7 axis bus data error monitoring, Axis bus data error monitoring, 14 axis bus – Lenze 8400 TopLine User Manual
Page 846
14
Axis bus
14.2
Data transfer axis bus
846
Lenze · 8400 TopLine · Reference manual · DMS 6.0 EN · 06/2014 · TD05/TD14
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14.2.4.7
Axis bus data error monitoring
Operating mode
There are two error counters, one for incorrectly sent telegrams (
) and one for incorrectly
received telegrams (
• In an error-free normal operation, both error counters are = 0.
• Depending on the error type, the counters are increased by 8 in case of an error detection, and
reduced by 1 in case no error has occurred.
• If one of the two error counters is > 96, a warning is signalled via the LED AB-STATE (double
pulse).
• If an error counter increases or remains unchanged, a watchdog counter is increased in a 1-
ms cycle.
• If an error counter is reduced, the watchdog counter remains unchanged.
• If the error counters are = 0, the watchdog counter is reset to 0.
• If the watchdog counter reaches the monitoring time set in
• The error response set in
is activated (Lenze setting: "Fault").
• The error message "
" is entered into the logbook.
Parameterisation notes for "electrical shaft" application
When an "electrical shaft" is operated via an axis bus or generally via a bus system, data transfer
errors may occur due to e.g. EMC interferences. In order to prevent a mechanical offset of the drives
in case of a short-time interference only, the
function block should be used in the
slave drives. This function block has an internal correction mechanism which provides for an
automatic offset correction in case of a missing data telegram. The error monitoring can then be set
to an insensitive value (
= approx. 10 ... 30 ms) which results in a very robust transfer
system.
What happens in case of a cable break, loose contact or short circuit of the axis bus cable?
Such severe errors mostly cause a bus-off error in one or even several devices of the system.
• In this case as well, the data error monitoring is triggered.
• The "BusOff" state will be automatically reset after the time set in
has expired if the
error cause has been removed. Then, the axis bus changes to normal operation again.