Mitsubishi Electric FR-A700 Technical Manual page 378

[Pr.] Name
PID differential
134
*1
time
*1 [ Pr. 129, Pr. 130, Pr. 133 and Pr. 134] can be set during operation. These can also be set independently of the operation mode.
(1) Dancer control block diagram
Main speed command
*1
PID deviation
Dancer roll
+
setting point
[ ]
Pr. 133
PID set point
Convert to 0 to 100%
Terminal 4
*1 The main speed can be selected from all operation mode such as external (analog voltage input, multi-speed), PU (digital
frequency setting), communication (RS-485, CC-Link).
Set point and measured value of PID control
Set point
When measured value is input as current
(4 to 20mA)
Measured
When measured value is input as voltage
value
(0 to ±5V or 0 to ±10V)
(2) Dancer control overview
Performs dancer control by setting 40 to 43 in Pr. 128 PID
action selection.The main speed command is the speed
command of each operation mode (External, PU,
Network). Performs PID control by the position detection
signal of the dancer roller, then the result is added to the
main speed command. For acceleration/deceleration of the
main speed, set the acceleration time in Pr. 44 Second
acceleration/deceleration time in Pr. 45 Second deceleration
time.
* Set 0s normally to Pr. 7 Acceleration time and Pr. 8 Deceleration time. When
the Pr. 7 and Pr. 8 setting is large, response of dancer control during
acceleration/deceleration is slow.
Initial Setting
Value Range
For deviation ramp input, time (Td) required for providing only the
manipulated variable for the proportional (P) action.
0.01 to 10s
9999 As the differential time increases, greater response is made to a
deviation change.
9999 No differential control.
Acceleration/deceleration
of main speed
PID control
1
Kp(1+ + Td S)
Ti S
-
PID feedback
Input
[Pr.133]
4mA
0V
0V .......... 0%, 10V ...... 100%
Description
Ratio
[Pr. 128 = 42, 43]
[Pr. 128 = 40, 41]
Potentiometer
Input Signal
0 to 100%
.....
0%, 20mA .. 100%
.........
0%, 5V ........ 100%
PID adding value
Main speed
STF
412
Limit
+
X14
+
Dancer roll position detection
[Pr.267 ]
Current/Voltage Input
Setting
—
0
1
Switch : V
2
ON
PARAMETER
Available
Inverters
E700 D700
Target frequency
Acceleration/
deceleration
IM
Switch
—
Switch : I
Output frequency
Time