C7650A
Solid State Temperature Sensor
PRODUCT DATA
FEATURES
•
Senses temperature of outdoor air.
•
Long lasting thermistor sensing element is accurate
and stable over time.
•
•
•
When temperature of outdoor air increases, the
outdoor air damper is closed to a preset minimum
position.
When temperature of outdoor air is low, the outdoor
air damper is opened to reduce the cooling load in the
building.
Provides 10 to 20 mA output signal to W7459 Solid
State Economizer Control; setpoint is located on solid
state economizer control.
•
•
Sensor is enclosed in a rugged, corrosion-resistant
glass-fiber reinforced plastic case.
Compact size and lightweight construction provide
easy mounting in HVAC rooftop unit.
GENERAL
C7650A Solid State Thermistor Sensor is used with the
W7459 Solid State Economizer Control Package. The W7459
Solid State Economizer Control Package is usually mounted
on an M7405/M7415 Actuator. It permits the use of outdoor
air as the first stage of cooling in heating, ventilating and air
conditioning (HVAC) systems. The application is for
differential or single temperature economizer control on
HVAC equipment up to approximately 20 tons.
Contents
General ...............................................................................
Features ..............................................................................
Specifications ......................................................................
Ordering Information ...........................................................
Installation ...........................................................................
Operation ............................................................................
1
1
2
2
2
3
63-2499-1
Copyright © 1996 Honeywell Inc.
•
All Rights Reserved
C7650A SOLID STATE TEMPERATURE SENSOR
W7459 ECONOMIZER PACKAGE MOUNTED ON ACTUATOR
TR
L1
(HOT)
TR
SO
SR
24 Vac
TR1
TR1
L2
B
C
A
D
+
TEMPERATURE
SETPOINT
+
+
S
5
C7650A OUTDOOR
AIR TEMPERATURE
SENSOR
620 OHM
RESISTOR
1
3
2
4
1
TR
MINIMUM
POSITION
MIXED AIR
SENSOR
TR1
T
P
T1
P1
TR
OPEN
MINIMUM
POSITION
TR1
W7459 ECONOMIZER PACKAGE
ACTUATOR
M7577
1
SEE W7459 SPECIFICATIONS FOR ADDITIONAL
WIRING INFORMATION.
Fig. 2. Wiring Connections for C7650A Temperature Sensor.
Operation
CAUTION
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.
1. Before beginning installation, disconnect power
supply to prevent electrical shock or equipment
damage.
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.
2. When selecting the location, make sure the
sensor is not exposed to rain, snow, or direct
sunlight.
Location
The relationship between the C7650A output current and the
temperature is shown in Fig. 3.
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.
19
LED ON
18
The C7650A is designed to operate in 500 ft/min minimum
airflow.
D
17
LED ON
16
15
14
LED OFF
C
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
LED ON
LED OFF
B
13
12
LED ON
LED OFF
A
manufacturer or refer to Fig. 2 for typical wiring hookups.
11
10
9
LED OFF
95
85 90
OPERATION
100
40
60
DEGREES FAHRENHEIT
NOTE: A,B,C,D ARE W7459A SWITCHING SETPOINTS.
65
45
50
55
70
75
80
M7578A
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.
Fig. 3. C7650A Temperature Sensor Output Current.
63-2499—1
3
Home and Building Control
Honeywell Inc.
Honeywell Plaza
P.O. Box 524
Minneapolis MN 55408-0524
Home and Building Control
Honeywell Limited-Honeywell Limitée
155 Gordon Baker Road
North York, Ontario
Honeywell Asia Pacific Inc.
Room 3213-3225
Sun Hung Kai Centre
No. 30 Harbour Road
Wanchai
M2H 2C9
Hong Kong
Honeywell Europe S.A.
3 Avenue du Bourget
Honeywell Latin American Division
Miami Lakes Headquarters
B-1140 Brussels Belgium
14505 Commerce Way Suite 500
Miami Lakes FL 33016
Helping You Control Your World®
63-2499—1 G.H. Rev. 12-96 Printed in U.S.A.
|