Phidgets Forums

I am using the 1135 Precision voltage sensor to monitor a 6 VDC battery pack using the 1018 Interface kit to connect to RPI 3 I am using the C language VoltageInput example. The example consistently displays a 2.8938 value. Using a DVM to measure the battery pack indicates the voltage is at 5.91 VDC. I used a formula found on the Phidgets website which subtracts 2.5 from the input voltage and then divides that result by .0681 I assume I'm using this formula correctly but the formula is off by .13 of a volt. Thus, how can I convert the output of 2.8938 to 5.91 VDC?

Problem resolved. I disconnected the 6VDC power pack from the 1135 Precision voltage Sensor and ran the example program. It displayed a value of 2.4884. Thus, I replaced the 2.5 in the formula with 2.4884 and the problem is resolved.