Mitsubishi Electric 800 Series Instruction Manual (Function page 438

*3 Initial value for the FR-E820-0470(11K) or higher and FR-E840-0230(11K) or higher.
 Block diagram of dancer control
Main speed command
*1
Dancer roll
setting point
Pr.133
PID set point
Convert to 0 to 100%
*1 The main speed can be selected in all operation modes, External (analog voltage input, multi-speed), PU (digital frequency setting) and
Communication.
 Outline of dancer control
• Dancer control is performed by setting "40 to 43" in Pr.128 PID action selection. The main speed command is the speed
command for each operation mode (External, PU, and communication). PID control is performed by the dancer roll position
detection signal, and the control result is added to the main speed command. For the main speed acceleration/deceleration
time, set the acceleration time to Pr.44 Second acceleration/deceleration time and the deceleration time to Pr.45
Second deceleration time.
Output frequency
NOTE
• Normally, set Pr.7 Acceleration time and Pr.8 Deceleration time to 0 s. When the Pr.7 and Pr.8 settings are large, dancer
control response becomes slow during acceleration/deceleration.
• If an automatic restart after instantaneous power failure is activated during dancer control, E.OC[] or E.OV[] is likely to occur.
In such case, disable the automatic restart after instantaneous power failure function (Pr.57 = "9999").
Acceleration/deceleration
of main speed
PID deviation
PID control
+
1
Kp(1+ +Td S)
Ti S
-
PID feedback
Terminal 4
PID adding value
Main speed
STF
Ratio
Pr.128 = 42, 43
X14
Pr.128 = 40, 41
Potentiometer
Dancer roll position detection
Output frequency
ON
Target frequency
Acceleration/
Limit deceleration
+
+
M
Time
16. (A) Application Parameters
16.6 Dancer control
11
12
13
14
15
16
17
18
19
20
437