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On the top row of terminals I have w1, v1, and u1 which I get are connected to v2, u2, and w2 on the second row of terminals. Now, on the bottom row of terminals are two wires labeled 3 and 4. Any idea what they are for and how I should connect them?
It could be a 3 phase, delta-connected motor with thermistor protection against overheating (three series-connected PTC thermistors embedded in the windings and terminated as shown).
The thermistors would enable a thermistor relay at normal temperature and disable the same at a higher temperature.
The thermistor relay, in turn, would enable / disable the motor power contactor.
