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Supplementary data
Operating Manual PNOZ s30
1001715-EN-15
81
9
Supplementary data
9.1
Service life graph of output relays
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.
Example
}
Inductive load: 0.2 A
}
Utilisation category: AC15
}
Contact service life: 1 000 000 cycles
Provided the application to be implemented requires fewer than 1 000 000 cycles, the PFH
) can be used in the calculation.
To increase the service life, sufficient spark suppression must be provided on all relay con-
tacts. With capacitive loads, any power surges that occur must be noted. With DC contact-
ors, use flywheel diodes for spark suppression.