Pfannenberg 23106100601, Инструкция по эксплуатации/Руководство по безопасности

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1
Requirement
Diagnosis
channel
4 Warning signal 3
Warning device
Action
(Mensch)
6
5
Safety-
relay
Control
2
Machine
start
7
4.4. Evaluation
4.4.1. Use as a starting alarm of machines
For use as a starting alarm of machines, the function of the generation of the acoustic warning signal in the sounder
channel is to be assessed as a function of the machine. The safe condition is reached when the acoustic warning sys-
tem works reliably. The diagnosis channel tests and monitors this function and, upon failure, leads in the safe condi-
tion via a safety loop. This architecture is illustrated schematically in
Fig. 5 .
Starting alarms and similar uses are architectures that can normally be attributed to the 'high demand mode'. Immedi-
ately before switching on the machine or entering the dangerous condition, an automatic function test must be carried
out by a superior control system, such as described in section
4.8 . Only after a successful test can there be an ap-
proval. Test functions in the superior control system and corresponding measures for fault messages must be in ac-
cordance with the functional safety according to IEC/EN61508.
The safety loop is composed of a diagnosis channel with detection (4), evaluation of the hazardous state (2) and
elements of the machine control system (5) for triggering the test function and for reaching the safe status. The
elements of the machine control system (2 and 5) were not considered in the analysis.
Fig. 5 Starting alarm
Fig. 6 Safety relevant block diagram
PFH 3,9 x 10
-9
1/h
SFF 99 %
DC 94,9 %
MTTFd >100 years
λ
DU
diagnosis circuit 4 Fit
λ
DD
diagnosis circuit 73 Fit
λ
S
diagnosis circuit 7459 Fit
HFT 0
Architecture type IEC/EN61508 B
Suitability of the system for use in safety chains until 2
Category (DIN EN ISO13849) 2
PL (DIN EN ISO13849 d
4.4.2. Use as acoustic warning system when hazardous statuses are detected
When used as a warning system following the detection of hazardous statuses, the generation of an acoustic warning
signal must be assessed as a safety function.
A measurement records a dangerous condition and introduces the safe condition by controlling the acoustic warning
system (personnel/operator is warned).
Note: The warning of people is a voluntary measure as it requires willing handling of one or more people. This archi-
tecture only corresponds to the requirements of the European Machinery Directive if, according to state-of-the-art
technology, no constructive safety or other voluntary measure is possible to reach a safe condition.
Diagnosis Control Safety relay