Glossary of Technical Terms

A list of terms and definitions you may find helpful.

Absolute Rotary Encoder

An electromechanical device converts the angular position into digital data, which is retained when electrical power is removed. It can also be used to determine linear position and speed/acceleration.

AC [~]

Alternating current.

Alarm Signal

Serves to monitor the shaft encoder for malfunctions, such as glass breakage, short circuit and insufficient line voltage.

Analogue Signal

An output signal which alters continuously.

Axial Loading

Maximum load on the encoder’s shaft in the axial direction.

Baud Rate

Rate of data transfer (bits per second) expressed in Mbaud, i.e. 12 Mbaud.


Operating in two directions.


Two logic states (Yes/No) are the basis of binary data processing systems.

Binary Code

Code using binary numbering is often used for absolute measuring systems.

Bistable Signal

The output signal is present until the reset conditions are met.


Abbreviation for “Binary Digit” where the logical value is expressed as 0 or 1 to give a yes or no decision.


Brushless DC Motor.


System for communication between several devices through a data line.


A sequence of 8 bits.


Clockwise or Counter Clockwise.


An electronic circuit with encoder outputs to invert two channels and express a voltage difference between two lines, thus removing interference along transmission cables that connect an incremental encoder with its controller.


Count correction.

Counting Rate

See count frequency.

Count Frequency

The number of count pulses per second [Hz].

CSA Approval

Approval by the Canadian Standards Association.

Data Integrity

Correspondence of data with the reality they describe.

DC [=]

Direct current.



Direction BW

BW shaft rotation, viewing the front display, the top of the rotary shaft is going away from the observer.

Direction BZ

BZ shaft rotation, viewing the front display, the top of the rotary shaft is coming towards the observer.


Blocking of a function.

Duty Cycle [ED]

The ratio of pulse length to non-pulse period, a 40% duty cycle, the pulse length is 4/10 and the non-pulse period 6/10 of the total time.


See duty cycle.


Electromagnetic compatibility.


See inhibit.

Gray Code

Only one data bit change per measuring step at a time.

Incremental Rotary Encoder

An electromechanical device which converts the angular position into data (pulses determined by a marked disk). It can also be used to determine linear position, speed & acceleration. Incremental encoders do not retain positional data on the removal of power.




Blocking of the counter input during counting operation.


The interface is used for communication between the counter and external systems. Count values can be input or output via the interface.


See Protection Class.


Blocking of keyboard inputs.

Key Reset

The reset button can only be operated using a key.


Liquid Crystal Display. A passive display requiring external light or backlighting to be read.


Light Emitting Diode. An active display lights up as long as a supply voltage is fed to the device.


Least Significant Bit.

Monostable Signal

The out signal is active for a defined period.


Most Significant Bit.


Not connected. Defines unassigned connections in diagrams.


Transistor input/output circuit implemented with NPN transistor, thus negative switching.

NV Memory

Non-volatile; electronic non-volatile memory for electronic counters is used for value retention in case the supply voltage is interrupted.

OFF Delay Timing (Pneumatic Timers)

The OFF is delayed. The output valve is positive while timing and negative on timeout, referred to as open valve timing.

ON Delay Timing (Pneumatic Timers)

The ON is delayed. The output valve is negative while timing and positive on timeout referred to as closed valve timing.


Output (preset, zero, signal).

Parallel Interface

Transfer point at which the data is transferred in parallel over several lines.


Transistor input/output circuit implemented with PNP transistor, thus positive switching.


Pulses Per Revolution.


The factor by which the incoming pulses are multiplied.

Preset Counter

Counters with control functions.


See Prescaler.

Protection Class

An IP rating is a two-figure code number, for example, IP40, the first digit being the degree of protection against the ingress of solids and the second digit being the degree of protection against water.


Polyvinylchloride, a plastic coating of device cables.

Radial Loading

Maximum load on the encoder’s shaft in the radial direction.

Reference Pulse

A square wave signal is generated by a reference mark, usually only one increment wide, to provide an absolute reference for an incremental encoder.


Reset, see reset.


Resetting of a counter to its initial value.


A device for monitoring an electric motor’s speed and angular position is usually integrated into the rotor shaft and is sometimes known as a motor feedback controller.


The sense lines (Sense VCC and sense GND) enable measurement of the factual encoder voltage without adulteration by a voltage drop due to supply current and cable resistivity. With that, e.g. supply voltage can automatically be adjusted.


Applying force acting at a radial distance from a central point causes rotation.

Totalising Counter

A counter which only adds up received pulses without a control function.


Thermoplastic polyester elastomer, a plastic coating of device cables.

Transmission Ratio

The first number indicates the rotation of the shaft, and the second number shows the count value in the display.


Operating in a single direction.