Product Description:

The S7720C-NANA-NA is a programmable servo drive from Kollmorgen in the S700 Servo Drives series. It converts three-phase mains energy into precisely regulated, sinusoidal output for brushless servomotors. It also provides feedback processing, fieldbus links, and functional safety features needed to position actuators, gantry axes, and other motion elements in automated machinery.

The drive operates within a line window of 208 to 480 V. Under continuous operation, it delivers 72 Arms of output current, while a surge of 140 Arms can be supplied for acceleration peaks and is permitted for 5 s before the limiter intervenes. Switching devices are gated at 8 kHz, balancing acoustic noise with motor ripple. The power stage accepts 50 kVA from the mains, and motors must present at least 0.61 mH of inductance at 480 V to keep the regulators stable. If the link bus rises above 900 V, an overvoltage trip diverts energy through a 10 Ω external brake resistor. During emergency deceleration, the resistor can absorb 70 kW in pulses, and the coldplate option transfers resulting heat to a user-supplied sink. The unit sheds 24 W when its outputs are disabled, and a dual-channel STO circuit removes motor torque without opening the line contactor. EtherCAT and CANopen interfaces are fitted as standard, so no expansion card is required.

The control side provides one differential ±10 V analog input with 16-bit resolution. It is sampled every 62.5 µs, enabling tight torque loops when a PLC issues velocity or current references. During repetitive stops, the mechanical brake path can dissipate 8 kW continuously, and overall heat loss at 480 V reaches 1135 W when the drive feeds a motor at full load. Both values affect enclosure cooling calculations and should be considered when planning heat removal.