Brushless Operation
Rotor motion is started by generating a revolving magnetic field in the stator windings which interacts with permanent magnet fields in the rotor. The revolving field is created by sequentially energizing the winding phase pairs. The winding phase pairs are energized with current flow in a set sequence to produce the desired direction of rotation. At any instant, two of the three phases are energized while the third phase is off. Energizing two phases simultaneously combines the torque output of both phases and increases overall torque output. The Model 3912 Encased Control has a pre-wired single cable terminated (figure 1). This simplifies all commutation and power connections to stock motors and gearmotors. Chassis style controls and low voltage controls require separate connections for power leads, commutation, and (if provided) encoder leads. Motor power leads are equipped with quick disconnect terminals or terminal blocks for easy control board connection. The commutation leads from motor and extension cables are terminated with a six-pin, 0.1" center in-line connector which plugs into the commutation terminals on many Bodine control boards. See figure 2. Stock motors and gearmotors for use with 115 VAC input controls have a circular connector containing phase leads and commutation connections. The connector on the motor is AMP No. 206044-1, with No. 66098-7 pins and No. 206070-1 strain relief. The mating connector is AMP No. 206043-3 with No. 66100-7 pins (see figure 1 ). The Motor To Control Connections table shows a cross reference of lead color code, rectangular commutation connector, and circular connector pin numbers. Commutation Sequence: The output truth table for the Hall sensor devices and the corresponding driver outputs which must be switched +on+ to create phase current flow sequences is shown below. This sequence causes a Bodine brushless motor/gearmotor to rotate clockwise. The output shafts of gearmotors with odd number of stages (Bodine Type designation ending in -D3, -Z3, -W3, -E1, or -E3) will rotate in the opposite direction. The rotational direction can be changed to counterclockwise by reversing the phase current flow sequences (6, 5, 4, 3, 2,1). The output truth table for the Hall sensor devices and the corresponding phase current output switch must be switched on to create counterclockwise rotation is shown in the motor rotation table.

Brushless Advantages
Brushless motors provide less maintenance, long life, low EMI, and quiet operation. They produce more output power per frame size than PM or shunt wound motors and gearmotors. Low rotor inertia improves acceleration and deceleration times while shortening operating cycles and their linear speed/torque characteristics produce predictable speed regulation. With brushless motors, brush inspection is eliminated making them ideal for limited access areas and applications where servicing is difficult. Low voltage models are ideal for battery operation, portable equipment, or medical applications where shock hazards cannot be tolerated .