User Manual 08/2003 Edition

5
5 Description of the Functions 02.99 02.00 04.01
5.5 SIMODRIVE POSMO A functions
Referenced axis
when powering up
again
Behavior when
powering–down
5-150
Before SW 1.2, the following is valid:
If a referenced axis is switched-out, then it is still referenced after it has
been switched–in again if it was not moved when it was switched-out
(refer to ZSW.13 = 0).
The following is valid from SW 1.2:
Another behavior when the axis is switched–in again can be set using
P56 (operating options).
––> refer to Chapter 5.6.2 under P56
For axes with extremely low friction, it should be noted that a motor can
move into a preferred position when it is powered–down. Under worst
case conditions, this uncontrolled equalization motion is 11 degrees at
the motor shaft.
If the electronics power supply is simultaneously switched–out, then
this drive motion is not detected.
Possible counter measures include:
If there are separate electronics and load power supplies then the
electronics power supply must be switched–off with a delay after the
load power supply has been switched off.
The pulses should be cancelled before switching–off the load and
electronics power supply (e.g. using STW.1 = 0).
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SIMODRIVE POSMO A User Manual (POS1) – 08.03 Edition