Rtu Open Control System Field Connections - Bryant 580J*04A Installation Instructions Manual

Supply Air Temperature (SAT) Sensor (33ZCSENSAT) —
This sensor is supplied with the 580J unit. This sensor is a tu-
bular 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 ship-
ping 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 / -in. hole in the flange or duct. Use two field-supplied, self-
2
drilling screws to secure the sensor probe in a horizontal orien-
tation. See Fig. 45.
SUPPLY AIR
TEMPERATURE
SENSOR
SUPPLY AIR
Fig. 45 — Typical Mounting Location for Supply Air
Temperature (SAT) Sensor on Small Rooftop Units
Outdoor Air Temperature (OAT) Sensor — This sensor is
factory-mounted in the EconoMi$er
is a nominal 10-k ohm thermistor attached to an eyelet mount-
ing ring.
EconoMi$er 2 (option or accessory) — The EconoMi$er 2
system is used with the RTU Open control for outdoor air man-
agement. The damper position is controlled directly by the
RTU Open control; the EconoMi$er 2 system 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 sensor
2
• Outdoor air CO sensor
2
RTU OPEN CONTROL SYSTEM FIELD CONNEC-
TIONS — Field connections for accessory sensors and input
devices are made the RTU Open, at plugs J1, J2, J4, J5, J11 and
J20. All field control wiring that connects to the RTU Open
must be routed through the raceway built into the corner post as
shown in Fig. 32. The raceway provides the UL required clear-
ance 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 Open. Connect to
the wires to the removable Phoenix connectors and then recon-
nect the connectors to the board.
Space Temperature (SPT) Sensors — There are two types of
SPT sensors available from Bryant, resistive input non-com-
municating (T55, T56, and T59) and Rnet communicating
(SPS, SPPL, SPP, and SPPF) sensors. Each type has a variety
of options consisting of: timed override button, set-point ad-
justment, a LCD screen, and communication tie in. Space tem-
perature can be also be written to from a building network or
zoning system. However, it is still recommended that return
air duct sensor be installed to allow stand-alone operation for
back-up. Refer to the configuration section for details on con-
troller configurations associated with space sensors.
ROOF
CURB
RETURN AIR
2 (FIOP or accessory). It
®
• 33ZCT55SPT, space temperature sensor with override
button (T-55)
• 33ZCT56SPT, space temperature sensor with override
button and set-point adjustment (T-56)
• 33ZCT59SPT, space temperature sensor with LCD (liq-
uid crystal display) screen, override button, and setpoint
adjustment (T-59)
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 re-
quired, then an unshielded, 18 or 20 gauge, two-conductor,
twisted pair cable may be used.
Connect T- 55 — See Fig. 43 for typical T-55 internal connec-
tions. Connect the T-55 SEN terminals to RTU Open J20-1 and
J20-2. See Fig. 46 and 47.
1 2
3 4
SEN
SW1
Fig. 46 — T-55 Space Temperature Sensor Wiring
SEN
SEN
Fig. 47 — RTU Open T-55 Sensor Connections
Connect T- 56 — See Fig. 45 for T-56 internal connections.
Install a jumper between SEN and SET terminals as illustrated.
Connect T-56 terminals to RTU Open J20-1, J20-2 and J20-3
per Fig. 48 and 49.
40
6
5 RED(+)
WHT(GND)
CCN COM
BLK(-)
BRN (GND)
SENSOR WIRING
BLU (SPT)
J20-1
J20-2