Product Description:

The SC402-048-T4 servo drive is produced by Pacific Scientific as part of the SC400 Servo Drives series. Designed for permanent-magnet brushless motors, the unit converts fixed AC mains into a regulated DC bus and pulse-width-modulated output phases for closed-loop speed and torque control in automated machinery. It accepts velocity or torque references from external analog or digital controllers, allowing straightforward integration into existing control cabinets. This arrangement supports stable motor control during speed changes and varying load conditions without requiring a separate external power conversion stage.

With a 115 VAC line supply, the internal DC bus stabilizes at 160 VDC, while a 230 VAC line raises the bus to 320 VDC. These bus levels set the voltage available to the motor windings during operation. The command input has a high input impedance of 50 kΩ, so analog controllers can provide the reference signal without excessive loading. A continuous output capability of 3.5 A supports steady-state motion, and the current loop bandwidth reaches 3 kHz for rapid response to load disturbances. Pulse switching occurs at an output ripple frequency of 20 kHz, which places the switching noise above the audible range and helps reduce audible motor noise.

For dynamic moves, the amplifier can deliver a peak current of 7.0 A and up to 2000 W when powered from 230 VAC, allowing short bursts of acceleration without thermal trip. The front-panel monitor provides a full-scale reading of 4.4 VDC, and the scale factor of 0.63 V/A allows the measured test-point voltage to be converted directly into actual phase current. A sink capability of 25 mA and a maximum fault output of 30 VDC provide a clear hardware status signal for connected PLC inputs when protection thresholds are exceeded. The tachometer gradient of 4.0 V/Krpm matches standard DC tachs, so velocity feedback can be wired without additional scaling components.