Hi all I have a question about a pot.
I have a pot currently being used on an inverter to drive a motor. Gnd 10v and variable. Can I use this pot to also be read by an arduino? I am asking about the electrical theory side of this.
Thanks
If you watch your connections and make no nasty groundloops you should be fine.
If we imagine that your pot is connected to the VFD with three pins and one of them is ground, this is how i would do it:
Power the Arduino from a seperate power supply (USB "charger" is handy)
The inputs on the typical Arduino can not tolerate more than 5V maximum, so we need to halve the 0-10V signal.
You need a voltage divider that's 10 times higher in resistance than the pot to not affect the pot too much.
e.g. with a 10K pot on the VFD, make a voltage divider with two 100k resistors and feed the midpoint of it to analog-in on the Arduino.
// Per.
Note that a pot is also a voltage divider... At the mid-position you should get 5V out. (That's assuming a linear, which most pots are... Volume controls are approxmately logarithmic/exponential.)
If this is a VFD it will be connected to mains. You need to be absolutely sure the pot ground pin is
mains ground (or safely isolated) before connecting to it, if its mains neutral (for instance) you are
risking life and limb.
Hi all thanks for the advice.
I will build it with a VFD I'm more familiar with and process to test.
Mark I'm pretty confident it is an isolated 0V and 10V
I will check the schematics etc and update you all
Thanks
10V is more than the Arduino can handle.