Absolute indicates the position of the rotor or shaft referenced to a fixed starting position. If power is turned off and then on, the encoder recalls the position correctly. It may output the position information on a set of output wires (parallel), or it may output the absolute position using a communications bus, such as Profibus or DeviceNet. Absolute encoders can be single-turn or multi-turn. For more information, Wikipedia:  http://en.wikipedia.org/wiki/Rotary_encoder

Absolute Position indicates the position of a rotor or shaft referenced to a fixed starting position. Resolvers and absolute encoders can provide absolute position feedback.

Encoder accuracy is the ability of or limit to the encoder to repeat the exact same signals, given the exact same mechanical position.  Accuracy and resolution may be independent--an encoder can have higher accuracy than resolution, and vice versa.  Avtron incremental encoders are typically accuracy rated at +/-1 count of their resolution; Avtron absolute encoder accuracy varies by model.

A flange used on European IEC frame motors to mount encoders (analogous to the NEMA 56C flange).  6 holes are located on a 100mm bolt circle, surrounding an 85mm flange.  Avtron offers both the AV44 and AV45 heavy duty encoders which directly fit the B10 flange, as well as the AV115 bearingless encoder which can be adapted to the B10 flange.

This is the sine-cosine encoder equivalent to PPR. It indicates the number of sine waves output per revolution, and does not count the cosine waves. Some vendors also use CPR as an equivalent to PPR for digital incremental encoders.

DeviceNet is a fieldbus used by Avtron absolute encoders to report position and speed to a controller.  DeviceNet uses a 4 wire main bus+drop wiring system (CAN).  DeviceNet is hardware-identical to CANopen and J1939, but the encoder messages sent are different.  For encoder communications, SSI, Ethernet, or Profibus may be faster than DeviceNet.  For more information on DeviceNet-Wikipedia:  http://en.wikipedia.org/wiki/Devicenet

A device which indicates position and speed via a set of digital outputs. Incremental encoders output quadrature (A Quad B) signals, and may add a marker pulse once per revolution.  Absolute encoders typically indicate position via a digital message, a set of parallel outputs, or analog values.

EnDat is a proprietary protocol used for some absolute encoders.  EnDat encoders are only manufactured by one company, eliminating competition.  Most controllers which support EnDat also support SSI, which is a open protocol to all vendors and is used by Avtron absolute encoders.

A Fieldbus (communications wiring hardware and software standard) is used to carry absolute encoder signals to the control system.  It may do so automatically on a clock signal input to the encoder (SSI), or in response to a message (ex:  Profibus, DeviceNet).  For more information on fieldbuses:  Wikipedia:  http://en.wikipedia.org/wiki/Fieldbus

Heavy Mill Duty encoders are designed to withstand temperature cycling, extreme temperatures, contaminants, bearing loads, and physical force.

J1939 is a fieldbus used by Avtron absolute encoders to report position and speed to a controller.  J1939 uses a 4 wire main bus+drop wiring system (CAN).  J1939 is hardware-identical to DeviceNet and CANopen, but the encoder messages sent are different; J1939 is primarily used on mobile vehicles.  For encoder communications, SSI, Ethernet, or Profibus may be faster than J1939.  For more information on J1939-Wikipedia:  http://en.wikipedia.org/wiki/J1939

Light Mill Duty encoders are designed for industrial applications but must be protected from contamination, temperature cycling, and physical force, including shock, vibration, and bearing loads. Examples include AV20, AV25, HS25A, and HS35A models.

Magnetic and magnetoresistive encoders typically use a magnetized rotor with north and south poles lined up around the perimeter of the disk. A magnetoresistive sensor detects the transitions, and these are the counts or pulses generated by the encoder. Magnetic encoders withstand dirt, dust, water, and temperature changes far better than optical encoders.

Multiturn refers to the capability of an absolute rotary encoder to output the position accurately including how many times the shaft has been rotated.  The absolute encoder will report this position correctly, including both the position within 1 revolution as well as the total number of turns, whether the encoder was powered when the turns took place or not.  Avtron multiturn absolute encoders do not use batteries, and Avtron absolute magnetic encoders do not use gears for maximum reliability.  Example:  Avtron AV30 severe duty absolute encoder.  For more information on absolute rotary encoders-Wikipedia:  http://en.wikipedia.org/wiki/Rotary_encoder.

An Optical Encoder typically uses a light source shining through, or reflecting off, an optical disk with lines or slots that interrupt the beam of light to an optical sensor. Electronics count the interruptions of the beam and generate the encoder’s output pulses.

Parallel outputs are used by some Avtron absolute encoders to communicate the position to a controller.  One wire is used for each bit of resolution, plus one wire for each turn for multiturn units.  Parallel outputs are used for older controllers; newer controllers typically use a communication fieldbus (such as SSI or Profibus) to read the encoder position.

Powerlink is an Ethernet-based absolute encoder communications hardware and software standard used by Avtron absolute encoders.  For more information about Powerlink-Wikipedia:  http://en.wikipedia.org/wiki/Ethernet_Powerlink

Profibus DP is a fieldbus used by Avtron absolute encoders to communicate speed and position to a controller.  For more information about Profibus DP-Wikipedia:  http://en.wikipedia.org/wiki/Profibus

Profinet (IO) is a communications fieldbus used by Avtron absolute encoders to communicate speed and position to a controller.  Profinet carries Profibus messages over an Ethernet network to and from the encoder.  For more information on Profinet-Wikipedia:  http://en.wikipedia.org/wiki/Profinet

Resolution describes how many individual slices or positions can be reported by an incremental or absolute encoder.  For incremental encoders the number of PPR (pulses per revolution) expresses resolution; for absolute encoders, PPR, or counts per turn or bits of resolution may be listed.

An incremental device typically used to indicate rotary position and velocity. A sine-cosine encoder outputs a preset number of cycles per revolution (CPR) of analog sine waves, along with cosine waves (offset by 90°). Most sine-cosine encoders output ~1V peak-to-peak. Nidec Avtron does not presently offer sine-cosine models because sine-cosine signals are very vulnerable to electrical interference.

SSI (Synchronous Serial Interface) is a fieldbus used by Avtron absolute encoders to communicate speed and position to a controller.  SSI is extremely simple and fast.  SSI is also an effective, open vendor alternative to proprietary encoder fieldbuses such as EnDAT and HyperFace.   For more information about SSI-Wikipedia:  http://en.wikipedia.org/wiki/Synchronous_Serial_Interface

Wiegand wires generate a pulse of electricity in a coil as a magnet passes near the wire.  Wiegand wires are used in Avtron absolute magnetic encoders to self-power the multi-turn counting engine, so even if the encoder has no power when turned, the absolute encoder correctly reports the number of turns and position.  This allows Avtron to eliminate the glass disks and gears that cause failures in other absolute encoders.  For information on the Wiegand effect-Wikipedia: http://en.wikipedia.org/wiki/Wiegand_effect , Wiegand wire: http://www.epanorama.net/sff/Power%20Electronics/Transformers_and_Magnetics/Magnetics%20-%20Wiegand%20Wire.pdf