Bryant 580J*04A, Руководство по установке

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Outdoor Air Quality Sensor (P/N 33ZCSENCO2 plus
weatherproof enclosure) — The sensor is designed to monitor
carbon dioxide (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. 53.
The outdoor air CO
2
sensor must be located in the economizer
outside air hood.
Fig. 53 — Outdoor Air Quality Sensor Cover
Wiring the Outdoor Air CO
2
Sensor — A dedicated power
supply 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 sen-
sor. See Fig. 53. Connect the 4 to 20 mA terminal to RTU Open
J4-5. Connect the SIG COM terminal to RTU Open J4-6. See
Fig. 54.
Fig. 54 — RTU Open / Outdoor CO
2
Sensor
(33ZCSENCO2) Connections
Space Relative Humidity Sensor or Humidistat
NOTE: The accessory space relative humidity sensor and
humidistat are not available for single phase (-J voltage
code) models.
Perfect Humidity™ 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 dehumidifica-
tion function of the unit. These pink wires are meant to be tied
to a space humidistat or thermidistat on an electromechanical
unit. On RTU Open equipped units these pink wires must be
connected to J11-7 and 8 to allow the Open board to operate
the dehumidification function for the unit. Disconnect the J11
Phoenix 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.
NOTE: Perfect Humidity is a factory-installed option
which is available for 07 models only.
Relative Humidity Sensors (Space or Duct Mounted) — The
accessory space humidity sensor (33ZCSENSRH-01) or duct
humidity 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. 55 and 56 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
normally open humidistat.
Fig. 55 — Space Relative Humidity Sensor Typical
Wiring
Humidistat — The accessory humidistat provides the RTU
Open insight to the relative humidity in the space. The humidi-
stat reads the RH level in the space and compares it to its set-
point to operate a dry contact. The humidistat is a dedicated in-
put on the configurable input 9 and tells the RTU Open when
the RH level is HIGH or LOW. The normal condition for hu-
midity is LOW. A normally open humidistat is the factory de-
fault control for the Perfect Humidity option.
Fig. 56 — Duct Relative Humidity Sensor Typical
Wiring
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)