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Table 8 – RTU Open Controller Inputs and Outputs
POINT NAME
BACnet OBJECT
NAME
TYPE OF I/O
CONNECTION PIN
NUMBER(S)
DEDICATED INPUTS
Space Temp / Zone Temp
zone_temp
AI (10K Thermistor)
J20---1, 2
Supply Air Temperature
sa_temp
AI (10K Thermistor)
J2---1, 2
Outdoor Air Temperature
oa_temp
AI (10K Thermistor)
J2---3, 4
Space Temperature Offset Pot
stpt_adj_offset
AI (100K Potentiometer)
J20---3
Safety Chain Feedback
safety_status
DI (24 VAC)
J1---9
Compressor Safety Status
comp_status
DI (24 VAC)
J1---2
Fire Shutdown Status
firedown_status
DI (24 VAC)
J1---10
Enthalpy Status
enthalpy_status
DI (24 VAC)
J2---6
Humidistat Input Status
humstat_status
DI (24 VAC)
J5---7
CONFIGURABLE INPUTS
Indoor Air CO2
iaq
AI (4---20 ma)
J4---2 or J4---5
Outdoor Air CO2
oaq
AI (4---20 ma)
Space Relative Humidity
space_rh
AI (4---20 ma)
Supply Fan Status*
sfan_status
DI (24 VAC)
J5---1 or J5---3 or
J5 5 or J5---7
Filter Status*
filter_status
DI (24 VAC)
Door Contact Input*
door_contact_status
DI (24 VAC)
Occupancy Contact*
occ_contact_status
DI (24 VAC)
OUTPUTS
Economizer Output
econ_output
AO (4---20ma)
J2---5
Supply Fan Relay State
sfan
DO Relay (24VAC , 1A)
J1---4
Compressor 1 Relay State
comp_1
DO Relay (24VAC , 1A)
J1---8
Compressor 2 Relay State
comp_2
DO Relay (24VAC , 1A)
J1---7
Heat Stage 1 Relay State
heat_1
DO Relay (24VAC , 1A)
J1---6
Heat Stage 2 Relay State
heat_2
DO Relay (24VAC , 1A)
J1---5
Power Exhaust Relay State
pexh
DO Relay (24VAC , 1A)
J11---3
Dehumidification Relay State
dehum
DO Relay (24VAC, 1A)
J11---7, 8
LEGEND
AI
--- Analog Input
AO
--- Analog Output
DI
--- Discrete Input
DO
--- Discrete Output
* These inputs (if installed) take the place of the default input on the specific channel according to schematic.
Parallel pins J5---1 = J2---6, J5---3 = J1---10, J5---5 = J1---2 are used for field---installation.
The RTU Open controller requires the use of a Carrier
space sensor. A standard thermostat cannot be used with
the RTU Open system.
Supply Air Temperature (SAT) Sensor —
On FIOP--equipped 48HC unit, the unit is supplied with a
supply--air temperature (SAT) sensor (33ZCSENSAT).
This sensor is a tubular probe type, approx 6--inches (152
mm) in length. It is a nominal 10--k ohm thermistor.
The SAT is factory--wired. The SAT probe is wire--tied to
the supply--air opening (on the horizontal opening end) in
its shipping position. Remove the sensor for installation.
Re--position the sensor in the flange of the supply--air
opening or in the supply air duct (as required by local
codes). Drill or punch a
1
/
2
--in. hole in the flange or duct.
Use two field--supplied, self--drilling screws to secure the
sensor probe in a horizontal orientation. See Fig. 50.
Outdoor Air Temperature (OAT) Sensor —
The OAT is factory--mounted in the EconoMi$er2 (FIOP
or accessory). It is a nominal 10k ohm thermistor attached
to an eyelet mounting ring.
EconoMi$er2 —
The RTU Open control is used with EconoMi$er2 (option
or accessory) for outdoor air management. The damper
position is controlled directly by the RTU Open control;
EconoMi$er2 has no internal logic device.
Outdoor air management functions can be enhanced with
field--installation of these accessory control devices:
Enthalpy control (outdoor air or differential sensors)
Space CO
2
sensor
Outdoor air CO
2
sensor
48H
C
Summary of Contents for 48HC Series
Page 24: ...24 C12251 Fig 42 ComfortLink Control Wiring Diagram 48HC 3 5 Ton Units 48HC ...
Page 27: ...27 C12254 Fig 45 48HC ComfortLink with Humidi MiZer Power Wiring Diagram 575V 3 Ph 60 Hz 48HC ...
Page 29: ...29 C101145 Fig 48 PremierLink Wiring Schematic 48HC ...
Page 30: ...30 C101146 Fig 49 PremierLink Wiring Schematic with Humidi MiZerR 48HC ...
Page 39: ...39 C101147 Fig 69 RTU Open System Control Wiring Diagram 48HC ...
Page 40: ...40 C101148 Fig 70 RTU Open System Control Wiring Diagram with Humidi MiZerR 48HC ...