Siemens SIMATIC SM 335 Manual page 72

Data Exchange with the SM 335
External fault
Bit 2 is set in module diagnostic byte 1 when one of the following errors/faults oc-
curs:
• Measuring range module not connected
• Measuring range module not connected correctly (default parameters do not
match the measuring range module setting)
• External auxiliary power supply failed
• Fault on one of the inputs
– Common-mode error
– Open wire
– Measuring range violation (overrange)
– Measuring range violation (underrange)
• Fault on one of the outputs (ground short)
Channel error
If bit 3 in the module diagnostic byte has been set, the SM 335 has detected a
channel-specific error in one of the channels. You will find more detailed informa-
tion in the channel-specific diagnostics bytes (bytes 8 to 15).
No 24 V load voltage
Bit 4 in module diagnostic byte 1 is set when the 24 V load voltage has dropped
below 10 V.
SM 335 not initialized
Bit 6 in module diagnostic byte 1 is set when no parameters were assigned for the
SM 335.
Invalid parameters
Bit 7 in module diagnostic byte 1 is set when the SM 335 was incorrectly initialized,
that is, the parameters do not coincide with the measuring range module setting on
the SM 335. This bit is set if parameter assignment failed (e. g., when system func-
tion 55 WR_PARA is called to transfer the parameters).
3-34
SM 335 – High-Speed Analog Input/Output Module for the SIMATIC S7-300
6ES7 335-7HG00-8BA1