Product Description:

Pacific Scientific builds the SC724A-001 as part of the SC720 Command Controllers series. Classified in the Servo Controller group, this unit functions as a torque and velocity controller that issues four-quadrant commands for brushless servomotors in automated machinery. By combining resolver feedback with an internal encoder emulator, it closes the loop on position and speed so the drive system can maintain ±22 arcmin accuracy when coordinating multiple axes on a common bus.

The controller is powered from a 240 VAC, three-phase mains supply and internally rectifies this line to a DC bus held at 320 VDC. Under continuous duty it sources 15 A of output current, yet it can deliver 30 A for fast accelerations without saturation. Continuous shaft power reaches 4.5 kW, while the PWM stage, clocked at 20 kHz, keeps current ripple low to protect motor insulation. Bus current draw averages 18 Arms, and the controller can absorb 200 W of regenerative energy through its shunt circuit, or 20 kW momentarily, to help prevent overvoltage trips when loads decelerate. With its four-quadrant topology, the unit supports both motoring and braking in forward or reverse, letting the drive handle closed-loop tension or winding applications that require smooth reversal. Fault conditions are reported to the host PLC through a 3-bit code so diagnostics can be addressed quickly.

Peak mechanical output climbs to 9 kW for brief moves, aided by a resolver-to-digital converter that offers 12-bit resolution and an encoder output of 1024 ppr for legacy position interfaces. The housing measures 16.75 in high, 5.00 in wide, and 10.63 in deep, and the assembly weighs 40 lbs so it mounts inside standard 19-in control enclosures without additional bracing. The unit is part of the 720 series and shares common power rails and status lines with compatible bus modules.