22
Table3 – RTU--MP Controller Inputs and Outputs
POINTNAME BACnetOBJECT
NAME TYPE OF I/O CONNECTIONPIN
NUMBERS
INPUTS
Space TemperatureSensor sptsens AI (10K Thermistor) J2 0 ---1 , 2
SupplyAir Temperature sat AI (10K Thermistor) J2---1,2
LocalOutside Air Temperature Sensor oatsens AI(10K Thermistor) J2---3,4
Space TemperatureOffset Pot sptopot AI (100K Potentiometer) J2 0 --- 3
Indoor Air Quality iaq AI (4 ---2 0 ma ) J4---2,3
Outdoor Air Quality oaq AI (4 ---2 0 ma ) J4---5,6
SafetyChain Feedback safety DI (24 VAC) J1---9
Compressor Safety compstat DI (24 VAC) J1---2
FireShutdown firedown DI (24 VAC) J1 --- 10
EnthalpySwitch enthalpy DI (24 VAC) J2---6,7
HumidistatInput Status humstat DI(24 VAC) J5 ---7,8
CONFIGURABLE INPUTS*
SpaceR elative Humidity sprh AI ( 4 ---2 0 ma ) J 4 --- 2,3 o r J4 ---5 , 6
Outside Air Relative Humidity oarh AI (4 --- 2 0 m a )
SupplyFan Status fanstat DI(24 VAC) J 5---1,2or J5 ---3,4or
J5 5,6 orJ 5---7,8
FilterStatus filtstat DI(24 VAC)
RemoteOccupancy Input remocc DI (24 VAC)
OUTPUTS
Economizer Commanded Position econocmd 4---20ma J2---5
SupplyFanRelayState sf DORelay (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
HeatStage 1 R elay State heat_1 DO Relay (24VAC , 1A) J1---6
HeatStage 2 R elay State heat_2 DO Relay (24VAC , 1A) J1---5
PowerEx haust Relay State aux_2 DO Relay (24VAC , 1A) J 1 1 ---3
Dehumidification Relay State humizer DO Relay (24VAC, 1A) J11 --- 7, 8
LEGEND
AI --- An a lo g In p u t
AO --- An a lo g O u tp ut
DI --- Dis c r e t e In p u t
DO --- Discrete Output
* Theseinputs (if installed) take the place of the def ault input on the specific channel according to sch ematic.
Par a ll el pi ns J 5--- 1 = J 2 --- 6 , J 5 --- 3 = J1 --- 1 0, J5 --- 5 = J 1 --- 2 a r e u se d fo r f ie ld --- i n st al la t io n.
The RTU--MP controller requires the use of a Byrant
space sensor. A standard thermostat cannot be used with
the RTU--MPsystem.
Supply Air Temperature (SAT)Sensor -- On FIOP--equipped
551J unit, the unit is supplied with a supply--air temperature
(SAT)sensor (33ZCSENSAT). This sensor is a tubular probe
type, approx 6--inches (12.7 mm) in length. It is a nominal
10--kohm thermistor.
The SATis factory--wired.T heSAT probe is wire--tiedto
the supply--airopening (on the horizontal opening end) in
its shipping position. Remove the sensor for installati on.
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--drillingscrews to secure the
sensor probe in a horizontal orientation. See Fig. 39.
SUPPLY AIR RETURN AIR
SUPPLY AIR
TEMPERATURE
SENSOR
ROOF
CURB
C08200
Fig. 39 --Typical Mount ing Location for Supply Air
Temperature(SAT) Sensor on Small Rooftop Units
551J
j