Festo CMMP-AS-***-M3 Series, Описание

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6 Functions
28 Festo – GDCP-CMMP-M3-FW-EN – 1203NH
If the actual value exceeds the lower limit of the interval, it assumes the upper limit value.
If the actual value reaches the upper limit of the interval, it displays the lower limit value.
The lower limit of the interval is contained in the range of values; the upper limit does not
belong to this, i.e. the highest value is never shown, as it is physically at the same posi-
tion as the lowest value. Example: An interval of precisely one revolution is to be defined:
Incorrect: 0 R … 0.99999 R
Correct: 0 R … 1 R.
Note
setpoints outside the interval (incl. the upper interval limit) are always approached
again, even if the drive is already at the position.
Note
When the cam disc function is activated, modulo positioning can only be used for the
master.
6.2 Homing
No homing is required for speed-controlled operation or force/torque operation.
For absolute positioning, homing must be executed and the dimensional reference sys-
tem defined at initial commissioning. If the drive does not use a multi-turn absolute en-
coder, homing must be repeated at each switch-on or reset.
To be able to travel to an absolute, unique position in the positioning range, the drive must be refer-
enced to a measuring reference system.
Homing of the drive comprises:
– Homing
– Establishment of the axis zero point
– Definition of the dimensional reference system.
With homing, the correct zero position is determined by means of a reference signal. The reference
signal trigger defines the reference point of the dimensional reference system. The reference point is
the absolute point of reference for the axis zero point. In the factory setting, the axis zero point = pro-
ject zero point.
The reference signal supplies, for example, a switch that is triggered at a known, unique position on the
travel path. Also, dependent on the motor encoder, additional signals (e.g. encoder zero track) can be
evaluated to increase accuracy. You establish the used signals via the homing method.