
A
A-24
User manual IC220SDL953 - September 2011
GFK-2731
A 8
Diagnostics
In addition to precise diagnostics for the standard bus system, the safe input and output
devices also support the detection of I/O errors and device errors.
A 8.1
Error detection in I/O devices
Safe inputs
Depending on the device type and parameterization, the following errors can be detected
at safe inputs:
– Short circuit
– Cross circuit
– Overload/short circuit of the clock outputs
When an error is detected at an input, the safe state is set for this input and a "0" is
transmitted in the input data of the input ("0" = safe state).
The corresponding error message is transmitted to the IC220SDL953 and the standard
controller.
Safe outputs
Depending on the device type and parameterization, the following errors can be detected
at safe outputs:
– Short circuit
– Cross circuit
– Overload
– Violation of the shutdown time
When an error is detected at an output, the affected output is disabled ("0" = OFF = safe
state).
The corresponding error message is transmitted to the IC220SDL953 and the standard
controller.
For more detailed information about error detection at safe inputs, please refer to the user
manual for the IC220SDL543.
For more detailed information about error detection at safe outputs, please refer to the
user manual for the IC220SDL... modules.