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

The following figure shows the connection of active-type sensors (voltage) with no electrically isolated power supply.

1 analog input requires 1 channel

Caution

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

Note

If AGND does not get connected to ZP, the sensor current flows to ZP via the AGND line. The measuring signal is distorted, since it flows a very little current 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 Analog Input Module AI523 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 Analog Input Module AI523.

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