DESIGNER’S HANDBOOK 4189350049C EN
Page 69 of 206
In this example the potentiometer is supplied by a 10V DC voltage and the output swing is therefore
0 to 10V. This means that an artificial zero must be inserted as an analogue input centre value. This is to make the
input swing symmetric around this centre point. In this case the analogue centre point is 5.000V =5000 mV.
To make room for the input voltage swing up to 10V the +/-15V input voltage range is selected.
This configuration will automatically adjust to the max voltage range, as long as it is inside the max. input range, but
please note that the measurements will be performed with the input centred at 5.000 V and in this application the
supply voltage must be relatively stable to give an accurate performance.
5.6.9.5 Double triangle input, Vref as supply for potentiometer
In the following example the double potentiometer is connected to Vref on the AX1 module.
In this case XDi will measure Vref
and automatically set the
analogue centre value to ½ Vref.
The voltage input range could be selected as +/-7.5V in this case.
Connection of the potentiometer
Terminal 1: AX1 AGND
Terminal 2: To AX1 +HV2 input
Terminal 3: AX1 Vref output (app. +7.4V)
Terminal 5: To AX1 +HV1 input
Potentiometer is shown at 0°
