Adapter for Glass and Magnetic Scales

Adapter for Glass and Magnetic Scales

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Advanced four or six axis DRO adapter for RS-422 and TTL glass and magnetic scales with touch probe and tachometer support.

Regular price $299.00 USD
Regular price Sale price $299.00 USD
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TouchDRO TDA-400 and TDA-420 are the latest generation of our scale interface adapters designed for use with the majority of modern optical and magnetic DRO scales. Thanks to the powerful 32-bit dual core processor and state-of-the art software, these adapters offer unparalleled performance and capabilities that can't be found in any other DRO unit on the market. Learn more



Please see TouchDRO Adapter Feature Comparison for more information.


TouchDRO TDA-400 is a four-axis DRO scale adapter, designed to work with most modern optical and magnetic DRO scales.

  • Up to four 5V RS-422 (differential) or TTL (single ended) DRO scales or rotary encoders (NPN, PNP, and Push-Pull) with reference track support.
  • Bluetooth and USB connectivity (can be used simultaneously)
  • Position retention during power loss
  • Access to TouchDRO Plus application
  • Support for over-the-air firmware update


TouchDRO TDA-420 is an upgraded version of TDA-400 adapter. It includes all of the features listed above, and adds two additional flexible input lines that can be used for a combination of the following:

  • Two additional TTL scale inputs for single-ended optical and magnetic scales, or NPN rotary encoders.
  • Two touch probe/tool height setter inputs (uses one input line)
  • Tachometer input
  • Four limit switch inputs (two inputs per line)

Please refer to the TouchDRO Adapter Feature Comparison for more information.


Compatible DRO Scales

The adapters support DRO scales and rotary encoders that output 5V quadrature signal. This includes the vast majority of modern optical, magnetic, and inductive scales. Learn more


Pinout Options

Four main scale inputs on TouchDRO TDA-400 and TDA-420 use female DB-9 (D-Sub 9) connectors preconfigured for one of the following scale peanuts.

Brand 1 2 3 4 5 6 7 8 9
Acu-Rite SENC Scales   A A' B B' OV/Gnd Vcc/5V R R'
Electronica/EMS, PM MagExact +Z Z' Vcc/5V Shield OV/Gnd A A' B' B
Ditron, Sino, Aikron, Easson, Vevor A' 0V B' Shield R'/Z' A +5V B R/Z
Generic Chinese Pinout (ToAuto, etc.)  5V 0V  A  B  

If you intend to use a mix of the above pinouts, choose the "Mixed". Please use the "Order Instructions" field in the shopping cart to tell us the pinout options for each axis.

Note that TTL scales can be used with RS-422 inputs. In such case, the complementary lines will be left unconnected.