4 Special Features Of The Safety-Related Semiconductor Outputs (Ossd); 5 Commissioning / Functional Test - ASO Safety Solutions ISK 77 Manuel D'utilisation

By applying an external voltage (value range 20 to 35 volt DC, 20 to 28 volt AC), an externally requested
test is performed according to the selected mode.
U
test
Upon actuation of switch sw, the test is requested and results in the deactivation of the outputs.
Without testing, the operation or wiring of device variant ISK 77 RT satisfies no specific safety
requirements.
9.4 Special feature of the safety-related semiconductor outputs (OSSD)
The electronic safety-related semiconductor outputs of the switching unit are constantly tested during
running operation. For this purpose, the output is cyclically switched off every 0.4 seconds for a period less
than 1 ms and the shut-down behaviour tested. These interruptions must not be evaluated by the higher-
-order controller as safety requests.
A primary controller should only evaluate the states of the output signal if the level is sustained for 5 ms. This
prevents pulses generated during a self-test while in the switched-on state and the testing of the switch-on
procedure from erroneously being processed as control information.
9.5. Commissioning / functional test
The plant / machine must be tested for proper function after all of the electrical connections have been
established and the supply voltage has been turned on.
• Actuate the sensors in sequence.
• Check the switching units for proper reaction.
The safety system must be professionally inspected at appropriate intervals. The inspection must be documen-
ted in such a way as to be comprehensible at all times. The requirements of the plant/machine manufacturer
are to be taken into account and followed.
sw
TST-SIG
TST-MOD
TST-COM
sw
TST-SIG
U TST-MOD
test
TST-COM
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