Reading DC voltage with UNO

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mjpcarbon
 
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Reading DC voltage with UNO

Post by mjpcarbon »

So for my next upcoming project since this is so kool I would like to know if we can read DC voltage with our UNO ? and if so how high
Final goal would be to read voltage and adjust a linear actuator to keep a given height based on changing voltage.
I hope I have explained this well enough

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adafruit_support_bill
 
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Re: Reading DC voltage with UNO

Post by adafruit_support_bill »

The analog pins on the UNO can directly measure 0-5v DC. For voltages higher than that, you can usually scale them down to the 0-5v range using a voltage divider. http://en.wikipedia.org/wiki/Voltage_divider

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mjpcarbon
 
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Re: Reading DC voltage with UNO

Post by mjpcarbon »

Bill at the moment that is over my head I am embarrassed to say.
If I do move forward if I measure the actual voltage perhaps I can get help with the resistors needed etc.
As always thank you

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adafruit_support_bill
 
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Re: Reading DC voltage with UNO

Post by adafruit_support_bill »

There are lots of resistor divider calculators on-line. And if you have an iPhone, there is also one in our Circuit Playground App: http://www.adafruit.com/circuitplayground
And if you are still stuck, by all means, ask on the forum. :)

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mjpcarbon
 
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Re: Reading DC voltage with UNO

Post by mjpcarbon »

I will download the app and try to figure it out myself.
I measured the VDC and the range is 112vdc-160vdc

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adafruit_support_bill
 
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Re: Reading DC voltage with UNO

Post by adafruit_support_bill »

I measured the VDC and the range is 112vdc-160vdc
That is a fairly wide range - and a fairly high voltage. Use care when working with voltages in this range. They can be lethal.

And err on the side of safety when when calculating your voltage divider. To avoid damage to the Arduino, you want to make sure that the voltage to the analog pin is 5v or less.

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mjpcarbon
 
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Re: Reading DC voltage with UNO

Post by mjpcarbon »

I agree, I will use a meter until I am certain of the in and out voltages.
My next question if I get it close will be how to move a linear actuator will the voltage.

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Re: Reading DC voltage with UNO

Post by adafruit_support_bill »

My next question if I get it close will be how to move a linear actuator will the voltage.
We'll need some more detail about your actuator and how you need it to move in response to the voltage change.

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