Mitsubishi Electric MELSEC-Q QD75M, User Manual

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MELSEC-Q
5 DATA USED FOR POSITIONING CONTROL
(3) Precautionary notes
(a) The difference between the last command position when the servo turned
OFF and the present value when the servo turned ON, is output at the
first operation of restart. If the restart allowable range is large at this time,
an overload may occur on the servo side.
Set the "restart allowable range when servo OFF changes to ON" to a
value where the mechanical system will not be affected by a signal
output.
(b) The restart servo OFF changes to ON is valid only for the first time servo
OFF changes to ON. From the second time servo OFF changes to ON,
the setting for restart allowable range when servo OFF changes to ON is
disregarded.
(c) Execute servo OFF when the mechanical system is in complete stop
state. The restart when servo OFF changes to ON cannot be applied to a
system in which the mechanical system operated by external pressure or
other force while the servo is OFF.
(d) Restart can only be executed while the operating status of the axis is
"stop". Restart cannot be executed when the operation status of the axis
is other than "stop".
(e) Do not restart while a stop command is ON.
If restart is executed while stopped, an error (error code 106: Started
during stop command ON) is generated, and the operating status of the
axis becomes "ERR".
Therefore, restart cannot be performed even if the error is reset.
(f) Restart can also be executed while the positioning starts signal is ON.
However do not set the positioning start signal from OFF to ON while
stopped.
If the positioning start signal switches ON from OFF, positioning is
performed from the positioning data number set in the buffer memory at
1500 or from the positioning data number of the specified point.
(g) If positioning is terminated by a continuous-operation interrupt request,
restart cannot be performed.
If a restart request is made, a warning (warring code 104: Restart
disabled) is generated.
[Operation at the time an emergency stop is input] [Operation when a restart is performed]
Emergency stop input
(Last command position)
Stop position at the
time of servo OFF
Movement while
servo is OFF
Restart operation
Last command
position
Output once at
the time of restart
(Present value time of servo ON)
Stop position at time of servo OFF