Deactivating The Test Pulses At The Outputs; Single-Channel Use Of Outputs - Leuze electronic MSI 400 Operating Instructions Manual

3.4.5

Deactivating the test pulses at the outputs

It is possible to deactivate the test pulses at one or more output pairs. The outputs of a MSI 410 module
are combined into two output pairs. Q1/Q2 and Q3/Q4. The test pulses each act upon the two outputs of an
output pair.
Switching off the test pulses at one of the two outputs of an output pair will switch off the
test pulses of the entire output pair!
Deactivating the test pulses at one or more safety outputs of a MSI 4xx module reduces the
safety parameters of both safety outputs of the respective output pair of this module.
Ä Be aware of this in order to ensure that your application corresponds to an appropriate risk
analysis and risk avoidance strategy.
Ä You can find more detailed information on the safety parameters here: Safety technology
reference values [chapter 12.2]
Be sure to use protected or separate cabling!
Ä If you deactivate the test pulses at one or more safety outputs, short-circuits at other output
circuits cannot be detected. This affects the safety function!
Ä In the event of a short-circuit after 24 V, it will no longer be possible to switch off the output.
Furthermore, it will not be possible to prevent reverse current from going into a switched-off
output, which will influence the capability of switching off the outputs.
Carry out cyclic tests when the test pulses at one or more safety outputs are deactivated!
Once you deactivate the test pulses at one or more safety outputs, conduct the following tests
once a year:
Ä Switch off all of the safety outputs without test pulses simultaneously for at least one second
via the logic program of the controller module.
OR
Ä Restart the MSI 400 system by switching off the supply voltage.
You will thus deactivate the test pulses at an output of a MSI 400 module:
Ä Connect an output element to the MSI 4xx module.
Ä Using the right mouse key, click on the output element and select the Edit.... command in the context
menu.
Ä Deactivate the Activation of test pulses of this output option.
The test pulses of this output will be switched off. A corresponding note will be displayed in the hard-
ware configuration area under the respective MSI 4xx module.
3.4.6

Single-channel use of outputs

Be sure to consider a potential brief switch to high with single-channel safety outputs!
In the event of an internal hardware error, single-channel safety outputs can switch to high once
for 10 ms after the error has been detected.
Ä Consider this during your risk analysis and reduction strategy.
Otherwise, there is a hazard for the operator of the machine.
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WARNING
WARNING
WARNING
WARNING
MSI 400
Product description
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