I'm planning on using some potentiometers as sensors - basically wipers that (for example) sweep from 0-10kohm.
What's the best way to connect them?
- Power from DL1 5v ref or 12v car wiring harness?
- I assume a resistor in series (eg on the +ve line) would be appropriate to avoid shorting; so resistance from Power to pot goes from (X + 0)Ohm to (X+10K)ohm. What's the calculation for an X that maintains good resolution but does not draw too much current? How would it vary if I use a potentiometer with a different range?
Thanks!
Loving the new DL1!
Alex
Connecting resistive sensors
You need a voltage divider circuit. Google it if your not familiar.
You definitely need a regulated voltage source, if you use the built in one keep in mind the limited current capacity or you can use a stand alone one (ex. Radio Shack 7805). Car 12v fluctuates and would render your data useless.
You can check the current draw with Ohm's law (I=V/R).
Set up a spreadsheet and you can quickly run through a couple options. There's even a few online calculators but it's much easier to keep track of what you've looked at with a spreadsheet.
You definitely need a regulated voltage source, if you use the built in one keep in mind the limited current capacity or you can use a stand alone one (ex. Radio Shack 7805). Car 12v fluctuates and would render your data useless.
You can check the current draw with Ohm's law (I=V/R).
Set up a spreadsheet and you can quickly run through a couple options. There's even a few online calculators but it's much easier to keep track of what you've looked at with a spreadsheet.
Jeremy Lucas
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