Product Description:

The 7226AC DC servo amplifier is produced by Copley Controls as a member of the DC Servo Amplifiers series. Designed for closed-loop motion systems, it translates velocity or torque commands into controlled armature current so that industrial actuators follow position, speed, or tension profiles with minimal error. By managing both the polarity and magnitude of the motor supply, the module forms the link between low-power control electronics and the electromechanical axis in packaging lines, pick-and-place gantries, and similar automation equipment.

The power stage delivers a continuous output of 10 A and can generate up to 20 A for short accelerations. It maintains a nominal bus voltage of 130 V, while transient commands are limited to a peak of 110 V at the motor terminals. Pulse-width modulation is executed at 25 kHz, keeping current ripple low and moving switching noise above the audible range. An enable command is processed in 1 ms, and the drive accepts reference signals through a 94 kΩ differential input that tracks logic levels above the 2.5 V threshold. Thermal and conduction losses are reduced by an on-resistance of 0.2 Ω, and the design supports motors with at least 400 µH of inductance. The input requires a 16 A supply, and inrush current can momentarily reach 37 A during capacitor charging.

Servo loop performance is supported by a small-signal bandwidth of 3 kHz, allowing the amplifier to reproduce rapid command changes without instability. Protective circuitry disconnects the power stage if the case temperature rises to 70 °C. The stage also disconnects if the bus voltage exceeds 195 VDC or falls below 45 VDC. These limits protect the amplifier from ambient overheating, regenerative surges, and brownout conditions that could saturate the output devices. Additional safeguards prevent shoot-through during startup and automatically shut down the amplifier when logic power is lost.