Instruction manual

2928
Tu n i n g
P ro c e d u re s
The Series 18/19/25 is an “on demand” autotuning controller
that automatically sets PID parameter values (Proportional
Band, Reset and Rate) before the process reaches setpoint. A
damping setting (menu level “02”) MUST be selected for auto-
tuning to take place. (see Notes on Damping, page 27). The
controller may also be tuned manually (see page 32).
Autotuning the Temperature Controller
1) With the power off and the process at ambient, apply
power and immediately put the controller in Standby mode
by holding the key for four seconds until [ StbY ]
flashes in the lower display window. If controller is in
menu level “00” or “01”, hold the Parameter/ Access
key for 11 seconds until [ Ac.Cd ] appears. Then
change to menu level “05”.
2) Press the key once and use the key to select
menu level “05”.
3) Enter the desired Setpoint Value using the appropriate
Raise or Lower key. [ StbY ] will continue to
flash.
4) Press the Parameter/Access key twice until [ SnSr ]
is displayed to make sure
that the proper sensor has been selected. Then set the
controller’s heating mode by pressing the
Parameter/Access key again until [ OUt1 ] is dis-
For best results in tun-
ing the temperature
controller, the setpoint
value should be at least
100°F above or below
ambient temperature.
While some processes
other than heat or cool
applications may
respond successfully to
autotuning procedures,
the controller must be
manually tuned for
most non-temperature
processes.
P a r a m e t e r
D e s c r i p t i o n s
Figure 12. Typical Lag Processes
Dead
Time