8MSA4M.R0-31 B & R Automation
Wake Industrial LLC is not an authorized distributor of this product.
The B & R Automation 8MSA4M.R0-31 is part of the 8MS Three Phase Synchronous Motors series and features a self-cooling system with a keyed shaft end. This motor has a nominal rated speed of 3000 rpm and uses BRX resolver encoder technology. It is designed with a motor size of 4, medium relative rated torque, and the connection direction on the A side.
Internal Product Review
The 8MSA4M.R0-31 is a B & R Automation 8MS three-phase synchronous motor with self-cooling and a keyed shaft for dependable machine integration. Resolver feedback with ±1 angular minute non-linearity supports accurate motion control, making the motor an excellent choice for precise servo applications.
To contact sales for pricing and lead time:
Payment Methods
Shipping Methods
Our Credentials
Product Description:
The 8MSA4M.R0-31 is a three-phase synchronous servo motor built by B&R Automation for the 8MS Three-Phase Synchronous Motors series. In automated machinery, the motor converts drive output from a digital amplifier into mechanical rotation, allowing axes in packaging, material-handling, or assembly lines to operate with consistent torque and speed. Size code 4 indicates the stator frame and flange geometry, while length code M indicates a medium magnetic stack that balances torque and inertia.
Under nominal excitation, the rotor reaches 3000 rpm, making the motor suitable for direct coupling to a wide range of gearbox ratios. Relative torque is classified as medium, placing it between the light-duty and high-torque options in the series. Heat is removed through self-cooling, so the motor does not require an external blower or coolant circuit. Electrical and feedback cables exit on the A-side, helping with conduit routing while reducing the need to cross moving machine components. The output interface has a keyed shaft end, which provides positive engagement with pulleys, couplings, or gear sets and helps prevent slippage during acceleration. This shaft configuration is appropriate for connections that must transmit torque through a mechanically secured joint rather than relying only on clamping force.
For position feedback, the motor integrates a resolver that uses the proprietary BRX format. Its carrier signal nonlinearity remains within ±1 angular minute, while total accuracy across one mechanical revolution remains within ±10 angular minutes. These tolerances allow the drive controller to close velocity and position loops without requiring additional linearization tables. The motor is supplied without a holding brake, so the drive or an external mechanical device must secure the axis when holding force is required. It is also supplied without an oil seal, making it suitable for installations where the shaft is not exposed to oil, coolant, or similar surface contaminants. Appropriate external protection should be provided if the motor is installed where liquids or debris could reach the unsealed shaft opening.
