Plc Data Block (Db18) - Siemens SINUMERIK 840D sl Function Manual

Data descriptions
9.6 Interface signals
Fault, data transfer
This signal is used to diagnose the cause for the set signal "communication error".
1 signal: There is a CRC error
0 signal: There is no CRC error
Acknowledgment, communication failure
It is possible to acknowledge faults that are displayed via the "communication failure" bit using
the "acknowledgment communication failure" signal. This acknowledgment must be made in
the same OB1 cycle as when the "communication failure" signal occurred as 0/1 edge.
Setting the acknowledgment
When setting the acknowledgment, the user assumes the responsibility of providing suitable
substitute values for the SGA of the drive, as these are no longer valid. The user must bring
the machine into a safe state.
If the acknowledgment is not made after an OB1 cycle, then the frozen SGA are changed over
from the drive to deleted SGA and the diagnostics bit "Communication failure was not
acknowledged" is set. If the acknowledgment is made within an OB1 cycle, the SGA of the
drive remain frozen and the diagnostics bit "Communication failure was not acknowledged" is
not set. There is no further response.
The fault situation can only be executed with POWER ON.
Communication failure was not acknowledged
Indicates whether a fault displayed using bit "Communication failure" was acknowledged using
the bit "Acknowledge communication failure":
0: Communication has not failed or a communication failure was acknowledged.
1: Communication has failed and this was not acknowledged.
9.6.3

PLC data block (DB18)

Parameterization part
DB18
Data block
Byte Bit 7
DBB 0 8th input
byte
486
WARNING
Signals for safety SPL
Bit 6 Bit 5
7th input 6th input
byte byte
Interface PLC → PLC
Bit 4 Bit 3
INSEP valid (valid bit)
5th input 4th input
byte byte
Function Manual, 12/2017, 6FC5397-4BP40-6BA1
Bit 2 Bit 1
3rd input 2nd input
byte byte
Bit 0
1st input
byte
Safety Integrated