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IO-Link: Did You Know?

Did you know that the signal quality of measuring sensors can be increased with IO-Link?

IO-Link enables reliable, loss-free signal transmission from the sensor to the controller.

Background: When an analog signal is transmitted to the controller, several conversions from analog to digital and from digital to analog are necessary. Each of these conversions affects the quality of the transmitted process value. Furthermore, the signal is affected by electromagnetic interferences. Unfortunately, it is common practice in the real world for signal lines to be routed together with, and not separate from, power cables. If, in addition, the shield is not implemented properly, the quality of the transmitted process value is affected.

Result: The signals measured at the sensor tip do not reach the controller. The accuracy that could be achieved through the use of high-quality sensors is therefore lost along the transmission path.

The situation is completely different with IO-Link. A major advantage of IO-Link is that it needs only one conversion. The analog signal from the sensing element of the measured quantity is converted to a digital signal. The signal is then processed and transmitted from the sensor to the controller via the IO-Link master only as a digital signal. Conversion losses are thereby prevented. The signal measured at the sensor tip reaches the user program without loss of quality. The signal quality is continuously monitored for assurance purposes. An additional secondary effect is that the plant operator or service technician receives the same measured values both on the measuring device and on the plant display.

Additional advantage: The digital signal transmission cannot be affected by electromagnetic disturbances. This means that costly shielded cables are no longer necessary. IO-Link can be used cost-neutral compared with the previous analog technology.


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