Used and surplus encoders for sale. MRO Exchange carries a rotating selection of industrial encoders available for immediate purchase and fast nationwide shipping.
Encoders are position and motion feedback devices that convert mechanical movement into electrical signals a control system can read and act on. In a CNC machine tool, encoders mounted on axis motors and ballscrews provide the continuous position feedback the control needs to maintain precise cutting accuracy. In a servo system, the encoder mounted on the servo motor shaft closes the velocity and position loop between the motor and the drive. Without accurate encoder feedback, precise motion control is not possible.
Incremental vs. absolute encoders:
Incremental encoders generate a pulse train as the shaft rotates, counting pulses from a reference point to determine position. They are the most common encoder type in CNC and servo applications and require a homing routine after power-up to establish a reference position. Absolute encoders output a unique position value for every shaft angle across the full range of travel, retaining position information even after power is removed. Absolute encoders are used in applications where homing after power-up is not practical or where position must be known immediately on startup.
Compatibility considerations for surplus encoders:
Resolution — measured in pulses per revolution for incremental encoders or bits for absolute encoders — must match the requirements of the connected drive or control system. Output signal type, whether TTL, HTL, or serial protocol such as EnDat or BiSS, must be compatible with the receiving device. Shaft diameter, mounting flange, and connector type must match the physical installation. For CNC-specific encoders, cross-reference the exact part number against your machine documentation before purchasing.
MRO Exchange lists manufacturer, model number, and condition for every encoder in our inventory. Every encoder ships nationwide from our facility in Illinois at prices well below new OEM cost. If you do not see your specific model listed, contact us directly as our inventory rotates regularly.
