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03.00 | MEG 64 EC | Assembly and Operating Manual | en | 389203
5.4 Position mode
In order to attain an economical cycle time in an automation
process, we recommend prepositioning the claw jaws. This means
that the gripper is moved to a position that is minimally
"larger" (with O.D. grippers) or "smaller" (with I.D. grippers) than
the workpiece to be gripped. For this purpose, the "position
mode", i.e. step mode is used. The distance the gripper is to cover
from the current position towards "open" or "closed" is in this
mode specified by "Analog input: Position" (terminal 23) or by
"Pos." potentiometer (potentiometer P3).
This means that the stroke that the gripper performs depends on
the analog voltage value that is present at the input or the
potentiometer. This analog value must be present prior to
execution of the "Gripper open" or "Gripper closed" command.
If the gripper moves to an end position or onto a workpiece in
position mode, the current movement command is reset and the
gripper stops. The superordinate control unit only receives the
digital signal "Gripper stopped" (terminal 13), but not the "Target
position reached" signal (terminal 18).
MEG 64 EC achieves a relative positioning accuracy of 0.1 mm. This
is the accuracy with which a stroke specified by the potentiometer
or the analog input is moved from the current position, if no step
loss occurs due to collision of the claw jaws with a workpiece or
the like.