LION I/O Modules
▪
Digital Outputs
53
10
Digital Outputs
The outputs are potential free semiconductor switches for the nominal voltage
range of DC 24 V…110 V.
10.1
Error Detection
10.1.1
Fail safe
10.1.2
Testpulse
SIL
relevant
LION-040
Following status can be diagnosis by the outputs:
▪ Switching status of the transistor
The voltage difference on fthe switching transistor is measured. With the
diagnosis it is possible to know if the transistor is working.
▪ Switching status of the output
Meausring of the voltage difference on the output terminals.
The PLC can detect the errors “Stuck at high“ (external voltage, capacity
load) and “Stuck at low“ (short circuit) with the help of the is status and the
switching status.
▪ Output errors
Overload, short circuit, overtemperature
These errors will occure in a switch off of the output channel (self protection).
▪ Recognization of external voltage supply on the plus switching output
If measuring the switching status on the transistor and output at the same
time, it can be detected if the error is internal an output module or the
application.
SIL
relevant
LION-039
▪ The fail safe of the modules is defined as logic “0“ (LOW).
▪ If an error occurs the corresponding status bit is set to “1“ and the process
value of the output is set to the defined safe value (“Stuck at high“).
▪ The outputs are switched off/inactive.
SIL
relevant
LION-041
All output signals, which are not in the safe mode are monitored cyclic with a test
pulse.
The testpulse is for detecting faults in the output circuit and ensures that the
output can write a “0“ signal.
The testpulse monitores the outputs for errors:
“Stuck at high“: The outputs“1“-signal is covered by a short “0“-signal of the
testpulse and read back.
The testpulse is 0.2 ms long. Between two testpulse is a time distance of 29 ms.
