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L1
(HOT)
L2
+
S
C7650A OUTDOOR
AIR TEMPERATURE
SENSOR
SEE W7459 SPECIFICATIONS FOR ADDITIONAL
1
WIRING INFORMATION.
CAUTION
1. Before beginning installation, disconnect power
supply to prevent electrical shock or equipment
damage.
2. When selecting the location, make sure the
sensor is not exposed to rain, snow, or direct
sunlight.
Location
The C7650A Temperature Sensor can be mounted in any
position; however, the sensor must be installed where it is
exposed to freely circulating air, but protected from rain and
direct sunlight.
The C7650A is designed to operate in 500 ft/min minimum
airflow.
Wiring
Disconnect power supply before beginning installation to
prevent electrical shock or equipment damage. All wiring
must comply with applicable codes and ordinances. Follow
the wiring information furnished by the equipment
manufacturer or refer to Fig. 2 for typical wiring hookups.
OPERATION
Control Dial Setting
Control setpoint scale is located on the W7459 Solid State
Economizer Control. Control points A, B, C, D are field
selectable; use A, B, C, D control points for temperature
sensing.
TR
SO
SR
620 OHM
1
RESISTOR
1
3
T
P
Fig. 2. Wiring Connections for C7650A Temperature Sensor.
C7650A SOLID STATE TEMPERATURE SENSOR
W7459 ECONOMIZER PACKAGE MOUNTED ON ACTUATOR
TR1
B
C
A
D
+
TEMPERATURE
SETPOINT
+
5
2
4
MINIMUM
POSITION
T1
OPEN
P1
W7459 ECONOMIZER PACKAGE
Operation
The C7650A Solid State Temperature Sensor is used with a
solid state economizer control and damper actuator to
proportion an outdoor air damper in a ventilation system.
When outdoor air temperature is higher than return air
temperature, the outdoor air damper closes to the minimum
position. When the outdoor air temperature and the return air
temperature are equal, the outdoor air damper proportions
open on a call for cooling.
The relationship between the C7650A output current and the
temperature is shown in Fig. 3.
19
LED ON
18
D
17
16
LED OFF
15
14
13
12
11
10
9
40
45
50
NOTE: A,B,C,D ARE W7459A SWITCHING SETPOINTS.
Fig. 3. C7650A Temperature Sensor Output Current.
3
TR
24 Vac
TR1
TR
MIXED AIR
TR1
SENSOR
TR
MINIMUM
TR1
POSITION
ACTUATOR
M7577
LED ON
C
LED ON
LED OFF
B
LED ON
LED OFF
LED OFF
60
65
55
70
75
80
85
DEGREES FAHRENHEIT
A
95
100
90
M7578A
63-2499—1
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