Product Description:

The BTM-055-20 is a miniature servo amplifier produced by Copley Controls within the Bantam M-Axis Controllers series. This single-axis module drives low-voltage brushless or brushed DC motors in space-constrained industrial automation where precise torque and velocity regulation are required. By converting analog command signals into high-frequency pulse-width-modulated outputs, the controller supplies regulated current to the motor phase windings while monitoring voltage and current limits during continuous machine duty. Its 53.3 × 45.7 × 15.2 mm footprint permits distributed mounting on moving axes, minimizing cable length and electromagnetic interference.

It accepts a ±10 V DC differential command that sets the target current, and the input presents 100 kΩ impedance so that signal sources are not loaded. Under continuous conditions, the drive delivers 10 A DC to the motor, which corresponds to 523 W of electrical output power when operating near the top of its voltage range. A closed current loop with a 2.5 kHz bandwidth corrects phase errors rapidly, while a carrier frequency of 33 kHz keeps switching noise above most audible ranges. The power stage exhibits only 0.075 Ω of output resistance, reducing I²R losses, and it can stabilize motors with inductances down to 200 µH. A dedicated +5 V DC, 250 mA DC Hall supply supports commutation sensors, and an undervoltage threshold of +12 V DC disables output below safe levels.

For transient events, the amplifier can source 20 A DC and as much as 1045 W for 1 second, allowing quick acceleration of high-inertia loads before thermal limits are reached. An internal temperature sensor trips at 70 °C, shutting down the power stage until it cools, and the same logic supervises the peak-time counter to prevent consecutive overloads. When paired with a compliant motor, the low output resistance and high pulse frequency translate these short bursts into repeatable mechanical torque without magnetic saturation.