Honeywell AUTOMATIC CONTROL SI Edition, Engineering Manual

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ENGINEERING MANUAL OF AUTOMATIC CONTROL
ELECTRIC CONTROL FUNDAMENTALS
104
T1
W R B
T2
OPEN
LIMIT
SWITCH
CLOSE
LIMIT
SWITCH
ACTUATOR
LINE VOLTAGE
TRANSFORMER
C2513
MOTOR
DRIVE
SHAFT
CAM
W R B
CONTROLLER
CCW
WINDING
(CLOSE) CW
WINDING
(OPEN)
T1
W R B
T2
OPEN
LIMIT
SWITCH
CLOSE
LIMIT
SWITCH
ACTUATOR
LINE VOLTAGE
TRANSFORMER
C2515
MOTOR
DRIVE
SHAFT
CAM
W R
B
CONTROLLER
CCW
WINDING
(CLOSE) CW
WINDING
(OPEN)
Fig. 12. Series 60 Two-Position Control Circuit.
Low-voltage controllers cannot be used on line-voltage
control circuits. If the control circuit is low voltage, it can use
either a line-voltage controller or any low-voltage, spdt, or
floating controller.
OPERATION
Figure 12 illustrates the actuator in the closed position. On
a drop in temperature or pressure, the controller contacts close
R to B and open R to W (Fig. 13). The OPEN winding is
energized and the actuator shaft rotates cw until it reaches the
limit of travel and opens the OPEN limit switch (Fig. 14). The
actuator remains in this position until a rise in temperature or
pressure causes the controller contacts R to B to open and R to
W to close. The CLOSE coil is then energized and the actuator
shaft rotates ccw until it reaches the limit of travel and opens
the CLOSE limit switch.
NOTE: Most Honeywell Series 60 controllers close R to B on
a fall in the controlled variable and R to W on a rise.
Fig. 13. Series 60 Initial Control Action on
a Temperature (or Pressure) Drop.
Fig. 14. Series 60 Final Control Action
at End of Open Stroke.
T1
W R B
T2
OPEN
LIMIT
SWITCH
CLOSE
LIMIT
SWITCH
ACTUATOR
LINE VOLTAGE
TRANSFORMER
C2514
MOTOR
DRIVE
SHAFT
CAM
W R B
CONTROLLER
CCW
WINDING
(CLOSE)
CW
WINDING
(OPEN)