Tempco TEC-9300, Инструкция по эксплуатации

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5–9 Dual Set Point/PID
The TEC-9300 will switch between the two PID sets based on the
process value, the set point, or either of the event inputs. As the
control ramps up to the higher process value, the process charac-
teristics change. When this happens, the original PID values are
no longer valid. To achieve optimal control over the entire range,
a second PID set is used.
Example 1: Single set point/dual PID
A heat treating furnace is used over the range of 400°C to 1200°C.
1. Set the following parameters in the setup menu:
FUNC = FULL
A1FN = PV1H
A1MD = NORM
EIFN = PID2
PVMD = PV1
SPMD = MINR
2. Adjust the following parameters in the user menu:
A1SP = 800°C
A1HY = 1.0°C
PL1 = 100(%)
RAMP: According to the process requirement
SP1: According to the process requirement
3. Tune the first PID set at SP1=50°C and tune the second PID set
at SP1=1100°C, or set the proper values for PB1, TI1, TD1,
PB2, TI2, and TD2 directly according to previous records to
eliminate the auto-tuning sequence.
The circuit diagram and its temperature profile are shown as fol-
lows:
Example 2: Dual set point/PID
A heat treating furnace is required to harden the mold at a high
temperature (1000°C) for 30 minutes, then the mold is cooled
down with a programmable ramp (20°C/minute) to a lower set
point (200°C). Use the dual set point/PID and ramp/dwell func-
tions for this application.
1. Set the following parameters in the setup menu:
FUNC = FULL
A1FN = TIMR
EIFN = SP.P2
PVMD = PV1
SPMD = MINR
2. Adjust the following parameters in the user menu:
TIME = 30.0 (minutes)
RAMP = 20.0 (°C/minute)
SP1 = 1000°C
SP2 = 200°C
PL1 = 100(%)
3. Set the proper values for PB1, TI1, TD1, PB2, TI2, and TD2
directly according to previous records. For a new system, tune
the first PID set at SP1 = 800°C and tune the second PID set at
SP2 = 400°C.
The circuit diagram is the same as shown in figure 5.14. The tem-
perature profile is shown below: