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DC Motor-speed Sensor

CDA Systems' CMSS56 DC motor speed module measures the speed of a commutated/ brushless DC electric motor based on the ripple in the motor's supply current. No physical contact or line of sight is required.

This device allows accurate testing of motor speed where the rotating parts of the motor are not accessible. These include automotive products such as electric fuel pumps and electric water pumps. However, the product was intended to address a wider range of applications where previously tested motors are embedded inside of another product, such as an automotive HVAC unit, a power-seat motor, or even a cordless power-tool.

CDA's modules re-calculate the motor speed on every single commutation of the motor under test, based on the time required for one complete rotation of the motor. This allows accurate speed tracking during acceleration, allowing accurate motor performance measurements to be made. The real-time response of the CMSS56 unit also makes it an ideal source of feedback for systems requiring motor speed control. Custom variations available on request.

Contact:

Emmet Raftery,

CDA Systems Ltd.

481 Baker St.

London, Ontario

Canada, N6C 1Y1

Tel.: (519) 438-2280

E-mail: eraftery@cdasys.com