Here is picture: https://plus.google.com/113684285877323403487/posts/7tKY3Yg6yD6
@donkjr Ah its the 3 pin meter (VCC/VIN/GND?), could this be done with a 2 pin meter (VIN/GND) as I have half a dozen of them sitting in a box doing nothing!
Point me to the one you are using?
Thanks Don. I have a few of these ones
Those meter will work i.e. but not get you what you want.
The pot we are measuring across adjusts the input to the LPS from 0-5VDC. This is measured at the center tap.
The meter you pointed me to measures from 2.5- 30VDC. This means that the DVM will likely not turn on until the pot is about 1/2 way through its travel. (not actually 1/2 cause the pot is nonlinear). These meters use the input voltage to power them so they cannot read anything below the voltage needed to turn them on.
That is why I use the 3 wire. In the 3 wire DVM the voltage to power the meter is independent of the voltage it is measuring therefore you can measure from 0.
If you take the wiper of the pot to an analogue input on an arduino say A0, the 0-5v input will give 0 - 1023 when you read A0 but then using the arduino’s map command you can easily map 0-1023 to 0-100 and there you have your power as a %
make two variables
laserValue ( to hold raw value from input)
laser( to hold remapped value)
laserVal = analogRead(A0); //read the pot value 0-1023 from analogue 0
laser=map(laserVal,0,1023,0,100); // remap it 0 - 100
now just ouput the variable laser to an LCD
I have a 4 line LCD that shows
Laser power
Coolant Flow Rate
Ambient Temp
Coolant temp
and Delta T ( the difference between the two temps)
here it is working https://www.dropbox.com/s/0g4v44z9vqbzmfy/20170625_193838.mp4?dl=0