SICK STR1

K2
K1
L–
+24 V DC
0 V
k2
k1
Reset
E217153/01/2020-01-29
R1 Y1 Y2 24A
2 14
S1 I1 I2 23A1 13
RLY3-OSSD2
State
RES
BN RD YE
BU GY PK WH
STR1
PLC
BN RD YE
BU GY PK WH
STR1
BN RD YE
B
U GY PK WH
I1 I2 I3
STR1
F2 F1
L+
Figure 9: 3 safety switches in series connection on safety relay
4.5 Thorough check concept
The safety switch must be tested by appropriately qualified safety personnel during
c
ommissioning, after modifications, and at regular intervals; see "Thorough check",
page 29.
Regular thorough checks serve to investigate the effectiveness of the safety switch and
discover defects resulting from modifications or external influences (such as damage or
manipulation).
The manufacturer and operating entity must define the type and frequency of the thor‐
ough checks on the machine on the basis of the application conditions and the risk
assessment. The process of defining the thorough checks must be documented in a
traceable manner.
4.5.1 Minimum requirements for regular thorough checks
The following thorough checks must be carried out at least once a year:
•
T
horough check of the principal protective function of the safety switch
•
Thorough check of assured sensing ranges S
ar
and S
ao
•
Thorough check for damage on the switch housing
•
Thorough check for damage on the switch cables
•
Thorough check for signs of misuse or manipulation on the safety switch
PROJECT PLANNING 4
8018754/12IU/2020-01-30 | SICK O P E R A T I N G I N S T R U C T I O N S | STR1
19
Subject to change without notice