Bryant LEGACY 580J*20M Series, Installation Instructions Manual

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The RTU Open controller requires the use of a Bryant space
sensor. A standard thermostat cannot be used with the RTU
Open system.
Supply Air Temperature (SAT) Sensor — On FIOP-equipped
580J 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 in its shipping position. Remove the sensor
for installation. Re-position the sensor in the flange of the sup-
ply-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. 43.
Fig. 43 — Mounting Location for Supply Air
Temperature (SAT) Sensor on 580J Units
Outdoor Air Temperature (OAT) Sensor — The OAT is facto-
ry-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
FIELD CONNECTIONS — 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 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 Open.
Connect to the wires to the removable Phoenix connectors and
then reconnect the connectors to the board.
Space Temperature (SPT) Sensors — There are two types of
SPT sensors available from Bryant, resistive input non-commu-
nicating (T-55, T-56, and T-59) and Rnet communicating (SPS,
SPPL, SPP, and SPPF) sensors. Each type has a variety of op-
tions consisting of: timed override button, set point adjustment,
a LCD screen, and communication tie in. Space temperature 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 controller configurations as-
sociated with space sensors.
• 33ZCT55SPT, space temperature sensor with override
button (T-55)
• 33ZCT56SPT, space temperature sensor with override
button and setpoint adjustment (T-56)
• 33ZCT59SPT, space temperature sensor with LCD (liquid
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 (152 m). 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. 44 for typical T-55 internal connec-
tions. Connect the T-55 SEN terminals to RTU Open J20-1 and
J20-2. See Fig. 45.
Fig. 44 — T-55 Space Temperature Sensor Wiring
Fig. 45 — RTU Open T-55 Sensor Connections
Connect T-56 — See Fig. 44 for T-56 internal connections. In-
stall 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. 47.
SUPPLY AIR RETURN AIR
SUPPLY AIR
TEMPERATURE
SENSOR
ROOF
CURB
2 3 4 5 6 1
S W1
S EN
BRN (GND)
BLU ( S PT)
RED(+)
WHT(GND)
BLK(-)
CCN COM
S EN S OR WIRING
S EN
S EN
J20-1
J20-2