Bryant 580J*16D Series, Installation Instructions Manual

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Outdoor Air Quality Sensor (P/N 33ZCSENCO2 plus weather-
proof enclosure) — The sensor is designed to monitor carbon di-
oxide (CO
2
) levels in the outside ventilation air and interface with
the ventilation damper in an HVAC system. The OAQ sensor is
packaged with an outdoor cover. See Fig. 80. The outdoor air CO
2
sensor must be located in the economizer outside air hood.
Fig. 80 — Outdoor Air Quality Sensor Cover
Wiring the Outdoor Air CO
2
Sensor — A dedicated power sup-
ply is required for this sensor. A two-wire cable is required to wire
the dedicated power supply for the sensor. The two wires should
be connected to the power supply and terminals 1 and 2.
To connect the sensor to the control, identify the positive (4 to
20 mA) and ground (SIG COM) terminals on the OAQ sensor.
See Fig. 78. Connect the 4 to 20 mA terminal to the RTU Open
controller at J4-5. Connect the SIG COM terminal to RTU Open
J4-6. See Fig. 81.
Fig. 81 — RTU Open / Outdoor CO
2
Sensor
(33ZCSENCO2) Connections
Space Relative Humidity Sensor or Humidistat
Perfect Humidity™ System Control Wiring — In units
equipped with the Perfect Humidity option there are two pink
(PNK) wires loose in the control box used to control the dehumid-
ification function of the unit. These pink wires are meant to be tied
to a space humidistat or thermidistat on an electro-mechanical
unit. On RTU Open controller systems equipped units these pink
wires must be connected to J11-7 and 8 to allow the RTU Open
board to operate the dehumidification function for the unit. Dis-
connect the J11 PCB style connector from the board and use the
plug screws to secure the pink wires in pins 7 and 8, reconnect the
plug to the board at J11.
Relative Humidity Sensors (Space or Duct Mounted) — The
accessory space humidity sensor (33ZCSENSRH-01) or duct hu-
midity sensor (33ZCSENDRH-01) is used to measure the relative
humidity of air within the space or return air duct. The RH reading
is used to control the Perfect Humidity option of the rooftop unit.
For wiring distances up to 500 ft (152 m), use a 3-conductor, 18 or
20 AWG shielded cable. The shield must be removed from the
sensor end of the cable and grounded at the unit end. The current
loop power for sensor is provided by the RTU Open controller as
24vdc. Refer to the instructions supplied with the RH sensor for
the electrical requirements and terminal locations. RTU Open
configurations must be changed after adding an RH sensor. See
Fig. 82 and 83 for typical RH sensor wiring.
• J4-1 or J4-4 = 24vdc loop power
• J4-2 or J4-5 = 4-20mA signal input
NOTE: The factory default for dehumidification control is nor-
mally open humidistat.
Fig. 82 — Space Relative Humidity Sensor Typical Wiring
Humidistat — The accessory humidistat provides the RTU Open
controller insight to the relative humidity in the space. The humid-
istat reads the RH level in the space and compares it to its setpoint
to operate a dry contact. The humidistat is a dedicated input on the
configurable input 9 and tells the RTU Open controller when the
RH level is HIGH or LOW. The normal condition for humidity is
LOW. A normally open humidistat is the factory default control
for the Perfect Humidity option. See Fig. 83.
Fig. 83 — Duct Relative Humidity Sensor Typical Wiring
To wire in the field:
• J5-8 = 24 VAC source for dry contact
• J5-7 = Signal input
COVER REMOVED S IDE VIEW
S EN
COM
J4-5
J4-6
OAQ S en s or
24 VAC
SW2
1 2 3 4 5 6
ON
Io Vin Gnd
Vo
MOUNTING
HOLES
WIRING
OPENING
Vin - J4-1 or J4-4 24Vdc
Io - J4-2 or J4-5 -20mA output
SPAN
ZERO
4-20
mA
VAC
or
VDC
GND 0-5V
or
0-10V
1 2 3 4 5 6
ON
J4-1 or J4-4 + 24 VDC
SUPPLY VOLTAGE
J4-2 or J4-5 (-)4 to 20 mA Current
LOOP OUTPUT TO RTU OPEN
RELATIVE HUMIDITY SENSOR
(POLARIZED MALE CONNECTOR)