Controlling Valves (Can Be Used With A Position-Proportional Model) - Omron E5*C Series User Manual

5 Advanced Operations
5-21 Controlling Valves (Can Be Used with
a Position-proportional Model)
You can use position-proportional control to control a value with a control motor. With position-propor-
tional control, you can use either close control or floating control.
Precautions for Correct Use
The following functions cannot be used with position-proportional control.
• ON/OFF control
• P and PD control during floating control
• 40% AT during floating control
• ST
• LBA
• HB and HS alarms
 Control Method
Close control
Floating control
 Motor Calibration
The valve position is calibrated and the travel time from completely open to completely closed is set
automatically. You can then check the valve opening with the Valve Opening Monitor parameter. If
you set the Motor Calibration parameter to ON, the valve will open completely and close completely,
and then the setting of the parameter will change to OFF when the measurement has been
completed. "ERR" will be displayed if any of the following errors occurs during execution. If an error
occurs, check the wiring and other factors and execute motor calibration again.
• The potentiometer input value does not change or changes backward between completely
open and completely closed because the wiring is wrong.
• The value of the potentiometer input is incorrect because of a broken wire, noise, or other
factor.
Note: Do not change to any other parameter during calibration.
 Valve Opening Monitor
You can monitor the valve opening.
You can select either the measured opening or the estimated opening only with the
E5EC-PR@-8@@ or E5AC-PR@-8@@. (The Digital Controller must be manufactured in August 2014
or later (version 2.2 or higher).)
Measured opening
5 - 62
A potentiometer is connected and the valve opening and travel time are used to control
valve operation. Always perform motor calibration before actual operation.
Valve operation is controlled without a potentiometer by estimating the valve opening
from the travel time. Always set the travel time before actual operation.
The valve opening that was measured with a potentiometer is displayed. To monitor the
measured opening of the valve, select the measured opening for the Valve Opening
Monitor Selection parameter, connect a potentiometer, and then perform motor
calibration.
Application: Use this setting when you want to display the actual opening.
E5@C Digital Temperature Controllers User's Manual (H174)