2
0
2
0
-0
6
58
Troubleshooting
Evaluating Alarms in the TIA portal
If a diagnostics alarm is triggered, the user program in the TIA portal is interrupted and a diag-
nostics block is called. The following blocks are used:
The initial information regarding the cause and type of fault is provided by the OB called and its
start information. More detailed information regarding the error event can be obtained in the
error OB by calling RALRM_SFB [SFB54] (read supplementary alarm information). For this
purpose, SFB 54 must called in every error OB.
If the error OB called does not exist in the CPU, the CPU switches into the STOP operating
state.
The Structure of the Diagnostics Data Records
Block version 0x0101 and the format identifier (USI, User Structure Identifier) 0x8000 are used
to display the diagnostics data records.
The data values "ChannelNumber" and "ChannelError" contain the following values, depending
on the error that has occurred:
Cause
OB call
Diagnostics alarm (short circuit, overload, wire break, low voltage on an I/O
module)
OB82
Failure of a station or a rack
OB86
Type of error
Source of fault
Channel number
Error code
Undervoltage/overvoltage
of sensor/system power
supply
Module
0x8000 (diagnosis
not channel-spe-
cific)
0x0002
Auxiliary voltage/actuator
voltage too low
Auxiliary voltage
0x8000 (diagnosis
not channel-spe-
cific)
0x0103
Overload/short circuit of the
sensor supply
IO port (pin 1)
0x01 to 0x08
0x01
Port driver temperature
excess
IO port (pin 1)
0x01 to 0x08
0x0113
Overload/short circuit of the
digital 500 mA outputs
IO port (pin 4)
0x01 to 0x08
0x010A
Overload/short circuit of the
digital 2 A outputs
IO port (pin 2)
0x05 - 0x08
0x0109
Overload/short circuit of
auxiliary power supply
(U
Aux
) at Class B port
IO port (pin 2)
0x05 - 0x08
0x0108
IO-Link C/Q Error
IO port (pin 4)
0x01 - 0x08
0x0006
IO-Link device diagnosis
IO-Link device
0x01 - 0x08
Dependent on the IO-
Link device diagnosis
Extended diagnosis:
0x9000
