fig. 37 for
typical CO sensor wiring schematic.
2
H G 24 VAC
OR
+ -
24 VDC
2 1 8 7 6 5 4 3 2 1
J3 J4
Fig. 37 - - Indoor/Outdoor Air Quality (CO
(33ZCSENCO2) - - Typical Wiring Diagram
To accurately monitor the quality of the air in the
conditioned air space, locate the sensor near a return- - air
grille (if present) so it senses the concentration of CO
leaving the space. The sensor should be mounted in a
location to avoid direct breath contact.
Do not mount the IAQ sensor in drafty areas such as near
supply ducts, open windows, fans, or over heat sources.
Allow at least 3 ft (0.9 m) between the sensor and any
corner. Avoid mounting the sensor where it is influenced
by the supply air; the sensor gives inaccurate readings if
24
)
2
sensor for electrical
2
+ 0-10VDC
- SIG COM
+
4-20mA
} ALARM
NC
COM RELAY
NO CONTACTS
C08635
) Sensor
2
2