Mitsubishi Electric RD77MS2 User Manual page 200

■Precautions at control mode switching
• The start complete signal and the positioning complete signal do not turn ON at control mode switching.
• When "30: Control mode switch", "31: Speed control", or "32: Torque control" is set in "[Md.26] Axis operation status", the
BUSY signal turns ON.
• The motor speed might change momentarily at switching from the speed control mode to the torque control mode.
Therefore, it is recommended that the control mode is switched from the speed control to the torque control after the
servomotors stop.
• Use the continuous operation to torque control mode for the usage such as pressing a workpiece. Do not execute the
continuous operation to torque control in the speed control mode. Otherwise, an unexpected operation might occur at
switching to the position control mode.
• "In speed control flag" ([Md.31] Status: b0) does not turn ON during the speed control mode in the speed-torque control.
■Operation for "Position control mode  Speed control mode switching"
When the position control mode is switched to the speed control mode, the command speed immediately after the switching is
the speed set in "speed initial value selection (b8 to b11)" of "[Pr.90] Operation setting for speed-torque control mode".
Speed initial value selection ([Pr.90]: b8 to b11)
0: Command speed
1: Feedback speed
2: Automatic selection
When the speed control mode is switched to the position control mode, the command position immediately after the switching
is the current feed value at switching.
The following chart shows the operation timing for axis 1.
■RD77MS4 operation example
[Cd.138] Control mode switching request
[Cd.139] Control mode setting
[Cd.140] Command speed at
speed control mode
BUSY signal [X10]
[Md.26] Axis operation status
Control mode
([Md.108] Servo status1: b2, b3)
Zero speed
([Md.119] Servo status2: b3)
7 EXPANSION CONTROL
198
7.1 Speed-torque Control
Command speed to servo amplifier immediately after switching from position
control mode to speed control mode
The speed to servo amplifier immediately after switching is "0".
Motor speed received from servo amplifier at switching.
The command speed is invalid due to the setting of continuous operation to torque control mode.
At control mode switching, operation is the same as "0: Command speed".
V
Position control mode
30000
20000
6 to 11 ms
0 1
0
0
ON
OFF
0 30
[0, 0]
ON
Speed control mode
0
10
20000 30000 0
31
[1, 0]
OFF
Position control mode
t
6 to 11 ms
1 0
0
30 0
[0, 0]