WIKA GDM-100-TA Operating Instructions Manual page 15

5. Commissioning, operation
5.2.2 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 we recommend one of the following protective circuits:
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.
Example:
Contact protection
measure with free-
wheeling diode
Inductive load with AC voltage
With AC voltage two protection measures are possible:
Example:
Contact protection
measure with
voltage-dependent
resistor VDR
Example:
Contact protection
measure with RC
element
WIKA operating instructions, models GDM-100-TI, GDM-100-TA
Contact
Diode Load
Load
Load
EN
15