Part number 25-ENC-1 by Allen Bradley is an incremental quadrature encoder. This encoder is designed to work with PowerFlex 525 variable frequency AC drives. This encoder may be powered by 5 or 12 volts, accepts 5, 12, or 24 volts, and has a single-ended or differential input wire layout. The 25-ENC-1 is utilized to provide closed-loop PM control using PowerFlex 525's closed-loop velocity vector controlling approach. This provides extra positioning control capabilities in addition to the conventional frequency control that influences the speed of rotation of the attached motor. This PowerFlex 525 device may additionally direct the positioning of the motor using position control.

In addition to being powered externally, this encoder can be driven internally by the PowerFlex 525 drive. This encoder requires a nominal supply voltage of 12 volts DC while actively using 250 mA when operated internally. This device has an inbuilt DIP switch for selecting the voltage source. The maximum acceptable wire size for the terminal signals and power connections to the incremental encoder's built-in terminal is 2.08 mm², while the lowest wire size is 0.08 mm². It is recommended to tighten each terminal with 0.18 to 0.22 Nm (1.56 to 1.9 lb-in) of torque.

To attach the 25-ENC-1, turn off the power to the drive. Use a suitable lock-out method to protect the drive from being powered up while fitting this module. In addition, wait three minutes before beginning the module installation. Allow the capacitors to drain to a safe voltage level. Locate and remove the PowerFlex 525 drive's control module rear cover. Set the encoder's voltage DIP switch to specify a voltage source, either outside or internally. Align the encoder module with the locking tab and snap it to the controlling module rear cover.