Siemens SIMODRIVE 611 universal - Page 301

5
5.8 Motion Control with PROFIBUS–DP (from SW 3.1)
5-301
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SIMODRIVE 611 universal Description of Functions (FBU) – 04.05 Edition
Table 5-37 Time settings for ”DP slave 611U”, continued
Name DescriptionLimit valueValue
1)
T
DX
E10
hex
 3600
dec
T
DX
< T
DP
Data exchange time
This is the time which is required to transfer, within one
DP cycle, the process data to all of the slaves.
T
DX
= integer multiple of T
Bit
T
Bit
= 1/12 µs at 12 Mbaud
Calculation: T
DX
= 3600  T
BIT
= 300 µs
T
PLL_W
0 – PLL window
(half the window width of the GC synchronizing window)
The following applies to the setting:
 Small window ––> minimization of synchronization
fluctuations on the drive
 Large window ––> larger tolerance with respect to
GC fluctuations
Calculation: (assumption: T
PLL_W
= A
Hex
 10
Dec
)
T
PLL_W
= 10  T
BIT
= 0.833 µs
T
Bit
= 1/12 µs at 12 Mbaud
Recommendation: Set T
PLL_W
to 0 (standard value)
––> the ”DP slave 611U” then automatically uses the
standard value of 0.81 µs
T
PLL_D
0 – PLL dead time
The PLL deadtime can be used to compensate for differ-
ent data transfer times to the slaves (e.g. due to the use
of repeaters).
The slaves with faster transfer times are delayed with a
corresponding PLL dead time.
Calculation: T
PLL_D
= 0  T
BIT
= 0 µs
T
Bit
= 1/12 µs at 12 Mbaud
1) The values correspond to the master device file SIEM808F.GSD
5 Communications via PROFIBUS DP
08.99