Product Description:

The S7720A-SEF2-PA is an AC servo drive manufactured by Kollmorgen for the S700 Servo Drives series. It modulates three-phase output to control brushless servomotors used in packaging, printing, and material-handling equipment. Communication with the machine PLC is handled through the built-in SERCOS II fieldbus, while power devices are mounted on a cold plate to aid thermal transfer. Conformally coated circuit boards protect traces and components from moisture and dust, making the unit suitable for installation inside compact electrical enclosures that lack forced airflow. This layout directs heat toward the mounting surface instead of relying only on circulating cabinet air.

The drive accepts a mains supply from 208 to 480 V AC and draws a continuous output current of 72 Arms. Momentary acceleration or shock loads can be covered by a peak capability of 140 Arms. A switching frequency of 8 kHz governs the IGBT pulse pattern so motor current contains low ripple even at high speeds. Total apparent power at the input is rated at 50 kVA, which is used when sizing upstream protective devices and cabling. With a width of 190 mm, a height of 386 mm, and a depth of 244 mm measured without front connectors, the aluminum housing fits on 300 mm deep control panels, and the assembled unit weighs 13 kg.

The mechanical brake interface can absorb up to 8 kW of continuous energy, and Kollmorgen recommends an external resistor of 10 ohms when dynamic stopping demands exceed the internal dissipation limit. Safety integration is simplified by the dual channel STO circuit, which removes drive power without a contactor. Two differential analog inputs and two analog outputs are available for torque trim, speed demand, or diagnostic feedback, and each input is resolved to 1.25 mV for fine signal adjustment. A fan controller expansion card and a controlled fan option regulate enclosure temperature and help reduce thermal stress on internal components.