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WIKA operating instructions, model GDM-RC-100
EN
14385258.01 04/2020 EN/DE
5.2.7 Contact protection measures
Mechanical contacts must not exceed the specified electrical values for switching
current, switching voltage and switching power independent of each other, not even for
a short time only.
For capacitive or inductive loads one of the following protective circuits is
recommended:
Inductive load with DC voltage
With DC voltage the contact protection can be achieved via a free-wheeling diode,
connected in parallel to the load. The polarity of the diode must be arranged so that it
closes when the operating voltage is on.
Inductive load with AC voltage
With AC voltage two protection measures are possible:
Example:
Contact protection
measure with free-
wheeling diode
Contact
Diode
Load
Example:
Contact protection
measure with voltage-
dependent resistor VDR
Example:
Contact protection
measure with RC element
Load
Load
5. Commissioning, operation
