Siemens SIMATIC Manual page 89

3.11 Digital input module SM 321; DI 16 x 24 VDC; with hardware and diagnostic interrupts (6ES7321-7BH01-0AB0)
Note
Wire break diagnostics
Wire break diagnostics is always used for one channel group with two channels. It is only
possible to determine that one of the two channels has suffered a wire break; it is not
possible to identify which one. When operated with PCS7, only one channel of the group can
be used at any time for an exact diagnosis.
Causes of error and troubleshooting
Table 3- 14 Diagnostics Messages of the SM 321; DI 16 x DC 24 V, causes of error and troubleshooting
Diagnostic message
Sensor supply missing
External auxiliary voltage
missing
Internal auxiliary voltage
missing
Fuse blown
Incorrect module parame-
ters
Watchdog timeout
EPROM fault
RAM fault
Hardware interrupt lost
Module not programmed
S7-300 Module data
Manual, 06/2017, A5E00105505-AJ
Possible cause of error
Overload at sensor supply
Short-circuit to M at sensor supply
Power supply L+ to module missing
Power supply L+ to module missing
Fuse blown in module
Fuse blown in module
Implausible parameter or combination thereof Program the module
Infrequent high electromagnetic interference
Module defective
Infrequent high electromagnetic interference
Module defective
Infrequent high electromagnetic interference
Module defective
The module can not output an interrupt, be-
cause the previous interrupt was not
acknowledged; possibly a configuration error
Startup error
To correct or avoid error
Eliminate overload
Eliminate the short-circuit
Feed supply L+
Feed supply L+
Replace the module
Replace the module
Eliminate the interference
Replace the module
Eliminate interference and cycle the power
supply of CPU off/on.
Replace the module
Eliminate interference and cycle the power
supply of CPU off/on.
Replace the module
Change interrupt processing in the CPU, and
reprogram the module as required
The error persists until the module is assigned
new parameters
Program the module
Digital modules
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