Product Overview

The Allen-Bradley 1398-DDM-005​ is a 500 Watt universal digital servo drive from Rockwell Automation’s ULTRA 100 Series, designed to close the current, velocity and position loops around a brushless AC servo motor entirely in software. Part of the 1398 ULTRA family that Rockwell inherited from the Electro-Craft IQ line, the Allen-Bradley 1398-DDM-005​ packs the power stage, integral power supply, digital signal processing and all connectors into a single compact “book-style” enclosure, and it draws its mains supply directly from a 100 to 240 V AC single-phase line at 47 to 63 Hz — no external transformer required. That universal input means one drive part number covers both 120 V and 240 V installations anywhere in the world, which is why it became a favourite of machine builders exporting equipment.In ratings terms, the Allen-Bradley 1398-DDM-005​ delivers 2.5 A continuous output current with 7.5 A peak, giving roughly 0.3 kW at 120 V AC and 0.6 kW at 240 V AC of continuous power, with peak output reaching 1.8 kW at 240 V AC. Control performance is where the digital architecture shows: a 125 microsecond current loop, velocity loop bandwidth up to 300 Hz and a 1 ms position loop, all implemented on a microcontroller, with sinusoidal commutation driven from a single motor-mounted encoder.Flexibility is the other defining trait. The Allen-Bradley 1398-DDM-005​ accepts ±10 V analogue velocity or torque commands, eight binary presets, step and direction or CW/CCW pulse trains up to 1 MHz, master encoder following for electronic gearing, and serial host commands over RS-232 or RS-485. Combined with IPM output stage protection, a bi-colour status LED and an EEPROM personality module that stores motor and application parameters, it is a genuine single-axis motion controller in a very small package.

Technical Specifications

Main Features and Advantages

Universal input, one part number worldwide: The Allen-Bradley 1398-DDM-005​ accepts anything from 88 to 265 V AC at 50 or 60 Hz on a single-phase supply, so the same unit covers 120 V North American machines and 230 V European or Asian installations. For OEMs shipping identical equipment to different markets, that removes a variant from the bill of materials and simplifies the spare-parts list for the end user.Fully digital loops with no adjustment drift: All current, velocity and position control, plus motor commutation, is performed by microcontroller, and every parameter is set in software. Unlike an analogue drive with trimming potentiometers, the Allen-Bradley 1398-DDM-005​ cannot drift out of tune with age or temperature, and settings can be uploaded, backed up to a PC and restored to a replacement drive in minutes — a significant advantage when a failure occurs and the original commissioning engineer has long since moved on.Command flexibility that replaces a stepper system: Because the drive accepts step and direction, CW/CCW, master encoder following and eight preset selections at up to 1 MHz, the Allen-Bradley 1398-DDM-005​ can be dropped into architectures that would otherwise require a stepper drive or a separate motion controller, while delivering genuine closed-loop servo performance and full torque at zero speed.IPM output stage with layered protection: Intelligent Power Module technology generates the high-frequency PWM sine wave that drives the current loop, and it brings over-current, short-circuit and over-temperature protection with it. Add bus over-voltage and under-voltage supervision, a bi-colour status LED and dedicated READY and BRAKE relay outputs that can drive a motor holding brake directly, and the Allen-Bradley 1398-DDM-005​ covers the interlocking duties that would otherwise need external relays.Compact footprint with personality module convenience: At just 1.68 kg in a narrow book-style housing, a multi-axis panel can be laid out tightly. The EEPROM personality module stores motor and application parameters, so a motor change or a drive swap becomes a predictable task rather than a re-tuning exercise.