DRO 300

Programmable digital readout for 3 or 4 axes

The ACU-RITE DRO 300 is a versatile digital readout designed primarily for milling, drilling, boring, and lathe machines with up to four axes. A separate I/O unit provides switching input/outputs for simple tasks in automation.

Thanks to its splash-proof full-travel keyboard, the DRO 300 is exceptionally well-suited for use in a workshop. It supports all operations with intuitive interactive menus on its large, easy-to-read colour flat-panel display.

The DRO 300 has the same functions as the DRO 203.

In addition, the DRO 300 offers a connection for the KT 130 edge finder. This allows you to define presets and datums with speed and precision. The DRO 300 digital readout supports you with special probing functions.

In addition, the DRO 300 is programmable, which makes it ideal for small-batch production on conventional machine tools. The DRO 300 allows you to store up to eight programs, each with up to 250 working steps. Programs are created by either keying them in step by step or by generating them using actual position capture (teach-in programming).

Data Interfaces
A USB port enables the writing and reading out of data and files.


Axes 3 or 4; various axis designations
Encoder inputs TTL
Display step1) Adjustable, max. 7 digits
Linear axis: 1 mm to 0.0001 mm
Angular axis: 1° to 0.001° (00° 00′ 01”)
Display 7″ TFT color screen (15:9); resolution 800 x 400 pixels for position values and dialog
Status display TTool, reference point, operating function, feed rate, ABS/INC, mm/inch, stopwatch
Axis display Switchable between DRO1 and DRO2
  • 10 reference points
  • 99 tools
  • REF reference-mark evaluation for distance-coded or single reference marks
  • Distance-to-go mode
  • Scaling factor
  • mm/inch switching
  • Absolute-incremental display
  • Integrated help function
  • Graphic positioning aid (“near zero” warning)
  • Calculator
For milling/drilling/boring
  • Calculation of positions for hole patterns (bolt circles, linear hole patterns)
  • Tool radius and tool length compensation
  • Probing functions for reference-point acquisition with KT edge finder: “Edge,” “Centerline” and “Circle centre”
  • Oblique line, circular arc
  • Linear hole patterns, bolt hole circles
For turning
  • Taper calculator
  • Radius/diameter switching
  • Freezing the tool position for back-off
  • Vectoring: X/Y display of the traverse path with inclined top slide
  • Sum display for Z and ZO (axis coupling)
Programming 8 programs with up to 250 steps
Error compensation
  • Axis error: Linear and multipoint over up to 200 points
  • Backlash compensation: for compensation of reversal error
Data interface USB connection, Type C
Switching I/O
  • Input for edge finder
  • Further inputs/outputs over the IOB 610 external input/output unit
Accessories Stand, holder for mounting arm, protective cover, KT 130 edge finder (for milling)
Power connection AC 100 V (–10 %) to 240 V (+5 %), 50 Hz to 60 Hz (±5 %), 33 W
Operating temperature 0 °C to 45 °C (storage temperature –20 °C to 70 °C)
EN 60 529 IP 40; front panel IP 54
1.7 kg
  1) Depends on the signal period of the connected encoder


Please note that only the products that are listed on this website are available for purchase in the United Kingdom.