Skip navigation

TONiC™ FS incremental encoder system with RTLC20 linear scale


  • Readhead size: 35 x 13.5 x 10 mm
  • Speed up to 10 m/s
  • Detachable analogue (Ti) or dual output (DOP) interface*
  • Certified to:
    ISO 13849 Category 3 PLd
    IEC 61508 SIL2
    IEC 61800-5-2 SIL2


  • Convenient and robust tape scale
  • Carrier-type scale system for easy installation and replacement of scale
  • Super-compact encoder
  • Advanced signal conditioning for improved motion control
  • High dirt immunity
  • Ultra-low Sub-Divisional Error (SDE): typically < ±30 nm
  • Diagnostic kit
Transparent patch for website banners

What is the TONiC FS encoder?

The TONiC FS series is Renishaw's super-compact, non-contact encoder system that offers speeds up to 10 m/s and, when combined with the DOP interface, resolutions down to 1 nm for both linear and rotary applications. TONiC FS systems are quick and simple to install with wide set-up tolerances and calibration at the push of a button. The TONiC FS encoder's dynamic signal processing gives improved signal stability with ultra-low Sub-Divisional Error of typically < ±30 nm to help realise superior motion control performance. Certified to SIL2 and PLd for use in functional safety applications.

* Only the analogue sine and cosine outputs are functionally safe.

What is RTLC20 scale?

RTLC20 is a low profile stainless steel tape scale featuring a 20 µm pitch and IN-TRAC customer selectable reference mark. It is accurate to ±5 µm/m and in lengths up to 10 metres (>10 metres on request). Two mounting options are available, both allow independent thermal expansion and tape scale convenience.
RTLC20 can be used with the revolutionary FASTRACK™ scale carrier system. This system allows a track to be laid quickly and easily with no need for fixing holes. A sacrificial spacer is removed and the tape scale is then fed into the track.
RTLC20-S is laid onto the substrate with self-adhesive backing tape. The self-adhesive is formulated in such a way that it allows for independent scale expansion to that of the substrate.
To complete the installation, both types of scale are clamped at one point to provide a datum position.

Why choose this encoder system?

Functional Safety certification

The TONiC FS series is an incremental open optical encoder system with certification to the following Functional Safety standards:

ISO 13849 Category 3 PLd
IEC 61508 SIL2
IEC 61800-5-2 SIL2

Certain machinery safety functions, such as Safety Limited Speed (SLS), require the encoder feedback to be functionally safe. Utilising an encoder system that is already rated for use in these applications can make machine certification significantly easier. Adopting these advanced machine safety functions allows machine builders to make safer machines, capable of higher functionality that can reduce set-up times and machine downtime.

Exceptional metrology

The TONiC encoder features Renishaw's market-proven filtering optics and advanced signal processing. Auto Gain Control (AGC) and Auto Offset Control (AOC) technologies reduce analogue signal noise and digital jitter within the readhead.

TONiC encoders deliver exceptionally low signal output jitter of <±0.5 nm RMS and low Sub-Divisional Error (SDE) of <±30 nm, enabling systems to hold position better and generate less heat in linear motor applications. Low jitter also enables smoother velocity control in high-precision applications operating at low speeds.

Flexible configuration

The TONiC series offers a variety of external interfaces that can be configured to meet the speed and resolution requirements of the application. With late-stage integration and configuration of the external interface, one versatile TONiC readhead offers many options for end user customisation.

TONiC interface options enable digital, analogue, or dual output of both digital and analogue signals. The TD (dual resolution) interface offers selectable dual-resolution output, and a DPI interface is also available for wide-format printing applications. The flexibility of TONiC encoder configuration allows OEMs to benefit from superior motion control and high throughput in a wide range of applications.

Interface options

Ti interface

  • Analogue output, including a CAL button.Ti interface

DOP (dual output) interface

  • Provides simultaneous digital quadrature and 1 Vpp signals.
  • Designed for applications requiring one or more operations to be synchronised with a motion axis.TONiC Dual Output (DOP) interface

Optional diagnostic kit

TONiC™ diagnostic kit (software and hardware)

TONiC diagnostic software can be used to optimise the installation of TONiC encoders and provide a quick and comprehensive system calibration. The software must be used in conjunction with the TONiC diagnostic hardware which can be purchased from Renishaw using part number A-9411-0011. The hardware is connected to the PC via the USB cable (provided in the kit) or in-line with the customers' electronics.

Find out all about the TONiC diagnostic kit.

Technical specifications

Measuring standard

FASTRACK RTLC20: stainless steel tape scale with carrier system

RTLC20-S: stainless steel tape scale with self-adhesive backing tape, for mounting directly to a substrate without FASTRACK guide rails

Readhead size (LxWxH)

35 mm x 13.5 mm x 10 mm

Scale pitch

20 μm

Coefficient of thermal expansion at 20 °C

10.1 ±0.2 μm/m/°C

Accuracy grade at 20 °C

±5 μm/m

Reference mark

IN-TRAC reference marks directly embedded into RTLC20 / RTLC20-S

Selector magnet used to identify chosen reference mark

Limit switches

Dual or single limits (select at time of order)

Scale length

FASTRACK: 100 mm to 25 m

RTLC20/RTLC20-S: up to 10 m

(> 10 m on request)

Maximum speed


Digital (*use with DOP)

(See data sheet for details)

Up to 10 m/s at -3 dB

Up to 10 m/s

Sub-Divisional Error (SDE)

Typically < ±30 nm

Dynamic signal control

Real time signal conditioning including Auto Gain Control (AGC) and Auto Offset Control (AOC) for optimised performance during operation

Incremental signals


Digital (*use with DOP)

1 Vpp (20 μm period)

Resolutions from 5 μm to 1 nm

Electrical connection

0.2 m, 0.5 m, 1 m, 1.5 m, 3 m, 5 m, 6 m and 10 m cable lengths with mini connector (connects direct to TONiC interface)

Power supply

5 V ±10%
Readhead only < 100 mA
With Ti0000 < 100 mA
With DOP < 275 mA

Vibration (system)

100 m/s2 at 55 Hz to 2 000 Hz, 3 axes

Shock (system)

500 m/s2, 6 ms, ½ sine, 3 axes

Operating temperature (system)

0 °C to +70 °C


Readhead: IP40
Ti interface: IP20
DOP interface: IP30

* Only the analogue sine and cosine outputs are functionally safe.

Refer to data sheets for full details.