Siemens SIMATIC S7-400 Reference Manual page 225

Causes of errors and remedies for analog input modules
Table 5-44 Diagnostic messages of the analog input modules, causes of errors and remedies
Diagnostic message
Module error
Internal error
External error
Channel error
External auxiliary voltage
missing
Front connector missing
No module parameters
Incorrect parameters
Channel information availa‐
ble
Measuring range module
incorrect/missing
STOP mode
EPROM error
RAM error
ADC/DAC error
Hardware interrupt lost
Configuration / program‐
ming error
Short-circuit to M
Wire break
S7-400 Automation System Module Data
Reference Manual, Ausgabe 11/2016, A5E00850736-08
Possible cause of error
Any, the module has detected an error.
Module has detected an error within the au‐
tomation system.
Module has detected an error outside of the
automation system.
Indicates that only certain channels are faul‐
ty
Load voltage to supply the 2-wire transduc‐
er is missing on terminals L+ and M.
Jumper between connections 1 and 2 in the
front connector is missing.
Module requires information whether it
should operate with default system param‐
eters or with your parameters.
A parameter or combination of parameters
is incorrect; impermissible measurement
range, for example.
Channel error; module can provide addi‐
tional channel information.
One or more measuring range modules is
missing or incorrectly inserted
No parameters have been assigned to the
module and the first module cycle has not
been completed.
Module is defective
The module cannot send an interrupt, since
the previous interrupt was not acknowl‐
edged; possible configuration error.
Illegal parameters transferred to module
A short-circuit to the M potential has occur‐
red on the sensor supply of 2-wire trans‐
ducers.
Resistance of transducer circuit too high
Open circuit between module and sensor
Channel not connected (open)
5.17 Diagnostics functions of analog modules
Remedy
-
-
-
-
Connect supply L+
Install jumper
Message present after power on, until the CPU
has completed the transfer of parameters; config‐
ure the module as required.
Reassign parameters to the module
-
Insert the measuring range modules on the mod‐
ule according to the parameter assignment of the
type of measurement and the measurement
range
If a reboot of the CPU all the digitized analog val‐
ues are in the intermediate memory, this mes‐
sage is reset
Replace the module
Change the interrupt handling in the CPU
(change priority for interrupt OB; shorten interrupt
program).
Check the measuring range module
Reassign parameters to the module
Eliminate the short-circuit.
Use a different type of transducer, or modify the
wiring, for example, using a larger conductor
cross-section.
Connect the cable
Disable channel ("Measuring type" parameter)
Wire the channel
Analog modules
225