RTA Open-Frame GMD 03 Stepping Motor Drive

The GMD 03 is a high-performance, open-frame stepping-motor drive from R.T.A., designed for controlling two-phase stepper motors in demanding industrial and multi-axis automation systems. Even though this model is now offered only as a spare part (no longer in active production), it remains a reliable solution — widely used in legacy systems and motor-control racks requiring backward compatibility. RTA Store+1

✅ Key Features & Benefits

• Robust Power Range: Operates from 55–85 VDC and drives motors within 4.0 to 10.0 A per phase — suitable for mid-to-high power stepper motors. RTA+1

• Step-and-Direction Interface: Easy to integrate with common motion controllers and legacy control systems. RTA+1

• Microstepping Support: Configurable microstepping with 200, 400 or 800 steps / revolution via DIP-switches — enabling smoother motion and finer positioning compared to full-step drives. RTA

• Automatic Standstill Current Reduction: Reduces motor current when idle — helps minimize heat, power consumption, and wear during hold phases. RTA

• Motor-Current On/Off Control: Allows motor power to be turned off by an external logic signal, useful for multi-axis systems where some axes may idle. RTA+1

• Built-in Protections: Includes under-voltage, over-voltage, short-circuit (on motor outputs) and over-heat protection — safeguarding both the drive card and connected motors. RTA

• Electronic Damping (Resonance Suppression): Dual-circuit electronic damping reduces acoustic noise and mechanical vibrations at low and medium speeds — important for precision and quieter operation. RTA+1

• Compact Open-Frame Form Factor: Eurocard-style board (≈ 100 mm × 160 mm × 45 mm) designed to be mounted into a drive rack, making it suitable for multi-axis or complex automation setups. RTA+1

📊 Technical Specifications (Summary)

⚠️ Notice (Spare-Part Status)

• This model is offered only as spare part — it is no longer in production for new projects. RTA Store

• The supply does not include wiring cables — you must supply appropriate cables/connectors based on your system. RTA Store

• Because it’s spare-part stock, delivery times may vary compared to standard new-product orders. RTA Store

🏭 Typical Applications

• Replacement or maintenance of existing systems built around GMD-series drives.

• Multi-axis CNC machines, automation cells, or robotic platforms where step-and-direction control and microstepping are used.

• Retrofitting or refurbishing industrial motion-control racks where backward-compatibility with older systems is required.

• Applications demanding reliable, high-current stepper drive capability with fine microstepping and current control.