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Entry type: FAQ, Entry ID: 109758261, Entry date: 09/21/2018
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What is the difference between positively driven contact elements of contactor relays and mirror contacts of power contactors?

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This article contains a statement on the difference between the terms mirror contact and positively driven contact.

QUESTION:

What is the difference between positively driven contact elements of contactor relays and mirror contacts of power contactors? What is the impact for the application?

 

 

ANSWER:

In the IEC 60947-5-1 the term "positively driven contact" is defined in detail in Annex L. Also a corresponding symbol was specified and tests for the verification of "positively driven contactor relay contacts" are described. These characteristics of positively driven operation only referred to the contacts in the contactor relay.
For the contact characteristics of power contactors, the IEC 60947-4-1 standard defines the term "mirror contact" for power contactors. In addition, a symbol for such mirror contacts as well as tests for the verification of the mirror contact characteristics are specified.

The facts are described in detail in the following   Positivelydriven_mirror_contact_V2_0_en.pdf (785,7 KB).

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