255-CZS72-080 — 6 kW 72V PMSM motor

15.9 Nm continuous at 3,600 RPM · 45.5 Nm peak · 255 frame

The 255-CZS72-080 is a 6 kW 72 volt BLDC motor built for speed rather than pulling force. It holds 15.9 Nm continuously at 3,600 RPM on 80 Arms, and will take 45.5 Nm in short bursts at 240 Arms — nearly three times its continuous torque, from a frame weighing 23 kg.

Eighty amps is a small number for six kilowatts, and that is the point of this winding. On a 72 volt bus the motor reaches 6 kW without the heavy cable, the oversized contactors or the high-current controller that the same output would demand at 24 or 48 volts. For equipment where the electrical installation is the expensive part rather than the motor, working at 72 volts and 80 amps is what makes the package affordable. At 23 kg it is also the lightest machine in the 255 frame, which matters where the motor has to be carried, hung off a bracket or mounted high.

The trade is drive frequency. At 3,600 RPM on a ten-pole rotor the controller sees 300 Hz, which is at the upper end of what many general-purpose BLDC controllers will commutate cleanly. Check that figure against a candidate controller before specifying — one that cannot follow it will either derate or run rough. In exchange the rotor inertia is only 0.004057 kg·m², the lightest of any 255 winding, so the machine accelerates and reverses quickly and does not punish duty that starts and stops often.

It is the fast end of a three-winding family that holds roughly the same torque and uses current to buy speed: the 255-CZS72-028 gives 13.8 Nm at 1,400 RPM on 28 amps, the -050 gives 14.7 Nm at 2,400 RPM on 50, and this one gives 15.9 Nm at 3,600 RPM on 80. Choosing between them is a speed decision, not a torque decision.