I am trying to use the arduino as a Voltage Reference input to output and activate a relay.
The Arduino would Vref 0v-4.8VMax analog input.
At 4.8vref only the arduino would signal activation of a relay which in turn would activate a 12v source.
Is this capable?
Your description of the problem is hard to interpret - especially your use of the term Vref
The Arduino could measure a voltage that varies in the range 0 - 4.8v and when a particular voltage is detected it could activate a relay.
If that is not a useful comment then please explain your problem more clearly.
Vref= Voltage Reference
What you said Robin2 is just that.
The voltage from a GM Throttle Position Sensor (TPS) is 0v-4.8v out put.
I would like to use an arduino to monitor the output voltage from the TPS and when it reaches 4.8v to send a signal to a 12v relay activating a 12v switch.
In the big scheme of things the arduino is going to be used to activate a N2O system safely.
it will also be sending out information to an LCD screen and LEDs.
I figure I will need to use an Arduino Mega to handle all of the I/O information.
1st Signal is from the manual arming switch
2nd Signal is from the TPS, giving a min 4.8v reference
3rd Signal is from the ignition system when it reaches 3000RPM min reference.
4th Signal is from the nitrous pressure transducer giving a 1200-1500psi reading
5th Signal is from the Fuel Pressure Sensor giving a min 45psi reading
6th Signal is from the Oil Pressure switch giving a positive pressure reading
quote: "The voltage from a GM Throttle Position Sensor (TPS) is 0v-4.8v out put.".
Have you looked at this signal with an oscilloscope to be sure there is no noise on the signal and how quickly the voltage can change? Your Arduino will also see the noise and may or may not catch rapid voltage changes.
Vref= Voltage Reference
Yes, I did figure that.
But "Vref" has a very specific meaning in the context of an Atmega328 microchip. Is that the sense in which you are using the term?
You might also want to hardwire interlock some of the system - e.g switch on the throttle hardwire linked to the n2o valve etc to improve safety for when the Arduino crashes .
You seem to have edited your Original Post after Reply #5 was posted. What change did you make?
When halfway through reading a story nobody wants to have to go back to the start.
If the reason for the edit was only to correct a typo that's fine. But if you made a substantial change then it will make a nonsense of the earlier comments so please reinstate the original text.
Then you can add your additional information or clarification in your next Reply.