Product Description:

The PC842-001-A is a brushless servo drive produced by Pacific Scientific within the PC800–PCE800 Brushless Servo Drives series. Designed to regulate torque, speed, and position of compatible PM servomotors, the unit forms the power conversion stage between a three-phase 240 Vac supply and the motor phases in automated machinery. By managing current loops and shunt dissipation, it maintains repeatable motion profiles required for pick-and-place cells, packaging axes, and general material-handling equipment. Its control and power functions are intended for machines that need consistent servo response during repeated starts, stops, and speed changes.

During continuous operation, the drive delivers a motor phase current of 2.7 ARMS, which corresponds to a mechanical output of 1.1 kW when fed from a 240 Vac three-phase source. The internal IGBT bridge chops the DC bus at an output ripple frequency of 20 kHz, reducing audible noise and improving current resolution. A 10 A input fuse protects the mains terminals, while the supply line draws 4.5 A under nominal load. Start-up stress is limited by the soft-charge network, but the initial inrush can reach 300 A for 1.0 ms. With a power stage efficiency of 98%, only modest heat sinking is required, and the bus capacitors can absorb 20 J before the shunt begins diverting excess energy at 800 W. This combination of switching control and protective circuitry helps the drive operate smoothly during normal running and bus charging.

For brief acceleration commands, the current loop can supply 5.3 ARMS, allowing the motor to reach a peak mechanical output of 2.25 kW without saturation. Excess regenerative energy is handled by the shunt resistor, which tolerates momentary loads up to 12.8 kW. Motor leads may extend to 50 m without exceeding reflected-wave limits, and the drive accommodates inductances from 4 mH to 4 H for stable control across a broad motor family. That flexibility supports installations where the motor is mounted at some distance from the drive or where winding characteristics vary between axis designs.