Siemens SIMATIC 500 Series Description And Operating Instructions page 39

Configuration
Data rate
1)
12 MBit/s
1)
6 MBit/s
1)
3 MBit/s
1.5 MBit/s
500 kBit/s
187.5 kBit/s
93.75 kBit/s
45.45 kBit/s
19.2 kBit/s
9.6 kBit/s
Table 3a: Constants for calculating the slot time at DP standard
(redundant optical ring)
Data rate
1)
12 MBit/s
1)
6 MBit/s
1)
3 MBit/s
1.5 MBit/s
500 kBit/s
187.5 kBit/s
93.75 kBit/s
45.45 kBit/s
19.2 kBit/s
9.6 kBit/s
Table 3b: Constants for calculating the slot time at DP/FMS ("universal")
and DP with S5 95U (redundant optical ring)
The calculation of the slot time only takes into consideration the optical network and the connection of bus sub-
scribers to the OLM via an RS 485 bus segment with a respctive length of max. 20 m. Longer RS 485 bus segments
must be allowed for by adding them to the Length
Note:
When the slot time is configured with a too small value the OLM will, through it's fault function and fault indications,
indicate such. The System-LED will blink red/green.
1)
Using the OLM/G11-1300 and OLM/G12-1300 at data rates of 12 MBit/s, 6 MBit/s, 3 MBit/s and 1.5 MBit/s the
minimum slot times according to the following table must be met.
Data rate
12 MBit/s
6 MBit/s
3 MBit/s
1.5 MBit/s
Table 4: Minimum slot time on OLM/G11-1300 and
OLM/G12-1300
Use the values from Table 4 if the calculated slot time is smaller than the minimum slot time indicated in the table.
32
a b
1651 240
951 120
551 60
351 30
251 10
171 3.75
171 1.875
851 0.909
171 0.384
171 0.192
a b
1651 240
951 120
551 60
2011 30
771 10
771 3.75
451 1.875
851 0.909
181 0.384
171 0.192
OF
Minimum slot time
3800 t
Bit
2000 t
Bit
1000 t
Bit
530 t
Bit
6.2 Configuration of redundant optical rings
c
28
24
24
24
24
24
24
24
24
24
c
28
24
24
24
24
24
24
24
24
24
.
Version 2.1 10/01