Outdoor Air Enthalpy Control; Differential Enthalpy Control; Return Air Enthalpy Sensor - Carrier 48HC Installation Instructions Manual

If this LED is on...
Power
Rx
Tx
DO#
If Run LED shows...
2 flashes per second
2 flashes per second
2 flashes per second
2 flashes per second
2 flashes per second
5 flashes per second
5 flashes per second
7 flashes per second
14 flashes per second
On

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. 82.)
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. 82. Connect the enthalpy
control power input terminals to economizer actuator power
leads RED (connect to 24V) and BLK (connect to GND).
The outdoor enthalpy changeover setpoint is set at the
enthalpy controller.
Enthalpy
Switch
24V RED
GND BLK
LOW GRA
Factory Wiring Harness
Fig. 82 - - Enthalpy Switch (33CSENTHSW) Connections
Table 9 – LEDs
The LEDs on the RTU Open show the status of certain functions
Status is...
RTU Open has power
RTU Open is receiving data from the network segment
RTU Open is transmitting data over the network segment
The digital output is active
The Run and Error LEDs indicate control module and network status
And Error LED shows...
Off
2 flashes, alternating with Run LED
3 flashes, then off
4 flashes,
then pause
On
On
Off
7 flashes per second, alternating with
Run LED
14 flashes per second,
alternating with Run LED
On
PL6-1 (24-V)
PL6-4 (COM)
7 CTB ECON
(P'LINK: to J4-2) or
(RTU Open: to J2-6)
C11160
Status is...
Normal
Five minute auto---restart delay after system error
Control module has just been formatted
Two or more devices on this network have the
same ARC156 network address
Exec halted after frequent system errors or
control programs halted
Exec start---up aborted, Boot is running
Firmware transfer in progress, Boot is running
Ten second recovery period after brownout
Brownout
Failure. Try the following solutions:
Turn RTU Open off, then on.
S
Format RTU Open.
S
Download memory to RTU Open.
S
Replace RTU Open.
S
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.
Return Air Enthalpy Sensor —
Mount the return- - air enthalpy sensor (33SENTSEN) in
the return- - air section of the economizer. The return air
sensor is wired to
(33CSENTHSW). See Fig. 83.
24V
– 4-20
Main
GND
+ VDC
Out
LOW
Outside Air
Enthalpy Switch
+ 24-36
VDC In
– 4-20 Main
Out
Fig. 83 - - Outside and Return Air Enthalpy Sensor
Wiring
47
the enthalpy controller
RED PL6-1 (24-V)
BLK PL6-4 (COM)
CTB ECON
GRA 7
(P'LINK: to J4-2) or
(RTU Open: to J2-6)
Return Air
Enthalpy
Sensor
C11161