3. SCON-CA/CF
A
137
(26) Load output judgment (LOAD) PLC input signal
This signal is available only in the pressing operation.
When this signal is used for pressing-in purpose, it should be known if the set load threshold is reached
during the pressing operation.
The load threshold and check range are set by the PLC and the LOAD signal will turn ON when the
command torque (motor current) exceeds the threshold inside the check range.
This signal judges the load output based on the fact that the command torque exceeds the threshold for the
specified time period.
This processing procedure is the same as for the pressing judgment. The judgment time period can be
changed freely using the parameter No. 50 “Load Output Judgment Time Period”.
This signal is continued until the next movement command is received.
x
Set the pressing speed using the parameter No. 34 “Pressing Speed”.
When the machine is delivered, it has been individually set depending on the actuator characteristics.
Set an appropriate speed considering the work part material and shape.
x
Set the parameter No. 50 “Load Output Judgment Time Period”.
x
Set the parameter No. 51 “Torque Inspected Range” to “0” (enabled).
x
Set the threshold inspected width using the PLC's Zone Bo Register or Zone Boundary -
Register.
x
Set the threshold using the PLC's Load Current Threshold Register.
x
Set the positioning band using the PLC's Positioning Band Register.
Set it a bit longer from the backmost position considering the mechanical dispersion of the work part.
Refer to the operation manual for the controller for more information.
Caution:
x
If the actuator pushes against the work part before the target position, it is regarded as a
servo-motor error.
Take care of the positional relationship between the target position and the work part
position.
x
The actuator continues to push the work part with the pressing current at the stop time
decided with the current-limiting value.
It is not the stop condition, so take the greatest care to deal with it.
Position where this signal is turned ON
when the command torque exceeds the
threshold within the torque inspected
width range
Crack range
Speed
Travel
Target position
Position where the actuator is pushed
against the work part and the pressing
completion is judged so the positioning
completion signal is turned “ON”
Positioning band (max. pressing level)