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2-phase drives

Speed and torque performance of the step motor is based on the flow of current from the driver to the motor winding. The factor that inhibits the flow, or limits the time it takes for the current to energize the winding, is known as inductance. The lower the inductance, the faster the current gets to the winding and the better the performance of the motor. To reduce inductance, most types of driver circuits are designed to supply a greater amount of voltage than the motors rated voltage.

• Translators - This type of drive receives low-level signals from another source and converts them into electrical (step) pulses to run the motor. One step pulse is required for every step of the motor shaft. In full step mode, with a standard 200 step motor, 200 step pulses are required to complete one revolution. In microstepping mode the driver may be required to generate 50,000 or more step pulses per revolution.

• Indexer - This type of drive typically operates in a "stand-alone mode" and can operate independent of the host computer. Once downloaded to the non-volatile memory motion programs can be initiated from various types of operator interfaces, such as a keypad or switch, or through the auxiliary I/O inputs. A stand-alone stepper motor control system is often packaged with a driver and/or power supply and optional encoder feedback.

  Both translators and indexers are available as analog or digital drives running in open or closed loop (torque, velocity and position) motor control