MDrive AccuStep 34ac
- NEMA 34 1.8° brushless stepper motor
- microstepping driver
- 120 or 240 VAC integrated power supply
- internal optical encoder with choice of line counts
- AccuStep control technology's numerous benefits
- RS-422/485 communication
- IP65 rating
- 3 motor length choices
- optional control knob or planetary gearbox
This product has three (3) operating modes, selected and
configured with an easy-to-use GUI:
- Step – microstepping step & direction for point-to-point
positioning - Torque – regulates and maintains a set torque
- Speed – maintains velocity/speed with built-in oscillator
- Specifications
- Options
- Connectivity by P/N
- Downloads/Support
- Applications
- General
- Motion
- Setup parameters GUI
- Motor
- Mechanical
| Input voltage (+V) |
Range | 120 Volt version – 95 to 132 VAC @ 50/60 Hz 240 Volt version – 95 to 264 VAC @ 50/60 Hz |
|
| Communication | Type | RS-422/485 | |
| Baud rate | 4.8 to 115.2 kbps | ||
| Thermal | Operating temperature | Heat sink | -40° to 75°C (non-condensing) |
| Motor | -40° to 90°C (non-condensing) | ||
| Protection | Type | Thermal, internal fuse | Designed for line-neutral systems |
| Isolated input | Voltage range | +5 to +24 VDC sourcing or sinking | |
| Digital filter range | 50 nS to 12.9 µS (10 MHz to 38.8 kHz) | ||
| Clock types (Step mode) |
Step/Direction, Quadrature, Step Up/Step Down | ||
| Step frequency | 5 MHz maximum | ||
| 100 nS minimum pulse width | |||
| Closed loop configuration | Internal magnetic encoder | Resolutions 100, 200, 250, 256, 400, 500, 512, 1000 | |
| Microstep resolution | Number of settings | 20 | |
| Steps per revolution | Binary | 200, 400, 800, 1600, 3200, 6400, 12800, 25600, 51200,
36000 (0.01 deg/µstep), 21600 (1 arc minute/µstep), 25400 (0.001 mm/µstep) |
|
| Decimal | 1000, 2000, 5000, 10000, 20000, 25000, 40000, 50000 | ||
| Operating Modes |
Step & Direction, Torque Control or Speed Control | |
| AccuStep Settings | Setup/ Configuration |
Turn AccuStep off or on in fixed or variable mode; set and confirm encoder line count |
| Operation | Set control bounds for motor torque and speed, lead, lag, and make-up of lost steps | |
| AccuStep Status | Display status alerts of 8 pre-programmed fields, read-only | |
| Calibration | To maintain synchronization, select options for motor's rotor-to-stator physical position | |
| Analog Settings | Set analog ranges, select input mode: 0-5V, 0-10V, -10 to +10V (not applicable for Step mode) | |
| Communication Settings | Set baud rate; enable/disable party mode and features; Check Sum integrity quality assurance |
|
| I/O Settings | Clock and filter settings; Attention Output with 11 pre-programmed fields to select among |
|
| Motion Settings | All operating modes | Set various motion settings, which vary with the operating mode selected ex. Current, MSEL |
| Speed control mode | Additional settings: for setting acceleration, deceleration, velocity and flags | |
| Defaults | Restore system defaults or previously stored settings; view current communication settings | |
| Single length | Double length | Triple length | |
| Holding torque oz-in / N-cm |
330 / 233 | 500 / 353 | 750 / 529 |
| Detent torque oz-in / N-cm |
10.9 / 7.7 | 14.16 / 10.0 | 19.83 / 14.0 |
| Rotor inertia oz-in-sec2 / kg-cm2 |
0.0142 / 1.0 | 0.0227 / 1.6 | 0.0482 / 3.4 |
| Weight (motor+driver) lb / kg |
6.4 / 2.9 | 7.7 / 3.5 | 11.0 / 5.0 |
| Torque/Speed Curve |
|
120VAC motor
|
240VAC motor
|

- QuickStart Kit
- Gearboxes
- Control Knob
- Encoder
- Connectivity Solutions
Planetary gearbox
The MDrive AccuStep 34ac is available with a Planetary Gearbox option developed to increase torque at lower speeds, enable better inertia matching and produce finer positional resolutions. These efficient, low maintenance Planetary Gearbox come fully assembled with the MDrive and are offered in a large number of reduction ratios in 1-, 2- and 3-stage configurations.
| Permitted output torque (oz-in / Nm) |
Gearbox efficiency |
Maximum backlash |
Maximum load (lb-force / N) Output side with ball bearing |
Weight (oz / g) | |||
| Radial | Axial | Gearbox | with Flange | ||||
| 1-stage | 2832 / 20.0 | 0.80 | 1.0° | 90 / 400 | 18/80 | 64.4 / 1827 | 66.7 / 1890 |
| 2-stage | 8496 / 60.0 | 0.75 | 1.5° | 135 / 600 | 27/120 | 89.5 / 2538 | 92.6 / 2625 |
| 3-stage | 16992 / 120.0 | 0.70 | 2.0° | 225 / 1000 | 45/200 | 114.6 / 3248 | 118.5 / 3360 |
See NEMA 34 Planetary Gearbox for ratios and mechanical specifications.
MDrive AccuStep is available with a factory-mounted rear control knob for manual shaft positioning.
Knob shown from rear
Dimensions in Inches (mm)

An internal differential optical encoder with index mark is included with signals made available for external use. Resolutions from 100 to 1000 lines are available. Note: AccuStep control performance is optimized at the higher resolution selections.
Communication Converter
Electrically Isolated, in-line converter pre-wired with mating connector to conveniently set/program parameters for a single MDrive AccuStep via a PC's USB port. Length 12.0' (3.6m).
| Converter Part Number | Mating Connector Type |
| MD-CC401-001 (USB to RS-422/485) | 5-pin M12 circular connector |
Prototype Development Cables
Prototype development cables are designed to speed test/development with pre-wired mating connectors that have flying leads other end. Single-ended cordsets are PVC jacketed with foil shield and unconnected drain wire. Length 13.0' (4.0m).
| Prototype Development Cable P/N | Mating Connector Type | Signal Type |
| MD-CS100-000 (straight termination) MD-CS101-000 (right angle termination) |
19-pin M23 circular connector | I/O |
| MD-CS200-000 (straight termination) MD-CS201-000 (right angle termination) |
3-pin Euro AC circular connector | Power |

p/n: MAM4MRQ34**
Literature
Software
- IMS AccuStep GUI
- Internet installation method - fastest, features automatic updates
- Administrator installation package - requires installation by computer administrator, will install for all users on the PC
- User installation package - installs for a single user on a PC
- Cable drivers
Additional Resources
Benefits
- No tuning required
- Higher inertia mismatch allowed
- High starting torque
- Smooth motion, even at extremely slow speeds
- Eliminates loss of synchronization
- Allows full use of motor’s torque
- Direct access to internal encoder signals
- Reduced motor heating
- Minimizes impact of system resonance
- Can be integrated into existing systems
- Able to regulate torque, even at a standstill
- Variable operating current, only uses the power that is required
Applications
- Point-to-point positioning
– Reduce motor frame size requirement - Conveyor control
– No loss of synchronization
– Adapts to sudden load changes - Hydraulic and pneumatics replacement
– Low cost
– Accurate and variable positioning - Web handling
– Tension control - Drilling
– Variable torque - Rotary and linear positioning to torque specification
– Container capping
– Clamping / holding
– Screw tightening - On-the-fly product marking (labeling)
– High acceleration and deceleration rates




