Siemens S7-300 - Page 89

Machine and cam data
9.10 Machine data of the encoder
FM 352 electronic cam controller
Operating Instructions, 05/2011, A5E01071724-03
89
Baud rate
Address Name Type Initial value Comment
40.0 BAUD RATE DINT L#0 Baud rate
Range of values:
0 = 125 kHz
1 = 250 kHz
2 = 500 kHz
3 = 1000 kHz
With the "BAUDRATE" machine data, you define the data transfer speed between the SSI encoder
and FM 352.
This entry has no significance for incremental encoders.
The maximum cable length depends on the transmission rate:
 125 kHz → 320 m
 250 kHz → 160 m
 500 kHz → 63 m
 1000 kHz → 20 m
Count direction
Address Name Type Initial value Comment
59.0 CNT_DIR BOOL FALSE Count direction
0 = normal
1 = inverted
With the "count direction" machine data, you adapt the position feedback direction to the direction of
the axis movement. Also, take the rotation directions of all transmission elements into account (for
example, couplings and gears).
 Normal = ascending count pulses (incremental encoder) or encoder values (absolute encoder)
correspond to ascending actual position values
 Inverted = ascending count pulses (incremental encoder) or encoder values (absolute encoder)
corresponding to descending actual position values
It is not allowed to implement a lead time in combination with an absolute encoder (SSI) and inverted
count direction.