The poles of the type N contactors (namely the antiarc devices, pressure springs, shape of contacts, the movement's dynamics and arc chutes) have been carefully designed so that the following features are achieved :
– Very low contact bounce;
– Relative brushing of the contact's surfaces with the resulting self-cleaning effect;
– Low probability of arc re-priming, even with current, voltage and inductance perticulary high;
– Regular wear of the contacts.

The poles of the type N contactors are normally fitted with very hard copper contacts and the application of sintered contacts is not needed. However, depending upon the application, the following types of contacts are recommended:
- Cooper contacts: for every purpose with breaking current up to 6-8 times lth and voltage up to 600V;
- Sintered contacts in silver-cadmium oxide: for general purpose. Suitable where low and constant contact resistance is required (Type S1).
- Sintered contacts in silver-tungstan : for an extremely high number of operations or for voltages above 600V and with high breaking current, where a low contact resistance is not needed. (Type S4).

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