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

Page: 44 / 56

44
.
Fig. 46 — T-56 Internal Connections
Fig. 47 — RTU Open T-56 Sensor Connections
Connect T-59 — The T-59 space sensor requires a sepa-
rate, isolated power supply of 24 VAC. See Fig. 48 for internal
connections at the T-59. Connect the SEN terminal (BLU) to
RTU Open J20-1. Connect the COM terminal (BRN) to J20-2.
Connect the SET terminal (STO or BLK) to J20-3.
Fig. 48 — Space Temperature Sensor Typical Wiring
(33ZCT59SPT)
Indoor Air Quality (CO
2
) Sensor — The indoor air quality sen-
sor accessory monitors space carbon dioxide (CO
2
) levels. This
information is used to monitor IAQ levels. Several types of sen-
sors are available, for wall mounting in the space or in return
duct, with and without LCD display, and in combination with
space temperature sensors. Sensors use infrared technology to
measure the levels of CO
2
present in the space air.
The CO
2
sensors are all factory set for a range of 0 to 2000
ppm and a linear mA output of 4 to 20. Refer to the instructions
supplied with the CO
2
sensor for electrical requirements and ter-
minal locations. See Fig. 49 for typical CO
2
sensor wiring sche-
matic.
To accurately monitor the quality of the air in the conditioned
air space, locate the sensor near a return-air grille (if present) so it
senses the concentration of CO
2
leaving the space. The sensor
should be mounted in a location to avoid direct breath contact.
Do not mount the IAQ sensor in drafty areas such as near sup-
ply ducts, open windows, fans, or over heat sources. Allow at
least 3 ft (0.9 m) between the sensor and any corner. Avoid
mounting the sensor where it is influenced by the supply air; the
sensor gives inaccurate readings if the supply air is blown direct-
ly onto the sensor or if the supply air does not have a chance to
mix with the room air before it is drawn into the return airstream.
2
3
4 5 6 1
S W1
S EN
S ET
Cool Warm
BRN (GND)
BLU ( S PT)
RED(+)
WHT(GND)
BLK(-)
CCN COM
S EN S OR WIRING
JUMPER
TERMINAL
S
A S S HOWN
BLK
(T56)
S EN J20-1
J20-2
S EN
S ET
J u mper
J20- 3
S ET
OR SET SEN
OPB COM- PWR+
BLU (SPT)
BLK (STO)
24 VAC
SENSOR
WIRING
POWER
WIRING
BRN (COM)
NOTE: Must use a separate isolated transformer.
J20-3
J20-2
J20-1