# DC Voltage Needs logging to dBase

Hi - I have a number of laser micrometers (most of which are 0 - 15v output (dependant upon diameter observed), while I have another that is -5vDC - +5vDC.

I would like to be able to input the ‘variable’ voltage into the Arduino Uno, and based on the input, a conversion will be applied (for example: 5v = 10mm, and 15v = 18mm) - I need to :

1. Convert the voltage into something the Arduino can manage,
2. have the Arduino ideally convert the data to a dimensional value,
3. transfer the data to a database (preferable m\$ access - or if needs be, something like xampp)

Any advice, guidance would be appreciated.

1) Use a voltage divider, see - http://en.wikipedia.org/wiki/Voltage_divider - for 15V -> 5V you need

15V -- 20K --+-- 10K -- GND

2) Arduino reads 0..1023 == 0..5V float voltage = 5.0 * analogRead(A0) /1023.0;

3) Check - http://www.mikmo.dk/gobetwino.html -

Succes

Advanced thanks - I shall try and give this a go next week. (Or at least my "student" will)

Will update if we get success, or if extra guidance is required.

Thankyou

For those that are interested - We have had a level of success on this project (Have made a voltage divider that sits like a shield on the Arduino Board)

Voltage in is 0 - 10v, so a nice simple divider was implemented - only problem is resolution - as 10v = 40mm, and most of what is measured is at 20mm top end (after voltage division = 2.5v (511 digital)… Any way, we are using “plx_daq” to communicate with Excel, which automatically produces a histogram with Distribution plot, and updates the CP / CPK / MEAN / STdev etc… and a live run chart that shows the last 20 results including the min and max of the 200 samples taken in the 1 second snapshop - this has been tested on about 40kilometers of product, and works well.

If anybody can suggest or better our structure, please feel free to do so - LET US KNOW as we want to improve more… ideally get the arduion to calculate stdev on its own on the run

const int Analog_In_Pin = A1 ;

double Calibration = 1.0215 ; // Due to Resisistor Variances on Voltage Divider - Used to align with Known Diameter Output against Calibration Pins (6.00mm - 25.00mm)
double Storing_Array_Digital[200] = {} ;
double Storing_Array_Analog[200] = {} ;
double *Pointer_Digital ;
double *Pointer_Analog ;
double Output_Analog ;
double Output_Digital ;
double Sum ;
double Average ;
double Max_Digital ;
double Min_Digital ;
double Max_Analog ;
double Min_Analog ;
int i = 0 ;

void setup() {
Serial.begin(9600) ;

}
void loop() {
Sum = 0 ;
Average = 0 ;
for ( i = 0 ; i <=199 ; i = i +1 ){

// C A L I B R A T I O N S T A R T
// C A L I B R A T I O N E N D
Sum = Sum + Analog_Reading ;
_
Average = Sum/200 ;*_

* if ( i == 0) {*
_
}_
if ( i != 0 && Digital_Reading > Max_Digital ){
_
}_
if ( i!= 0 && Analog_Reading > Max_Analog) {
_
}_
if ( i!= 0 && Digital_Reading < Min_Digital ) {
_
}_
if ( i != 0 && Analog_Reading < Min_Analog) {
_
}_
_
delay(5) ;_
_
} *_

_ Average = Average8 ;_
Min_Analog = Min_Analog8 ;

Max_Analog = Max_Analog8 ;
_
Serial.print(“DATA”) ;_
_
Serial.print(",");_
_
Serial.print(Average,5);_
_
Serial.print(",") ;_
Serial.print(Min_Analog,5) ;
_
Serial.print(",") ;_
Serial.println(Max_Analog,5) ;
_
}*_