EUCHNER CES-AZ-UBS-01B (Multicode) - Manual (Page 15)

Operating Instructions Safety System CES-AZ-UBS-01B
15
Self-test with test input TST
On electromechanical safety switches or magnetic switches, the function test can
be performed by cyclically opening the safety guard. From category 2 according
to EN ISO 13849-1 and in accordance with EN 60204-1 : 1997 (sec. 9.4.2.4), a
function test must be performed on the entire safety system on start-up or after
defined intervals.
Testing of the internal function of the device is not necessary because the device
monitors itself in real time. Welding of an output contact (relay output) is detected
by the device at the latest the next time the safety guard is opened. A short circuit
in the output cable is not detected by the device.
In addition, the entire safety circuit can be tested without opening the safety guard.
For this purpose, opening of the safety guard can be simulated by applying
DC 24 V to the test input TST.
The safety outputs are switched off, enabling testing of the complete safety circuit.
The diagnostic output ERR on the evaluation unit is also set HIGH as a monitoring
function.
When the test input TST is reset, the evaluation unit resets the diagnostic output
ERR to LOW, the red LED switches off and the safety outputs are switched on again.
This permits self-testing of the safety system without opening the safety guard.