Safety Features - SICK T4000 Serie Instrucciones De Servicio

3
Chapter

WARNING
148
© SICK AG • Industrial Safety Systems • Germany • Subject to change without notice • 8012206/UC32/2010-11-15
System description
any faults that occur including internal device faults are
detected on the next request to close the safety contacts
(e.g. on machine start). The safety switch then switches to
the safe status. When errors are detected, the safety
circuit is switched off and the ERROR LED lights up. For
the T4000 Direct safety switch from date of manufacture
1037 (see 1.4 "Scope"), the error can be reset by opening
and closing the protective device for at least 2 seconds
each in most cases.
3.2

Safety features

The safety switch T40-E0121K has the following safety
features:
 up to category 4 in compliance with EN 13849-1,
 up to Performance Level PL e as per EN ISO 13849-1,
 up to SILCL3 as per EN 62061,
 proximity switch with switch monitoring type PDF-M in
accordance with EN 60947-5-3,
 redundant internal circuitry in the evaluation unit with
self-monitoring; as a result the guard remains effective
on the failure of a component,
 internal testing of the output state of the semiconductor
outputs on opening and closing the guard,
 cross-circuit detection using pulsed signals.
To estimate the PL of the complete system, a maximum
value of 100 years can be set according to the limit
value in EN ISO 13849-1:2008, section 4.5.2, for the
MTTF . This corresponds to a minimum value of the PFH
d
-8
of 2.47 x 10 /h.
With a series connection of up to 11 devices, these limit
values can be applied for the entire switch chain as a
partial system. As a partial system, the switch chain
reaches PL e.
When the simplified procedure per section 6.3 EN ISO
13849-1:2008 is used for validation, the performance
level (PL) may be reduced if more than 11 devices are
connected in series.
Operating Instructions
T4000 Direct Unicode
d