DRO300 Digital Readout

DRO 300 Digital Readout

The most complete digital readout system in the machine tool marketplace, the DRO300 has full part program capability, 99 tool offsets and multiple DRO displays along with standard input/output capability and edgefinder probe support all on an easy to read 7-inch color display. Designed and manufactured in the USA, ACU-RITE readouts are the first choice of machine tool builders and users alike.

Milling-specific features

  • Bolthole pattern calculations with graphics (full and partial circles/linear patterns)
  • Centerline calculation enables you to establish workpiece zero and midpoints
  • Edge finder input
  • I/O (option)

Turning-specific features

  • Lock axis feature
  • Instant radius/diameter conversion
  • Taper calculator
  • CSS (option)

Dynamic zoom

The currently moving axis can be geographically highlighted. In “dynamic zoom” mode, the position value is zoomed to its maximum size depending on the number of digits. This greatly improves legibility—especially from a great distance. Click here to see Dynamic Zoom in action.

Installation guide

When you switch on the digital readout for the first time, the DRO300 supports you with an installation guide. You are led step by step through the most important settings until the device is ready for operation.

Day/night switching

Depending on the ambient-light conditions at the machine, you can switch the screen of the DRO300 to a light or dark background.

Curious about ROI?

With our DRO ROI calculator, you can input your shop’s characteristics and find out how quickly a DRO can pay you back.

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International documentation

Visit our Manuals & Flyers page and scroll to the bottom for international documentation.

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Frequently Asked Questions

Can the DRO300 be used in EDM machines?

Yes, with an IOB 610 the DRO300 can use six inputs and ten outputs, making them suitable for EDM functionality.

How many axes can the DRO300 work with?

Standard DRO300 readouts work with up to four axes. The IB2X option allows for input of two additional axes, up to six, making the DRO300 readouts a fit for large machine tools.

Can the DRO300 be used with an Edge Finder or touch probe?

Yes, with the help of the IOB 610, DRO300 includes input for touch probes and ACU-RITE Edge Finder with switching signal or contact triggering.


Application Milling, turning, grinding, boring, EDM and general purpose
Axes 2, 3, and 4 from A to Z and Z0
Encoder Inputs TTL
Display Step
  • Adjustable, max. 7 digits
  • Linear axis: 1 mm to 0.0001 mm
  • Angular axis: 1° to 0.001° (00° 00′ 01”)
  • 3 Axes (DRO303) or 4 Axes (DRO304)
  • 7-inch color wide screen (15:9)\
  • Resolution 800 x 480 pixels for Position Values, Dialog Messages, Input and Graphic Functions
Status Display
  • Tool
  • Reference point
  • Operating function
  • Feed rate
  • mm/inch
  • Stopwatch
Axis Display Standard
Common Functions
  • Multiple Display Views – DRO1, DRO2 & DRO3
  • Program Storage
  • Advanced Skew Compensation
  • Job Clock / Stop Watch
  • Feed Rate Display
  • Multiple Language Support
  • Absolute/Incremental
  • Near-Zero Warning with Graphics
  • Help function
  • 99 Tool Offsets/Diameter
  • Preset and Zero Reset
  • 4 Function Calculator/Trig Calculator
  • Instant Inch/mm Conversion
  • Position-Trac™ Home Reference System
  • Linear/non-linear compensation up to ±9,999 ppm
Turning Specific Functions
  • Lock Axis Feature establish tool offsets with the tool under load, resulting in reduced tool deflection
  • Instant radius / diameter conversion
  • Taper calculator, Vectoring
  • INCLUDES Thread Assist simplify cutting metric threads on lathes with English leadscrews
Milling Specific Functions
  • Bolt-hole Pattern Calculations with Graphics (full and partial circles/linear patterns)
  • Centerline Calculation establish workpiece zero and midpoints
  • Edge finder/touch probe input
Cycles Oblique line, circular arcs; only for milling, drilling, boring:circular and linear hole patterns
Error Compensation
  • Axis error: Linear and nonlinear over up to 200 points
  • Backlash compensation: for compensation of reversal error
Data Interface USB 2.0 type C
  • For Output of Parameters to a USB Stick or PC
  • For Input of Parameters, Remote Control of Keys and Commands
Switching I/O
  • Input for Edge Finder (with switching signal or contact triggering)
  • Further input/outputs over the IOB 610 external input/output unit
  • CSS (Constant surface speed), I/O (Input/Output)
  • Multiple Scale Coupling Box
  • Electronic Edgefinder
  • Single-Position Tilting Base, Multiposition Holder, Mounting Frame, Protective Cover
  • IB2X (allows input of 2 additional axis)
Electrical Requirements AC 100 V to 240 V (±10 %), 50 Hz to 60 Hz (±5 %), ≤ 33 W
Operating Temperature 0° to 45º C (32º to 113º F)
Protection EN60529 IP 40, Front Panel IP 54
Weight ~1.9 kg