The'' Position Reached" Message 2 - 5 - Siemens SIMATIC S5 Manual

Ready signals:
+24 V from the module to the power unit 5BxL+ x = (axis 1, 2, 3)
Ready input feedback of the 24 V from the power unit to the 1P BBx
Significance of the control signals:
The outputs "positioning pulses" and "direction" can be assigned parameters in the software.
Using the machine data "polarity", the active pulse edge and therefore also the inactive level and
the signal level for the direction of rotation can be selected, (See machine data "polarity".)
The output "reset" is used to disable the power unit when the axis is not installed, and to synchro-
nize the power unit and the module for a synchronized reference point approach, As long as
there is no machine data on the module, this output carries a high signal. As soon as there is
valid machine data on the axis, this output changes to low, At the beginning of the reference
point approach, a high signal is applied to this output for 100 ms. Providing the power unit has a
reset input, this synchronizes the power unit and the IP247.
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Note:
If the reference point approach is to be synchronized and the power unit does
not have a reset input, you must make sure that the module and power unit are
switched on and off at the same time. The IP247 assumes that the excitation pat-
tern counter of the power unit is at zero when it is switched on. This is always
the case after the power unit has been switched on or reset.
Ready signal BBx:
The power unit can be monitored for overload and power down via the digital input BBx. To do
this, you can loop the 24 V available at output BBxL+ via a floating contact of the power unit to
the input BBx. When the power unit is switched off, the contact must close.
2.8.2 The "Position Reached" Message
The "position reached" message is supplied both to the CPU as well as to a digital output. You
can find a detailed description of the "position reached" message in Section 2.7 "Axis Attributes",
Digital Inputs/Outputs and their Effects
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