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Series vs Parallel wiring in motors

A stepper motor may be wired in either series or parallel, depending on the needs of the application. A series-wired motor will deliver more stall torque, but torque drops quickly as velocity increases. A parallel-wired motor typically maintains its (lower-than-series) torque to a higher velocity.

Parallel wiring gives 1/4 the resistance and inductance of series wiring, resulting in more current, and therefore more heat generated. Therefore, we recommend that whenever you wire a motor in parallel, you limit its duty cycle to 50%, and engage Auto-Standby on the drive. This allows the motor to cool off between runs. The motor case temperature must always be kept below 100C. If the motor is rising above 80C, do something to prevent it from reaching 100C: attach a heat sink, lower the duty cycle, lower the current, etc. Heat sinks are usually the best way to effectively cool a motor.