BECKHOFF BK3000 - Manual (Page 22)

Basic information
22 BK3xxx/LC3100
Fieldbus errors in the LC3100
I/O-RUN BF RUN Meaning Remedy
on off on Operating state: RUN
Inputs are read and outputs are set.
Everything is operating correctly
on on on,
blinking 1. Bus activity, but slave is not yet
parameterised
2. Bus error in which the outputs
a.) become 0
b.) remain unchanged
- Start master
- Check parameters
(-> Diagnostics data, BF-LED)
- Check configuration
(-> Diagnostics data, BF-LED)
off off on Terminal bus cycles synchronised
DP-watchdog switched off, no exchange
of data PLC is in STOP mode
off on off,
blinking No bus activity
- Start master
- Check bus cable
off on on Bus error, reaction
Terminal bus cycles are stopped - Start master
- Check parameters
(-> Diagnostics data, BF-LED)
- Check configuration
(-> Diagnostics data, BF-LED)
Run times and reaction times
Transfer of the signals from the input to the controller and from the
controller to the outputs requires a run time. This is composed of various
components. Transfer from the controller to the master, transfer through
the Profibus and transfer from the bus coupler to the outputs. This applies
analogously to the return distance.
Controller / Master
Please refer to the data provided by the master manufacturer for details of
the reaction time from the controller to the master. These times are
comparatively short and normally do not need to be considered.
The reaction time t
DP
on the Profibus is composed of the following. The
constants A, B and T
BYTE
depend on the baud rate.
7
T
DP
= Constant A
+ (Constant B + (Number of E/A-Byte x T
BYTE
)) [Slave 1]
+ (Constant B + (Number of E/A-Byte x T
BYTE
)) [Slave 2]
+ (Constant B + (Number of E/A-Byte x T
BYTE
)) [Slave 3]
+ ... [Slave ]
+ (Constant B + (Number of E/A-Byte x T
BYTE
)) [Slave n]
Baud rate Constant A
(in ms) Constant B
(in ms) T
BYTE
(in ms)
9,6 kBaud 64,5 25,6 1,15
19,2 kBaud 32,3 12,8 0,573
93,75 kBaud 6,6 2,62 0,118
187,5 kBaud 3,3 1,31 0,059
500 kBaud 1,6 0,49 0,022
1,5 MBaud 0,67 0,164 0,00733
3 MBaud 0,436 0,085 0,00367
6 MBaud 0,27 0,044 0,00183
12 MBaud 0,191 0,024 0,00092
i
Note
Pay attention to the special restrictions when using an ET200U or S5-95U
in one system. In certain circumstances, cycle times may be clearly
prolonged and more than 1.5 Mbaud is not possible.