Product Description:

The CTM21NLS19NAA00 is a two-phase hybrid stepper motor in the CT Stepper Motors series from Kollmorgen. Within an automated machine, this motor indexes a load through discrete angular steps, allowing a PLC or micro-step drive to position tooling or conveyor sections without feedback devices. The Cool Torque Maximum design raises torque density while keeping thermal rise low, so motion axes can fit into compact spaces and still provide repeatable incremental motion.

The motor body follows the NEMA through-hole mounting layout and has a frame envelope of Size 23 / 5.7 cm. Each electrical step equals 1.8°, resulting in 200 full steps per revolution, and this geometric division simplifies open-loop control algorithms. Driving current is limited to 1.9 A per phase, a value that matches mid-range micro-stepping drives and keeps copper losses within safe limits. Coil copper presents a resistance of 2.44 Ω, so the drive must source sufficient voltage to reach rated current quickly. The inductive component of each phase is 3.7 mH, which affects the electrical time constant and influences the highest step rate that can be commanded without torque roll-off. Six pre-tinned lead wires provide flexible connection to bipolar or unipolar drive topologies, and insulation is rated for 340 VDC with 100 MΩ resistance to ground.

An axial thrust limit of 50 lbs in either direction allows the round smooth shaft to carry moderate belt tensions, while the radial rating of 20 lbs at the shaft center supports side-loaded pulleys. Low rotor inertia of 0.0035 oz-in-s² enables rapid acceleration between step commands and reduces settling time, which is important when the ±3% step accuracy must be met in high-speed indexers. The single-stack construction, combined with a thermal resistance of 3.57 °C/W, confines heat to the motor frame so that the overall unit weight stays at 1.5 lb, easing gantry or pick-and-place payload calculations.