Siemens Simatic S7-300 - Behavior and Diagnostics of the SM 321; DI 16 X 24 VDC; Dependencies of Input Values on the Operating Mode of the CPU and Supply Voltage L+ of the SM 321; DI 16 X VDC; Diagnostic Messages of the SM 321; DI 16 X VDC

Digital Modules
3-29
Programmable Logic Controllers S7-300 Module Data
A5E00105505-03
3.9.3 Behavior and Diagnostics of the SM 321; DI 16 x 24 VDC
Effect of operating and mode supply voltage on the input values
The input values of the SM 321; DI 16 x 24 DC depend on the operating mode of
the CPU and on the supply voltage of the module.
Table 3-11 Dependencies of Input Values on the Operating Mode of the CPU and Supply
Voltage L+ of the SM 321; DI 16 x VDC 24
CPU Operating State Power Supply L+
to Digital Module
Input Value of Digital
Module
POWER ON RUN L+ exists Process value
L+ missing 0 signal
STOP L+ exists Process value
L+ missing 0 signal
POWER OFF – L+ exists –
L+ missing –
Diagnostic Messages of the SM 321; DI 16 x 24 VDC
The table below presents an overview of the diagnostic messages for the SM 321;
DI 16 x 24 VDC.
Table 3-12 Diagnostic Messages of the SM 321; DI 16 x VDC 24
Diagnostics Message
LED Scope of the Diagno-
stics
Parameters
can be
assigned
Sensor supply missing SF Channel group
Yes
Wire-break SF Channel group
Yes
Module not parameterized. SF Channel group
External auxiliary supply missing SF Module
Internal auxiliary power missing SF Module
Fuse blown SF Module
Incorrect parameter on module SF Module
No
Watchdog timeout SF Module
No
EPROM error SF Module
RAM error SF Module
Hardware interrupt lost SF Module