JVL MAC050, User Manual

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JVL Industri Elektronik A/S - User Manual - Integrated Servo Motors MAC050 - 800 55
2.10 Power Save
2.10.1 Power Save
The MAC50-141 firmware supports a function to save power in Position mode and An-
alogue bi-position mode that can automatically set the motor into Passive mode during
pauses in movements, and restore the original mode when a new movement is required.
This can be useful for battery powered applications as well as general power and cost
savings and to reduce audible and electrical noise.
The power save function is enabled when bit 0 in register 180, SETUP_BITS, is set to
one.
When Power Save is enabled, the motor is set into Passive mode after the actual position
has been within the In Position Window for one second. This position, where Passive
mode was entered, is then remembered, and as soon as the actual position gets farther
from the remembered position than the value in the In Position Window register, the
motor is set back into the original Position or Analogue bi-position mode.
Cautions.
When Power Save is enabled, some functions may work differently from what is expect-
ed. For instance, in Analogue bi-position mode, changing the Low or High Position values
will not have effect until the motor is set back into active mode by turning the axis or re-
selecting the active mode.
Also with under-voltage conditions, where the motor is set to enter Passive mode and
restore the original mode when the voltage gets back to normal, can leave the motor in
Passive mode, so in this case under-voltage handling should rather set an error bit that
should be monitored.
In some tricky cases, when the motor is Power Saved and the axis turns very slowly away
from the saved position, the motor will stay in Passive mode until the actual position has
moved twice the distance that is stored in the In Position window register. This happens
because the motor initially wakes up at the correct distance, but will re-enter Passive
mode immediately because it was not outside the In Position window long enough to
resume the original active mode. This issue can be reduced by selecting a better value
for the In Position window register.
Only MAC050 to 141