Siemens SINUMERIK 828D Function Manual page 1249

Supplementary conditions
• Linear axes with a traversing range > 4096 encoder revolutions, rotatory absolute value encoder EQN 1325
and a parameterized absolute value encoder range of MD34220 $MA_ENC_ABS_TURNS_MODULO = 4096:
- The maximum possible travel range corresponds to that of incremental encoders.
• Endlessly turning rotary axes with absolute encoders:
- Any number of integer transmission ratios are permitted.
- We recommend that you parameterize endlessly turning rotary axes with absolute encoders as modulo
rotary axes (traversing range 0...360 degrees).
MD34220 $MA_ENC_ABS_TURNS_MODULO
Otherwise, the machine axis may require a very long traverse path to reach absolute zero when the
measuring system is activated.
• Machine axes with absolute encoders:
- To ensure that the NC correctly determines the current actual position when the measuring system is
reactivated, the machine manufacturer / user must ensure that the machine axis is moved less than half
the assigned traversing range when the measuring system is deactivated (POWER OFF, "parking"
selected).
MD34220 $MA_ENC_ABS_TURNS_MODULO
Basic Functions
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
R1: Reference point approach
15.10 Supplementary conditions
1249