User`s manual

535 User's Manual Chapter 7 81
Applications
D. SLIDEWIRE POSITION PROPORTIONING CONTROL
Slidewire position proportioning utilizes a slidewire feedback signal to determine
the actual position of the actuator being controlled.
Hardware Configuration
• The controller must have the Slidewire Feedback option installed. Refer to
the order code in Chapter 1 for more information.
• The controller must have mechanical relays, solid state relays or DC logic
modules installed in the first two output sockets.
• The Slidewire does NOT have to be wired to the controller in order to set up
position proportioning.
Software Configuration
1. To configure the controller before wiring the slidewire feedback signal to
the controller, complete these steps:
a. Go to the CONTROL menu.
b. Set a value for PV BREAK.
c. Go to the SPECIAL menu.
d. Set a value for DES. OUTPT.
e. Set a value for PWR.UP:OUT.
f. Go to SER. COMM. menu.
g. Set a value for SHED OUT.
2. Place the controller under manual control.
3. Go to the CONFIG. menu.
4. Set CTRL. TYPE to POS. PROP (position proportioning).
5. Set P.P. TYPE to SLIDEWIRE.
6. Go to the CONTROL menu.
7. For S/W RANGE, specify the full range resistance of the slidewire from end-
to-end. With a 100 ohm slidewire, this parameter should be set to 100.
8. Scroll to OPEN F/B (Open feedback). Enter the ohm value when the actua-
tor is fully open (0 to 1050 ohms).
9. Scroll to CLOSE F/B (Closed feedback). Enter the ohm value when the ac-
tuator is fully closed (0 to 1050 ohms).
10.Measure the actual slidewire value at the terminals (10 and 11).
As an alternative, set up these two parameters dynamically. Before enter-
ing Set Up set the manual output at 100%. Enter Set Up and change the
OPEN F/B value until the actuator just reaches its full open position.
Exit Set Up and set the manual output to 0%. Enter configuration and change
the CLOSE F/B value until the actuator just reaches its full closed position.
11.Set the parameter P. PROP. D.B., which is used to eliminate cycling of the
motor. A low deadband setting may result in motor overspin or cycling. A
high deadband will result in reduction of sensitivity. To set:
a. Go to the TUNING menu.
b. Set P. PROP. D.B. to .5%.
c. Place controller under Manual control.
d. Change the output percentage and observe if the valve stabilizes at
the new value.
NOTE: OPEN F/B and CLOSE F/B
values are always reference to the
CCW end of the Slidewire.
NOTE: P.PROP.D.B. can only be
configured if the Slidewire Feedback is
wired to the controller.
CAUTION!
The relay in socket 1 drives the motor
counterclockwise and the relay in
output socket 2 drives the motor
clockwise.
This is important for:
• Wiring the outputs
• Selecting the control ACTION:1
parameter, or
• Determining the normally open or
normally closed relays,
The configuration choices influence
the way the position proportioning
algorithm works.