Siemens SIMATIC ET 200AL System Manual page 631

Interrupts/diagnostics alarms
5.2 Interrupts
Hardware interrupt
The analog input module generates a hardware interrupt with the following events:
• Low limit 1 violated
• High limit 1 violated
• Low limit 2 violated
• High limit 2 violated
Detailed information on the event is available in the hardware interrupt organization block
with the instruction "RALRM" (Read additional interrupt information) and in the STEP 7 online
help.
The start information of the organization block includes information on which channel of the
analog input module triggered the hardware interrupt.
Note
Violation of two limits
If two limits are violated at the same time, limit 1 is always signaled first, followed by limit 2.
The figure below shows the assignment to the bits of the local data double word 8.
Figure 5-2
34
Start information of the organization block
Analog input module AI 4xU/I/RTD 4xM12 (6ES7144-5KD00-0BA0)
Equipment Manual, 08/2021, A5E32350124-AG