Siemens Sinamics S120 Function Manual page 372

Maintenance
9.4 Message buffer
When a safety message is present, bit r2139.5 is set to 1 ("safety message active"). The
entry in the message buffer is delayed. For this reason, the message buffer should not be
read until a change in the buffer (r9744) has been detected after "Safety message present"
is output.
The messages must be acknowledged via a fail-safe input F-DI of the TM54F/CU310-2 or
via PROFIsafe.
P roperties of the safety message buffer:
● The entries appear in the buffer according to the time at which they occurred.
● If a new message case occurs, the message buffer is reorganized accordingly. The
history is recorded in the "Acknowledged message case" 1 to 7.
● If the cause of at least one message in "Current message case" is rectified and
acknowledged, the message buffer is reorganized accordingly. Messages that have not
been rectified remain in "Current message case".
● If "Current message case" contains 8 messages and a new message for the current
message case is output, the message in the current message case parameters is
overwritten with the new message in index 7.
● r9744 is incremented each time the message buffer changes.
● A message value (r9749, r9753) can be output for a message. The message value is
used to diagnose the message more accurately (refer to the message description for
more details).
Deleting the message buffer:
The message buffer can be deleted as follows: p9752 = 0. Parameter p9752 (SI message
cases, counter) is also reset to 0 at POWER ON. This also clears the fault memory.
Ov erview of important parameters (see SINAMICS S120/S150 List Manual)
• r2139.0...15
• r9744
• r9745[0...63]
• r9747[0...63]
• r9748[0...63]
• r9749[0...63]
• r9750[0...63]
• p9752
• r9753[0...63]
• r9754[0...63]
• r9755[0...63]
• r9756[0...63]
372
CO/BO: Status word, faults/alarms 1
SI message buffer changes, counter
SI component
SI message code
SI message time received in milliseconds
SI message value
SI diagnostic attributes
SI message cases, counter
SI message value for float values
SI message time received in days
SI message time removed in milliseconds
SI message time removed in days
Function Manual, (FHS), 07/2016, 6SL3097-4AR00-0BP6
Safety Integrated