Avtron SV850 SAFETach™ Encoder

Avtron SV850 SAFETach™ Encoder

The World's First No-Bearing Safety Encoder!

  • Meets IEC 61508 SIL 2 at HFT 0
  • Installation in Minutes!
  • Up to 5000 PPR
  • Removable Sensors
  • Mounts Securely to Motor
  • No Rotating Seals
  • No Optics
  • Sealed Electronics
  • Self-Diagnostic LED & Alarm Output
  • 3 Year No-Hassle Warranty
Outline Drawing
The SV850 is the world's first safety rated no-bearing encoder for SIL 2 applications. Often, optical encoders fail because of dust or water contamination that prevents the sensor from seeing the optical disk. The SV850 advanced magnetic technology sees through contamination and the fully sealed circuit design ensures your machine keeps working, even in mill environments. The SV850 offers magnetic performance and moisture resistance!

SV850 SAFETach™ III safety modular magnetic encoders fit standard 8.5" FC-Face motors. Quite simply, the SV850 is designed to eliminate encoder failures. All SV850 electronics are fully encapsulated. There are no moving wearing parts.

Miswiring an encoder is common– and it shouldn’t cost you time or money. Wiring errors and short circuits that cause an over-temp situation will be detected and indicated by changing the LED to orange. The SV850 has full output short circuit and reverse voltage protection, plus surge protection.  SV850 SAFETach III sensors digitally self-tune the outputs to eliminate drive trips caused by poor encoder signals.  The universal 5-24V design drives longer cables and is protected against wiring errors and surges.

Adaptive Electronics: At power-up you know you installed it right! The green LED tells you your SV5 Sensor is aligned with the rotor and reading signal.  If at any time, the SV5 cannot produce consistent signals, the LED changes to red and the optional remote alarm contact activates. However, the encoder keeps working to give you time to schedule service.

What good is a competitors "safety" encoder if it's optical and fails? Pick the SV850 for safety and reliability!
Operating Power (Each Sensor): 5-24V
Current: 100mA
Output Format: A Quad B with marker (A,/A, B,/B, Z,/Z) 
Maximum Cable Length: 1000' @ 5V, 500' @ 12V, 200' @ 24V
PPR: 4 - 50000***
Speed: 6000 RPM Max****
Rotor Positioning: Up to +/-0.100" movement/misalignment
Sensor-Rotor Gap: 0.045", +0.015/-0.040" [1.14mm+0.38/-1.0]
Temperature: -40° to 100°C (rotor -40° to 150°C peak)
Electronics: Fully Encapsulated, IP67**
Vibration: 18G
Shock: 1 meter drop test
Weight: 9lbs. [4kg]; 11lbs. [5kg] dual
Safety Level: Evaluated for IEC 61508 SIL 2 metrics at HFT 0

** Certain connector options may reduce IP rating.
***(PPR) Standard maximum PPR is 5000. Consult Factory with your application for PPRs up to 50,000.
****(Speed) Maximum RPM may be limited for PPR > 2,500. Consult Factory with your application.
  • Resists motor and brake interference noise
  • Full protection against short circuits, reverse voltage, phase-to-phase shorts
  • PPR can be factory reprogrammed
  • High resolution up to 5000 PPR
Industry General Food & Beverage Pulp & Paper Wood Products Wind Power Crane & Hoist Metals Mining Marine Oil & Gas

Light Mill Duty

AV20, AV25, AV6A, AV6M, Avtron Elevator Encoder, Cables and Connectors, Encoder Couplings, Encoder Programming Tool, HS25A, HS35A, HS6A, K661, SC65

Mill Duty

AV32, Cables and Connectors, Encoder Couplings, HS35M, HS35X, HS6M, K661, M185, M3, M3(small), RAHS35M

Heavy Mill Duty

AV115, AV125, AV44, AV45, AV56, AV56-Wind, AV56S, AV67, AV85, AV850, AVSK, Cables and Connectors, Carlen Replacement, HS44, HS45, K661, M4, M4(small), XP5, XR115, XR12, XR125, XR45, XR4F, XR5, XR56, XR67, XR85, XR850, XR97, XRB1, XRB2, XRB3

Severe Mill Duty

AV12, AV30, AV485, AV5, AV685, Cables and Connectors, Carlen Replacement, Encoder Couplings, HS40, K661, M484, M6, M6C, M7, XP5, XPH1, XPH8, XR12, XR485, XR5, XR685, XR97, XRB1, XRB2, XRB3,
Adobe Reader

In This Section

  • Bearingless

    These encoders use the bearings of the motor or machine, eliminating a huge source of failure in encoders.  Also known as modular and sandwich encoders.

  • C-Face

    A machined flange or elevated/recessed face provided on motors for mounting accessories. Typically provided on the drive end for gearbox/load mounting, C-faces may also be provided on the non-drive end for mounting encoders, brakes, and other accessories.

  • Contamination

    Also known as contaminants, such as water, dirt, dust, oil, and other compounds which enter an encoder through seal failure and can cause optical errors. If the contamination is abrasive, it can also cause bearing failures in the encoder. Modular encoders are very resistant to contamination as they use magnetoresistive sensors and have no bearings.

  • Functional Safety

    Functional safety is the part of the overall safety of a system or piece of equipment that depends on automatic protection operating correctly in response to its inputs or failure in a predictable manner (fail-safe). The Avtron SV850 Encoder features SIL 2 rating and a no-bearing design.

    Avtron SV850 Encoders are suitable for:

    SAR – Safe Acceleration Range,
    SBC – Safe Brake Control
    SDI – Safe Direction Indication
    SLA – Safe Limited Acceleration
    SLI – Safe Limited Increment
    SLS – Safe Limited Speed
    SOS – Safe Operating Stop
    SSM – Safe Speed Monitor
    SSR – Safe Speed Range
    SS1 – Safe Stop 1
    SS2 – Safe Stop 2
    STO – Safe Torque Off

  • Magnetic Rotor

    A magnetized disk with multiple north and south poles lined up around the perimeter of the disk. A magnetoresistive sensor detects the transitions and generates the pulses generated by the magnetic encoder.

  • Modular Encoders

    Modular Encoders mount to a machined C-face or flange adapter on the motor (drive or non-drive end). Modular encoders consist of a rotor that mounts on the shaft, and a stator that bolts to the motor frame. Modular encoders are very rugged, and Avtron encoders feature Wide-Gap sensors to avoid complex shimming or fitting to the motor. Modular C-face encoders are typically used on DC motors; but some AC motors, such as Rockwell’s RPM III AC and Marathon’s Blue and Black Max motors, have C-faces standard on the non-drive end for mounting an encoder.


    A NEMA FC face mount is a 8.5" flange with (4) bolts located in a 7.25" circle. Originally used for mounting solid shaft, coupled tachometers using flange adapters, the NEMA FC 8.5" face is a standard for mounting modular encoders. (Drawing "A") Avtron AV85 and AV850 encoders mount directly on NEMA FC 8.5" faces. (Drawing "B")

  • UL Recognized

    UL Recognized Avtron encoders are usable for OEM applications requiring UL Class I, Division 2.  The OEM must select the model which meets the application requirements, and ensure that the system as a whole meets the application and safety requirements.  Note that UL Recognition is a different system than UL Listing, ATEX or IECEx.  Most Avtron XR encoder models are available in both UL Recognized and UL Listed versions.  UL Recognized XR encoders offer a broader range of connector options than UL Listed XR encoders.

Contact Avtron

Contact Us