Magnetic relay
A magnetic relay is use to detect high current. It is composed with one coil (which has the load current passing through), a mechanic moving part and contacts. When the current (normal current) is less than the rating, the magnetic flux is too weak to attract the mobile part. If the current is higher than the rating current, the magnetic flux is attracting the mobile part and this one move the contacts. The information given by the contact is used to cut the power. |  |
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 | Single-pole magnetic over current relays, Operating times |
