Contact Protection or Arc Suppression is required when a reed contact is being used to switch an Inductive Load or a Capacitive Load where surge current or in-rush current is present. Additional components like resistors or capacitors may need to be added for protection from in-rush weld, chatter or Back EMF. Not using recommended methods for contact protection will lead to early failure of the Reed Contact.
Contact protection methods are designed to mitigate the wear and degradation occurring during the normal use of contacts within an electromechanical switch, relay or contactor and thus avoid an excessive increase in contact resistance or switch failure.