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Yaskawa MotionWorks IEC User Manual

Page 180

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PLCopenPlus Function Blocks for Motion Control 2013-04-13

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With the second example we use opposite signs for Direction & Torque
(e.g. Retention or brake control). (In the FB: +Direction –Torque). It is
like an unwinding application with torque on the material, and a break in
the material. When the material breaks, as shown in the middle of the
picture, this causes a drop in the Real Torque (in absolute terms): the
velocity will decrease, limited by the fastest “deceleration” limit specified
by the “Deceleration” VAR_INPUT down to zero velocity (with no tension
there is a risk of having shock breakings, so we have to limit to the
fastest). In this case the torque setpoint might not be achieved.