Product Description:

The 1MS200H-4B-A2 is an electromagnetic stator assembly produced by Bosch Rexroth Indramat for the 1MB High-Speed Asynchronous Motors series. Installed inside a frameless spindle housing, the unit creates the rotating magnetic field that drives the rotor in machine-tool spindles and other high-speed automation axes. Because the stator is the stationary electromagnetic section of the motor, it supports precise torque generation without requiring a separate external motor housing. Its frameless format also allows the active motor parts to be integrated directly into the spindle structure, which helps reduce radial space.

Electrical termination is handled by a connection cable that is supplied as a 1.5 m loom, and this length supports direct routing to a drive without intermediate junctions. The cable is routed through the stator end, so motor wiring exits on the same side as the coolant ports for a compact machine layout. Heat generated by the windings is removed by liquid cooling, which helps keep winding temperature within acceptable limits during high-duty operation. The stator uses frame size 200, matching the corresponding rotor and bearing sets. Axial stack length is indicated by H as the motor length code, showing the longest active core available in this frame. Surrounding the lamination stack is an aluminum cooling jacket, and its high thermal conductivity transfers heat from the windings into the liquid circuit with minimal temperature difference.

The winding set uses variant 4B, so resistance and inductance are matched to spindle inverters that supply high-frequency current while limiting reactive losses. The jacket’s aluminum mass also stiffens the assembly, which helps keep the air gap stable under centrifugal forces during high-speed operation. The unit serves as a Stator for 1MB Frameless Spindle Motor and can be combined with a separate rotor, sensors, and front-end tooling without changing its integrated cooling or cable routing.