Change of state For CAN: Bus node (encoder) sends it's data automatically when a position change occurs.
Channel Signal track on which 1 or 0 is outputted.
CiA CAN in automation (CAN users and manufacturers group)
CiA DS CAN in automation draft standard, communication profile
CiA DSP CAN in automation draft standard proposal, communication profile
CIM Computer Integrated Manufacturing; i. e. the linking of different computer-aided processes in production and related fields for general use of the data.
CMD Software tool for configuration and diagnosis of Interbus networks
COB Communication object
Code Format in which data are transmitted.
Code switching frequency Number of position steps per second. For absolute shaft encoders with parallel interface: The maximum output frequency of the LSB output driver (fmax) also limits the maximum permissible code switching frequency: Code switching frequency max. = 2 · fmax for Binary code Code switching frequency max. = 4 · fmax for Gray code
Coefficient of thermal expansion Material expansion under influence of temperature change [µm/°K m], relevant for linear scales.
Coincidence Accordance of set value (preset) and actual value (count)
Coincidence mode See operating mode
Complementary Output circuit for which also the inverted signals are outputted (e.g. Channel A and Channel A). Electrically, the 1/0 levels are transmitted as voltage differences between two lines. In this way the information signal (the difference) remains pure as in general interferences are interspersed equally on both lines.
Connection box In modular system 400 (plug-in type counters), the term "connection box" is used for the insert socket of the counter (see, for example, the totalizing counter in the modular system).
COR Count correction
Count Display of counted value (actual value) at the counter.
Count correction Correction of count; correction is not stored.
Count input – Differential
For adding, subtracting or differential count. The counter is equipped with a subtracting and an adding input.
- Count direction
For adding, subtracting or differential count. The counter is equipped with a count input and a counter advance sense input.
– Phase discriminator
For forward/backward counting. The counter is equipped with a 2-channel input. Signals are phase-shifted by 90° to allow counter to recognize count advance sense automatically. The count input can be programmed for single, double or 4-foldevaluation.
Counter advance sense input See count input
Counter advance sense signal Output signal of the counter; can be used independently of counter advance sense for control purposes (e.g. drive unit control). The counter advance sense signal operates independently of OUT signal status.
Counting frequency [f] Number of count pulses per second [Hz] In pneumatic counters, the non-pulse period must be long enough to allow pressure to drop to approx. 0.15 bar for a minimum of approx. 12 ms.
Approximately 12 pulses/s are reached in a pressure range of 6 bar and at an ambient temperature of 20 °C.
Increasing flow or length of tubing reduces maximum possible counting rate and thus also warming.
Counting mode In mechanical counters only: (+) adding in the specified sense of rotation + (–) adding in the specified sense of rotation; subtracting in the reverse direction + (+) adding in both senses of rotation – (–) subtracting in the specified sense of rotation; adding in the reverse direction
Counting rate See count frequency
CRC Cyclic redundancy check. Bit error protection method for data communication.
CSA approval Approval by the Canadian Standards Association