# Arduino Forum

## Using Arduino => Project Guidance => Topic started by: oKeeg on Dec 15, 2018, 04:21 am

Title: Arduino Nano DC to AC
Post by: oKeeg on Dec 15, 2018, 04:21 am
Hello,

I am quite a noob with the arduino still but I am wondering if it is possible to press a button on the arduino and receive 40v AC current.
If it is, could someone explain the schematics and any extra components I need
Thank you for your patients with me  :smiley-lol:
Title: Re: Arduino Nano DC to AC
Post by: Railroader on Dec 15, 2018, 05:35 am
Try a solid state relay switching on a 40 volt mains transformer.
Title: Re: Arduino Nano DC to AC
Post by: ChrisTenone on Dec 15, 2018, 05:40 am
It's not really clear what you mean by "receive 40v AC current". Do you mean powered by 40 volts AC? Or detect it?

Either way, you would need the components needed to convert it to 5 volts DC. This would likely entail a transformer, a rectifier, a filter, and then a voltage regulator. Here's a schematic I found by googling AC to 5 volt DC:
(https://dl.dropboxusercontent.com/s/7hwa4oc72ckxaf4/psdiagram.gif)
Title: Re: Arduino Nano DC to AC
Post by: sterretje on Dec 15, 2018, 05:41 am
It's not quite clear if the Arduino needs to read a 40V AC or to create a 40V AC signal.

1)
For reading 40V AC, you can rectify the AC signal (4 diodes and an electrolitic capacitor) followed by a voltage divider (https://learn.sparkfun.com/tutorials/voltage-dividers/all).

The rectifier/capacitor will create a DC voltage of roughly 56 Volt from the 40V AC and the voltage divider needs to be calculated in such a way that it reduces the DC voltage to 5V. E.g. 10kOhm from 56V to Arduino pin, 1kOhm from Arduino pin to ground.

2)
For generating 40V AC, you will need to provide a little be more detail and it will not my area of knowledge. With the little info that you gave, if tou have a 40V AC signal available, you can switch it on/off with a relay.

PS.
I see that Chris did beat me to it. Not sure if th LM7805 is needed.
Title: Re: Arduino Nano DC to AC
Post by: oKeeg on Dec 15, 2018, 06:29 am
I would like the end result to be 40v AC.. sorry for the confusion. I will try a relay system and try to figure it out. Thank you!
Title: Re: Arduino Nano DC to AC
Post by: ChrisTenone on Dec 16, 2018, 05:35 am
In that case, you need to specify the frequency, and if a square wave is sufficient, or do you need a sinusoidal output. The latter will be more difficult to put together.
Title: Re: Arduino Nano DC to AC
Post by: TomGeorge on Dec 16, 2018, 08:49 am
Hi,
What is the application?
What do you need the 40Vac for?