Connection of active-type analog sensors (voltage) with no electrically \ isolated power supply

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Connection example

Caution

The potential difference between AGND and ZP at the module must not be greater than 1V, not even in case of long lines AI523 - Analog Input Module.

Note

If AGND does not get connected to ZP, the sensor current flows to ZP via the AGND line. The measuring signal is distorted, as a very low current flows over the voltage line. The total current through the PTC should not exceed 50 mA. This measuring method is therefore only suitable for short lines and small sensor currents. If there are bigger distances, the difference measuring method has to be preferred.

The following measuring ranges can be configured AI523 - Analog Input Module AI531 - Analog Input Module

Voltage 0…10 V 1 channel used
Voltage -10 V…+10 V *) 1 channel used
*) if the sensor can provide this signal range

The function of the LEDs is described under Displays AI523 - Analog Input Module.

In order to avoid error messages or long processing times, it is useful to configure unused analog input channels as “unused”.