Product Description:

The S7720A-PBF2-PM is a servo drive produced by Kollmorgen for the S700 Servo Drives series. It converts three-phase mains power into regulated motor current so that servomotors can follow position, speed, or torque commands in automated machinery. A pair of 9-pin SubD connectors exposes the PROFIBUS DP fieldbus, allowing the unit to exchange setpoints and diagnostics with a PLC. For machine safety, the drive includes a dual-channel Safe Torque Off circuit that removes power to the motor without mechanical contactors. These functions position the module as a compact controller for axes up to medium power.

Electrically, the drive accepts line voltages from 208 to 480 V and is protected to IP20, so it must be installed inside a cabinet. Continuous output capability reaches 72 Arms, while acceleration and transient events can be supplied with 140 Arms. With a rated input power of 50 kVA, the unit can energize motors that demand substantial dynamic power while maintaining an output-current form factor of 1.01 to preserve sinusoidal motor currents. Switching devices operate at a fixed 8 kHz carrier frequency, and a residual DC bus voltage drop of 6 V supports efficient braking energy return. Position I/O lines use 5 V logic, and a dedicated expansion card governs the heat sink fan.

Thermal supervision is handled automatically: heat sink cooling engages at 80 °C, while the internal electronics fan starts at 65 °C. When kinetic energy must be dissipated, an external resistor of 10 Ω rated for 8 kW can be wired to the regenerative terminals to absorb braking energy during deceleration. Safety circuits benefit from dual-channel STO, which responds in 1 ms on the primary path and 2 ms on the secondary path. Cold-plate construction and coated PCBs add extra protection against condensation and airborne contaminants.