Watlow CLS200 - Table 5.5 - Application Example: Setting up Differential Control

CLS200 Series User’s Guide
Chapter 5: Enhanced Features
114
To set up this application, you would do the following:
1. Change the display to loop 2, and then enter the setup parameters. Go to the first screen in
Table 5.5.
2. Follow the steps in Table 5.5 to configure the process variable retransmit option.
Table 5.5 — Application Example: Setting Up Differential Control
DISPLAY USER INPUT
ALARM
SETUP LOOP 02
RATIO CONTROL?
Press YES to set up the cascade parameters with loop 2.
ALARM
02 RATIO CONTROL
MSTR LOOP? 01
Assign loop 01 as the master loop. Press ENTER.
ALARM
02 RATIO CONTROL
MIN SP? 300.0
Enter the minimum ratio loop setpoint. For this example, we
will use 300.0˚ F. Press ENTER.
ALARM
02 RATIO CONTROL
MAX SP? 400.0
Enter the maximum ratio loop setpoint. For this example, we
will use 400.0˚ F. Press ENTER.
ALARM
02 RATIO CONTROL
CTRL RATIO? 1.0
Enter the control ratio, which is the multiple applied to the
master process variable. In this example the ratio is 1.0.
Press ENTER.
ALARM
02 RATIO CONTROL
SP DIFF.? 50
Enter the setpoint differential (or offset). For this example, we
have an offset of +50. Press ENTER.
3. Press BACK several times until the normal loop display appears. The setpoint of loop 2 will
now be equal to process variable of loop 1 plus 50°F.
4. To complete the differential control setup, loop 1 and loop 2 must be configured for inputs,
outputs, and alarms. See Chapter 4: Setup for information on loop setup.