There are different ways to classify relays. The following groupings will be used in this technical guide.
Types of Relays
Types of Electromagnets
Relays are classified into the following types, depending on whether or not they have a permanent magnet.
Non-polarized relays do not use a permanent magnet in their electromagnetic section. This means that generally the operating coils do not have polarity.
There are some non-polarized relays, such as those with built-in operation indicators or surge-absorbing diodes, whose operating coils have polarity.
Polarized relays use the magnetic flux of the permanent magnet in their electromagnetic sections. This means that the operating coil has polarity.