Meanings Of Bus Parameters - Siemens SIMATIC S5 Manual

Parameterizing, saving and documenting the configuration with COM ET 200 Windows
8.2.1 Entering bus parameters
Definition You use the bus parameters to define:
Meanings
The meanings of the individual bus parameters are shown in Table 8-2.
Table 8-2 Meanings of bus parameters
Designation
Bus designation Assign a name to the bus system. Max. length: 40 characters.
1
Bus profile In the "Bus profile" field, you can select certain bus and reaction times:
PROFIBUS-DP, if
– there is at least one IM 308-C in the bus
and/or
– only DP masters on the bus and they comply with DIN E 19245, Part 3.
DP/FMS,
if there is at least one FMS master on the bus.
DP with IM 308-B,
if there is at least one IM 308-B or one CP 5480-DP (version 2) on the bus,
but no FMS master.
Variable / S5-95U, if you have an S5-95U as DP master or the bus or reac-
tion times have to be varied to suit special circumstances (with "Set parame-
ters ...").
The defaults apply to the S5-95U (DP master).
Baud rate Set a baud rate between 9.6 kbaud and 12000 kbaud. Bear in mind that some
DP slaves are restricted to a maximum of 1500 kbaud (e.g. ET 200U).
Repeaters on bus Use this parameter to tell COM ET 200 Windows whether the bus is extended
by RS 485 repeaters or fiber–optic amplifiers (e.g. OLMs or star hubs).
If the bus is extended, the hamming distance is reduced from 4 to 2 at baud
rates of 3000 kbaud or higher.
Set parameters ... In the "Set parameters" dialog box, you can define among other things:
the response monitoring time (response monitoring/T
the bus as a function of the target rotation time.
If, for example, you select a factor of 1.25, the response monitoring time is
1.25 times the target rotation time.
The target rotation time Ttr, if, for example, you want to make provision for
a second other-vendor master.
1
: RESET the DP slaves not incorporated in the bus after a bus-profile change.
ET 200 Distributed I/O System
EWA 4NEB 780 6000-02a
the designation for the bus system
the bus profile for transmitting data on the bus
the baud rate
whether the bus incorporates an RS 485 repeater, and
the duration of the response monitoring time.
Meaning Default
–
PROFIBUS-
DP
1500 kbaud
no
–
) for all DP slaves on
tr
8
8-7