S5-95F Failsafe Mini PLC
S5-95F
Quality Levels to DIN V 19250
The classification to DIN 19250 is not based on existing regulations but rather uses risk parameters
to define the risk inherent in a process. Risk parameters are the degree of damage, duration of stay
in hazardous areas, the possibility of avoiding danger and the probability of undesired events
arising. The risk graph gives information on the quality level in the case of protection facilities for
measurement, open-loop control and closed-loop control.
DIN V 19250 classifies systems according to 8 quality levels. The quality levels of individual
protection functions can be determined by means of a risk graph.
Each combination of risk parameters results in a "risk evaluation package". The different gradings
permit a total of 48 combinations.
Figure 1-1. Risk Graph and Quality Levels
G2
G1
A1
A2
A2
A1
S1
S3
S2
S4
2
3
4
5
6
7
8
W3
1
2
3
4
5
6
7
W2
-
1
2
3
4
5
6
W1
Quality levels
G2
G1
-
-
1
Risk Parameters
•
Extent of damage
S1: Minor injury
S2: Major irreversible injury of several persons or death
S3: Death of several persons
S4: Catastrophic effects, large number of deaths
•
Duration of stay in hazardous area
A1: Seldom to occasionally
A2: Frequently to permanently
1-2
EWA 4NEB 812 6210-02