Connecting DRO Scales to TouchDRO

Start here if you're wiring DRO scales to TouchDRO (or trying to figure out what you have). The two things that matter are your scale's signal type and its pinout.

A quick heads-up: the connector shape (DB9 "monitor plug", round 5-pin, phone-style, etc.), the brand on the sticker, and the scale's external appearance are not reliable indicators of compatibility. Identical-looking scales can use completely different electrical outputs.

If all you know is the connector type or the wire count, don't worry — start with Scale Signal Types. Once you identify the signal family, choosing the right TouchDRO adapter and wiring method becomes straightforward.

Which situation are you in?

You're shopping for new scales (or just bought them new)

You should expect the manufacturer or seller to provide a datasheet with the output type and wiring/pinout. If you can't find documentation before buying, treat that as a red flag and consider a different supplier. Once you have the datasheet, identify the signal family and confirm it is supported by TouchDRO.

You have an older legacy DRO setup and documentation is missing

First, check our Pinout Library. If it's not there, try searching by model number and connector type (many legacy pinouts are archived online). If the original DRO display still works, probing the DRO's scale input connector is often the fastest way to identify signals (for example: supply pins, A/B/Z pairs, RS-422 pairs, etc.). If you still can't find reliable info, use the reverse-engineering guide as a safe last resort.

You have newer brand-name scales (Newall, Acu-Rite, Mitutoyo, etc.)

Many major brands have excellent support and can provide pinout documentation if you give them the exact model number (and sometimes the cable part number). If we don't already have it in the Pinout Library, manufacturer support is often the fastest path to a correct answer.

You have unknown/no-name scales (import, surplus, or re-branded)

Assume the connector, wire colors, and branding may be unreliable. Start by identifying the signal family, then use the reverse-engineering guide to safely identify power and signal pins before connecting to any equipment.

Step 1: Identify the Signal Family

If you're not sure what your scales are, start here. Once you identify the signal family, choosing the right TouchDRO adapter and wiring method becomes straightforward.

Step 2: Find the Pinout (or Verify It)

Once you know the signal family, find the pinout for your specific scale/cable. If you can't find reliable documentation, verify it before applying power.

Common families

If you're stuck identifying the pinout

If you still can't find a reliable pinout after checking the library and the reverse-engineering guide, you can contact us. To avoid a long back-and-forth, please include as much detail as you can up front:

Our contact form does not support file uploads, but photos are often the quickest way to identify a scale. If needed, we'll reply and ask you to send photos of the connector, scale label, and any wiring diagram that came with it.

Step 3: Connect and Configure

  1. Confirm your scale is supported: Supported DRO Scales
  2. Wire the hardware: Hardware Setup
  3. Finish setup in the app: Initial Configuration