Siemens SIMATIC User Manual

Digital modules
3.12 Digital input module SM 321; DI 16 x DC 24/125 V; with hardware and diagnostic interrupts (6ES7321-
7EH00-0AB0)
S7-300 Module data
100 Manual, 06/2017, A5E00105505-AJ
Special features of diagnostics
The SM 321; DI 16 x DC 24 V/125 V supplies 9-byte diagnostic data (diagnostic data set 0
with a length of 4 bytes and the diagnostic data set 1 with a length of 9 bytes).
The wire-break diagnostics is only reported in the channel error vector of the data set 1
(bytes 7 and 8). Each channel that reports an error in the channel errror vector has a wire-
break. You can find additional information, in chapter Structure and content of diagnostics
data, byte 0 and up (Page 584).
Causes of error and troubleshooting
Table 3- 20 Diagnostics messages of SM 321; DI 16 x DC 24 V/125V, causes of error and troubleshooting
Diagnostic message
Possible cause of error
To correct or avoid error
Incorrect module parame-
ters
Implausible parameter or combination thereof Program the module
Time monitoring activated
(watchdog)
Infrequent high electromagnetic interference Eliminate the interference
Module defective
Replace the module
EPROM fault Infrequent high electromagnetic interference Eliminate interference and cycle the power
supply of CPU off/on.
Module defective
Replace the module
RAM fault Infrequent high electromagnetic interference Eliminate interference and cycle the power
supply of CPU off/on.
Module defective
Replace the module
Hardware interrupt lost The module can not output an interrupt, be-
cause the previous interrupt was not
acknowledged; possibly a configuration error
Change interrupt processing in the CPU, and
reprogram the module as required
The error persists until the module is assigned
new parameters
Module not programmed
Startup error
Program the module
3.12.3 Interrupts of SM 321; DI 16 x DC 24/125 V
Introduction
This chapter describes the interrupt reaction of SM 321; DI 16 x DC 24 V/125V. Always
distinguish between the following interrupts:
● Diagnostic interrupt
● Hardware interrupt
For detailed information on the OBs and SFCs mentioned below, refer to the STEP 7 Online
Help.

Siemens SIMATIC Specifications

General

Product type designation	SIMATIC
CPU	Varies by model
Memory	Varies by model
Input/Output	Varies by model
Communication	Varies by model
Programming Language	STEP 7
Operating Temperature	0°C to 60°C (varies by model)
Protection Class	IP20
Category	Programmable Logic Controller (PLC)