Operating Instructions
T4000
8009704/US09/2010-12-20
Commissioning and operation
6.4
Function test (self-test)
In case of T4000 safety switches the function test
can be performed by cyclically opening the protec-
tive device.
On start-up or at defined intervals, the entire safety
system must be subjected to a function test in ac-
cordance with EN 60204-1.
The internal functioning of the T4000 safety switch
does not need to be checked because the device
monitors itself in real time. The fusing of an output
contact (relay output) will be detected at the very
latest when the safety guard is next opened. A cross
fault along the output line is not detected by the
device. Furthermore, the entire safety circuit can be
tested without opening the safety guard. This is
done by applying 24 V DC to the test input to simu-
late opening of the safety guard.
The safety outputs are disabled so that the entire
safety circuit can be tested. As a monitoring func-
tion, the diagnostic output ERR is also set to HIGH
by the evaluation unit.
When the test input is reset, the diagnostic output
ERR is set back to LOW by the evaluation unit, the
red LED goes out and the safety outputs are
switched on again.
This allows the safety system to test itself without
the safety guard having to be opened.
© SICK AG • Industrial Safety Systems • Germany • Subject to change without notice
6
Chapter
165