Tronic Thermal Overload Relay 55-70Amps

Our review

This is a thermal overload relay from Tronic with a setting range of 55 to 70 amps. Its job is straightforward: it watches the current flowing to a motor and trips the circuit when that current stays too high, which is what causes windings to overheat and fail. It suits electricians, workshop owners, and maintenance teams working on motors and driven equipment in that current band, rather than anyone protecting small domestic appliances.
Before buying, confirm the full-load current of the motor you are protecting falls inside the 55-70A window, since a relay set outside its range will either nuisance-trip or fail to protect. Check the trip class your application needs and whether the relay must match a specific contactor series, because thermal overloads are usually mounted directly onto one. Also confirm the auxiliary contact arrangement suits your control circuit.
Compared with electronic overload relays, a thermal unit like this is simpler and generally cheaper, but it offers less adjustability and no digital readout. If your motor runs at a steady load, that trade-off is usually fine. If loads vary widely or you need precise settings, an electronic relay may serve you better. The unit is available on Sokonia.