Barnstead 47900 Operation Manual page 36

8 S & 4 16 S P M /OTP
EGMENT X EGMENT ROGRAMMABLE ODELS W
Gain Scheduling
G.SP: Gain Scheduling
Gain scheduling is the automatic transfer of
control between two sets of PID values. The
2416 controller does this at a presettable
process value. Gain scheduling is used for
difficult control processes which show large
changes in their response time or sensitivity
at high or low temperatures, or when heating
or cooling.
The G.SP gain schedule setpoint is factory
set at 700° C. The G.SP must be adjusted to
200°C from the desired setpoint temperature
when tuning.
Setting the Transfer Point
If gain scheduling has been enabled, "G.SP
will appear at the top of the PID list. This sets
the value at which the transfer will occur.
When the process value is below this level,
PID1 will be active and when it is above, Pid2
will be active. Set a value between the control
regions that show the greatest change to
achieve the best point of transfer.
Tuning
The two sets of PID values can be manually
set or automatically tuned. To tune automati-
cally you must tune above and below the
transfer point G.SP. If the process value is
below the transfer point G.SP, the calculated
values will automatically be inserted into the
(SEt 1) set and if the process value is above
G.SP, the calculated values will automatically
be inserted into the (SEt 2).
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