Efficient Networks S120 manual Configuration of the load gear p2720, Position tracking p2721 =

Function modules 7.8 Closed-loop position control

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Figure 7-10 Position tracking (p2721 = 24)

In this example, this means:

Without position tracking, the position for +/- 4 encoder revolutions about r2521 = 0 LU can be reproduced.

With position tracking, the position for +/- 12 encoder revolutions (+/- 12 load revolutions with load gearbox) can be reproduced (p2721 = 24).

Practical example:

For a linear axis, the value for p2721 is set to 262144 for an encoder with p0421 = 4096. That means, +/- 131072 encoder revolutions or load revolutions can be reproduced in this way.

For a rotary axis, a value for p2721 = p0421 is set for an encoder.

Configuration of the load gear (p2720).

The following points can be set by configuring this parameter:

●p2720.0: Activation of position tracking

●p2720.1: Setting the axis type (linear axis or rotary axis)

Here, a rotary axis refers to a modulo axis (modulo offset can be activated through higher-level control or EPOS). With a linear axis, position tracking is mainly used to extend the position area (see section: Virtual multiturn encoder (p2721)).

●p2720.2: Reset position

Note

If position tracking of the load gearbox is activated after an adjustment p2507=3 has been made, the adjustment will be reset.

Another adjustment will reset the position (overruns).

Position tracking can be activated in the FW2.5 SP1 only for a single DDS.

If multiple DDS are configured, it will not be possible to active the position tracking function.

Drive Functions	243
Function Manual, (FH1), 07/2007 Edition, 6SL3097-2AB00-0BP4