Technical details
Operating Manual PSSu E F 2DOR 8(-T)(-R)
21334-EN-13
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INFORMATION
A safety function's SIL/PL values are
not
identical to the SIL/PL values of
the units that are used and may be different. We recommend that you use
the PAScal software tool to calculate the safety function's SIL/PL values.
CAUTION!
It is essential to consider the relay's service life graphs. The relay outputs'
safety-related characteristic data is only valid if the values in the service life
graphs are met.
The PFH value depends on the switch frequency and the load of the relay output.
If the service life graphs are not accessible, the stated PFH value can be used irrespective
of the switch frequency and the load, as the PFH value already considers the relay's B10d
value as well as the failure rates of the other components.
8.2
Service life graphs
The service life graphs indicate the number of cycles from which failures due to wear must
be expected. The wear is mainly caused by the electrical load; the mechanical load is negli-
gible.
Number of cycles x 1000
Switching current (A)
Fig.: Service life graph / Switching capability 24 VDC / 250 VAC
