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Digital modules
8.6 SM 326; DO 10 x DC 24V/2A (6ES7326-2BF01-0AB0)
Fail-safe signal modules
Installation and Operating Manual, 01/2010, A5E00085586-10
155
Diagnostic message Error detection Possible causes of the problem
Corrective measures
CRC signature error General
CRC signature error during
communication between the CPU
and the module has occurred, for
example, due to electromagnetic
interference in excess, faults during
sign-of-life monitoring error, in case
of voltage drop or standard
program accesses F-SM.
Eliminate the
interference
Assigned monitoring time
exceeded
Check the monitoring
time parameters
Timeout of safety
message frame
monitoring
General
Startup of the fail-safe signal
module
—
Message frame
error
General
Sign-of-life and/or CRC signature
entered in the data message frame
Check the sign-of-life
and CRC signature
entries in the data
message frame for "0"
value