Faults - malfunctions, Service life graph – Pilz PNOZ s7 C 4 n/o 1 n/c coated User Manual
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PNOZ s7
Operating Manual PNOZ s7
21399-EN-09
7
Faults - malfunctions
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Contact malfunctions: If the contacts have welded, reactivation will not be possible after
the input circuit has opened.
Service life graph
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: 2,000,000 cycles
Provided the application requires fewer than 2,000,000 cycles, the PFH value (see techni-
cal details) can be used in the calculation.
To increase the service life, sufficient spark suppression must be provided on all output
contacts. With capacitive loads, any power surges that occur must be noted. With contac-
tors, use freewheel diodes for spark suppression.