Watlow Series 935B - Manual (Page 14)

14 Watlow Series 935B User’s Manual
Choosing a PID Setting Strategy
You may rely solely on the Auto-tune [`Aut] function (p. 34) and factory defaults to determine PID values for your
system, or you may use auto-tuning and additional manual adjustments. You must select dead band [``db] and
calibration offset [`CAL] values manually.
The Series 935B PID Menu is the first sub-menu you encounter after moving to the Operations Menu. The PID Menu
provides a software location to select the individual heat or cool proportional band, hysteresis, and cycle time values;
and the dead band, integral, derivative, and calibration offset values.
To go to the PID Menu:
1. Go first to the Operations Menu by pressing . and , simultaneously for three seconds.
2. Scroll through the Operations Menu with , until you see the [`Pid] prompt.
3. While pressing ß to display [``no] , choose [`YES] with . or , .
4. Release ß to see the first PID prompt.
NOTE: Access to the PID Menu and the prompts there varies with lockout function and output set-up. The PID
Menu is locked out when the 935B leaves the factory.
• Lockout function; the Lockout Tag [`tAg] function masks menus from view (if you cannot see a prompt, you can
make no change).
See Using Lockout Functions, p. 20.
• Output set-up; you must choose [hEAt] or [COOL] in either Output 1 or Output 2 to have access to the PID Menu.
With a [hEAt] only choice, [COOL] prompts are not visible, and vice versa.
See the Valid Output Functions Table, p. 5, or Setting Up Inputs and Outputs, p. 22.
NOTE: Proportional Band, Integral, Derivative, Dead Band, and Calibration Offset values are adjustable in
whole or tenth °F or °C, depending on input type
[``In] and [`C_F] Celsius/Fahrenheit Configuration Menu
choices.
Learn the PID Menu