Interrupts - Siemens SIMATIC S7-1500 Manual

External errors, internal errors and malfunctions
● External errors occur outside the PS. In the parameterization, specify whether or not an
external error can trigger a diagnostic alarm. By default, external errors do not trigger
diagnostic alarms.
● Internal errors occur inside the PS. If still possible, an internal error always triggers a
diagnostic alarm.
● A malfunction is a static state; the PS must be sent in for repair. If still possible, a defect
always triggers a diagnostic alarm.
Explanation of the reactions
The PS is switched off retentively. Alarm is only generated if the PS is still powered by the
CPU or IM via the backplane bus. You cannot switch on the module unless you have
eliminated the error and disconnected power to the PS for approximately one minute.
5.3

Interrupts

What is a diagnostic interrupt?
You can determine reactions to internal or external errors in the user program, by
programming a diagnostic interrupt which interrupts cyclic program execution on the CPU
and triggers the diagnostic interrupt OB (OB82). The event which led to the interrupt is
entered in the start information of the OB82.
Trigger of a diagnostic interrupt
Events that can trigger a diagnostic alarm can also trigger a diagnostic interrupt:
● Supply voltage missing
● Overtemperature
● Overvoltage on the backplane bus
● Safety shutdown
● Switch position Off
● Malfunction
Reactions to a diagnostic interrupt
You can find the CPU reaction to a diagnostic interrupt in the function manual System
diagnostics (http://support.automation.siemens.com/WW/view/en/59192926).
Detailed information on the error event is available in the diagnostic interrupt OB by
executing the "RALRM" instruction (read additional interrupt information) and in the STEP 7
Online Help.
Power supply module PS 60W 24/48/60VDC HF (6ES7505-0RB00-0AB0)
Manual, 01/2019, A5E39450002-AB
Interrupts, diagnostic alarms, error and status alarms
5.3 Interrupts
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