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$er2 - The RTU-MP control is used with EconoMi$er2 (option or accessory) for outdoor air management. The damper position is controlled directly by the RTU-MP 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 CO2 sensor

Outdoor air CO2 sensor

Field Connections - Field connections for accessory sensors and input devices are made the RTU-MP, at plugs J1, J2, J4, J5, J11 and J20. All field control wiring that connects to the RTU-MP must be routed through the raceway built into the corner post as shown in Fig. 23. The raceway provides the UL required clearance between high- and low-voltage wiring. Pass the control wires through the hole provided in the corner post, then feed the wires thorough the raceway to the RTU-MP. Connect to the wires to the removable Phoenix connectors and then reconnect the connectors to the board.

Space Temperature (SPT) Sensors

Afield-supplied Byrant space temperature sensor is required with the RTU-MP to monitor space temperature. There are 3 sensors available for this application:

S 33ZCT55SPT, space temperature sensor with override button

S 33ZCT56SPT, space temperature sensor with override button and setpoint adjustment

S 33ZCT59SPT, space temperature sensor with LCD (liquid crystal display) screen, override button, and setpoint adjustment

Use 20 gauge wire to connect the sensor to the controller. The wire is suitable for distances of up to 500 ft. Use a three-conductor shielded cable for the sensor and setpoint adjustment connections. If the setpoint adjustment (slidebar) is not required, then an unshielded, 18 or 20 gauge, two-conductor, twisted pair cable may be used.

Connect T-55 - See Fig. 40 for typical T-55 internal connections. Connect the T-55 SEN terminals to RTU-MP J20-1 and J20-2. See Fig. 41.

1

2

3

4

5

6

RED(+)

 

 

 

 

 

 

WHT(GND)

CCN COM

 

 

 

 

 

 

BLK(-)

 

 

 

 

 

 

 

 

 

 

SEN

 

 

 

 

 

SW1

 

 

 

 

 

 

 

 

 

 

 

BRN (GND)

SENSOR WIRING

 

 

 

 

 

BLU (SPT)

 

C08201

551J

j

Fig. 40 - T-55 Space Temperature Sensor Wiring

 

SEN J20-1

SEN J20-2

C08460

Fig. 41 - RTU-MP T-55 Sensor Connections

Connect T-56 - See Fig. 42 for T-56 internal connections. Install a jumper between SEN and SET terminals as illustrated. Connect T-56 terminals to RTU-MP J20-1, J20-2 and J20-3 per Fig. 43.

1

2

3

4

5

6

RED(+)

 

 

 

 

 

 

WHT(GND)

CCN COM

 

 

 

 

 

 

BLK(-)

 

 

 

 

 

 

 

 

 

 

SEN

 

SET

 

 

 

SW1

 

 

 

 

BLK

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(T56)

 

 

 

 

 

 

BRN (GND)

SENSOR WIRING

 

 

 

 

 

BLU (SPT)

 

 

 

 

 

 

 

 

JUMPER

 

 

 

 

 

 

 

TERMINALS

 

 

 

 

 

 

 

AS SHOWN

Cool Warm

C08202

Fig. 42 - T-56 Internal Connections

23

Page 23
Image 23
Bryant 551J installation instructions Space Temperature SPT Sensors, Space Temperature Sensor Wiring