48
Outdoor Air Quality Sensor
(P/N 33ZCSENCO2 plus weatherproof enclosure) —
The outdoor air CO
2
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.
COVER REMOVED
SIDE VIEW
C07135
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 sensor. See Fig. 51. Connect the 4 to 20 mA
terminal to the RTU Open controller at J4--5. Connect the
SIG COM terminal to the RTU Open controller at J4--6.
See Fig. 54.
4-20mA
SIG COM
J4-5
J4-6
OAQ Sensor/RH Sensor
24 VAC
C10739
Fig. 54 -- RTU Open Controller / Outdoor CO
2
Sensor
(33ZCSENCO2) Connections
Smoke Detector/Fire Shutdown (FSD) —
On 548J units equipped with factory--installed Smoke
Detector(s), the smoke detector controller implements the
unit shutdown through its NC contact set connected to the
unit’s CTB input. The FSD function is initiated via the
smoke detector’s Alarm NO contact set. The RTU Open
controller communicates the smoke detector’s tripped status
to the BAS building control. See Fig. 44 (RTU Open
System Control Wiring Diagram).
The
Fire
Shutdown
Switch
configuration,
MENU
Config
Inputs
input 5
, identifies the normally
open status of this input when there is no fire alarm.
Space Humidity Sensor or Humidistat —
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. 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 controller configurations must be changed after
adding an RH sensor. See Fig. 55 and 56 for typical RH
sensor wiring.
S
J4--1 or J4--4 = 24vdc loop power
S
J4--2 or J4--5 = 4--20mA signal input
NOTE
: The factory default for dehumidification control
is normally open humidistat.
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
C11087
Fig. 55 -- Space Relative Humidity Sensor Typical
Wiring
Summary of Contents for 548J*17 D Series
Page 4: ...4 a548J 015 Fig 2 Unit Dimensional Drawing Size 17 Units ...
Page 5: ...5 a548J 016 Fig 2 Unit Dimensional Drawing Size 17 Units cont ...
Page 6: ...6 a548J 017 Fig 2 Unit Dimensional Drawing Size 17 Units cont ...
Page 7: ...7 a548J 018 Fig 3 Unit Dimensional Drawing Size 24 Units ...
Page 8: ...8 a548J 019 Fig 3 Unit Dimensional Drawing Size 24 Units cont ...
Page 9: ...9 a548J 020 Fig 3 Unit Dimensional Drawing Size 24 Units cont ...
Page 13: ...13 C10139 Fig 7 Roof Curb Details Size 17 Units ...
Page 14: ...14 C10140 Fig 8 Roof Curb Details Size 24 Units ...
Page 19: ...19 a50 9696 Fig 20 548J 17 24 Control Wiring Diagram with VFD Option ...
Page 20: ...20 a50 9697 Fig 21 Typical 548J 17 24 Power Wiring Diagram 208 230V 3 Phase 60Hz unit shown ...
Page 44: ...44 a50 9699 Fig 44 RTU Open System Control Wiring Diagram ...
