Product Description:

The S7720C-DNF2-PM is a servo drive produced by Kollmorgen and belongs to the S700 Servo Drives series. As a closed-loop amplifier, it delivers regulated three-phase power to synchronous or asynchronous servomotors used in positioning, packaging, and general automation machinery. It is intended for axes that require accurate speed regulation and repeatable positioning under changing load conditions.

The drive accepts mains from 208 to 480 V and draws up to 50 kVA of input power under full dynamic load. Its continuous phase output is rated at 72 A rms, while acceleration and deceleration events are supported by a peak capacity of 140 A rms. A form factor of 1.01 keeps motor current nearly sinusoidal, and the residual voltage drop across the power stage is limited to 6 V for efficient power delivery. Safe Torque Off is implemented as dual-channel STO, allowing category-compliant shutdown without external contactors. Logic and feedback wiring use a Posi/O signal level of 5 V. The disabled stage loss of 24 W represents standby heat dissipated when the output is inhibited. The drive uses coldplate construction, so mounting the base to a liquid-cooled panel removes switching heat. An expansion card slot is populated with a fan controller that activates cabinet airflow at 65 °C ambient or when the heat sink reaches 80 °C.

The internal braking circuit connects to a 10 ohm resistor and can absorb 8 kW continuously to manage regenerative energy during frequent stops. For short pulses at 480 V, it tolerates up to 70 kW, preventing DC bus rise above the overvoltage trip of 900 V. Output current quality is maintained by the 1.01 form factor, and stage switching leaves only a 6 V drop, which helps motor efficiency during high-duty cycles. Because the coldplate removes most heat directly, the temperature-controlled fans operate mainly when ambient or heat-sink thresholds are exceeded.