Optimization Of The Process Regulator; Brake Functions; Mechanical Holding Brake - GE AF-650 GP Design And Installation Manual

Application Set-Up Examples
Function
Set min. speed limits
Set motor speed max. limit
Set max. output frequency
Set S201 or S202 to wanted analog input function (Voltage (V) or current (I)).
NOTICE
Switches are sensitive - Make a power cycling keeping default setting of V.
5) Scale analog inputs used for reference and feedback
Set terminal 53 low voltage
Set terminal 53 high voltage
Set terminal 54 low feedback value
Set terminal 54 high feedback value
Set feedback source
6) Basic PID settings
Process PID Normal/Inverse
Process PID Anti Wind-up
Process PID start speed
Save parameters to keypad
Table 6.21 Example of Process PID Control set-up

6.5.3 Optimization of the Process Regulator

After completing the basic settings, optimize the propor-
tional gain, the integration time, and the differentiation
time (parameter PI-33 Process PID Proportional Gain,
parameter PI-34 Process PID Integral Time,
parameter PI-35 Process PID Differentiation Time). In most
processes, this can be done by following the guidelines:
1. Start the motor.
2. Set parameter PI-33 Process PID Proportional Gain
to 0.3 and increase it until the feedback signal
again begins to vary continuously.
3. Reduce the value until the feedback signal has
stabilized.
4. Lower the proportional gain by 40–60%.
5. Set parameter PI-34 Process PID Integral Time to 20
s.
6. Reduce the value until the feedback signal again
begins to vary continuously.
7. Increase the integration time until the feedback
signal stabilizes, followed by an increase of 15–
50%.
8. Only use parameter PI-35 Process PID Differen-
tiation Time for very fast-acting systems only
(differentiation time). The typical value is 4 times
the set integration time. Only use the differen-
tiator when the setting of the proportional gain
and the integration time has been fully
optimized. Make sure that oscillations on the
feedback signal are sufficiently dampened by the
lowpass filter on the feedback signal.
MG35M402
AF-650 GP™ Design and Installation Guide
Parameter Setting
F-18 300 RPM
F-17 1500 RPM
F-03 60 Hz
AN-10 0 V
AN-11 10 V
-5 °C
AN-24
35 °C
AN-25
PI-20 [2] Analog input 54
PI-30 [0] Normal
PI-31 [1] On
PI-32 300 RPM
K-50 [1] All to keypad
NOTICE
If necessary, start/stop can be activated several times to
provoke a variation of the feedback signal.

6.6 Brake Functions

Brake function is applied for braking the load on the
motor shaft, either as dynamic braking or mechanical
braking.

6.6.1 Mechanical Holding Brake

A mechanical holding brake mounted directly on the
motor shaft normally performs static braking. In some
applications, the static holding torque is working as static
holding of the motor shaft (usually synchronous
permanent motors). A holding brake is either controlled by
a PLC or directly by a digital output from the frequency
converter (relay or solid state).
NOTICE
When the holding brake is included in a safety chain:
A frequency converter cannot provide a safe control of a
mechanical brake. A redundancy circuitry for the brake
control must be included in the total installation.
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