Outdoor Air Enthalpy Control; Differential Enthalpy Control - Carrier 50TC Series Installation Instruction

The LEDs on the RTU Open controller show the status of certain functions
If this LED is on...
Power
Rx
Tx
BO#
The Run and Error LEDs indicate control module and network status
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
NOTE: Refer to the RTU Open Multi- - Protocol Controller
Controls, Start- - Up, Operation and Troubleshooting manual
for complete configuration of RTU Open controller,
operating sequences and troubleshooting information. Refer
to the RTU Open v3 Integration Guide for details on
configuration and troubleshooting of connected networks.
Have a copy of these manuals available at unit start- - up.

Outdoor Air Enthalpy Control

(PNO 33CSENTHSW)
The enthalpy control (33CSENTHSW) is available as a
field- - installed accessory to be used with the EconoMi$er
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. 72.)
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. 72. Connect the
enthalpy control power input terminals to economizer
actuator power leads RED (connect to 24V) and BLK
(connect to GND).
Table 9 – LEDs
Status is...
The RTU Open controller has power
The RTU Open controller is receiving data from the network segment
The RTU Open controller is transmitting data over the network segment
The binary output is active
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
R
2
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 MSTP 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:
S Turn the RTU Open controller off, then on.
S Format the RTU Open controller.
S Download memory to the RTU Open controller.
S Replace the RTU Open controller.
Enthalpy
Switch
24V RED
GND BLK
LOW GRA
Factory Wiring Harness
Fig. 72 - - 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.
42
PL6-1 (24-V)
PL6-4 (COM)
7 CTB ECON
(P'LINK: to J4-2) or
(RTU Open: to J2-6)
C11160