Using A 5V Relay To Control 30V DC Power Source

Hello.

I have designed an embedded system to work as an online voltmeter. Please check the attached image.

Now I want to add a 5 volts relay within the positive terminal of the power source and the 25 kilo-ohms resistor, so that I can control the flow of current with a GSM shield.

My question is, is it possible to do so?

Thanks in advance.

I don't understand what you are saying . How would a relay control current ?
If you don't have electronics experience and you need a relay on/off switch then say so.

FYI, it's called an "SPST switch" .
If it's a relay it's called "a relay wired as an SPST switch".

Don't understand your requirement. If your intention is to switch off/on some devices then yes you can use a relay. Not sure what you meant by controlling the flow of current.

Glad it's not just me, LOL.

Sorry for my vague question. Let me explain further.

I want a switch between the DC power source and the Arduino embedded system. When the switch is closed, the embedded system should be able to measure the voltage (i.e., circuit is complete) and vice versa.

I want to use a 5 volts relay as the switch.

My question is, could my job be done with it?

Thanks.

raschemmel:
I don't understand what you are saying . How would a relay control current ?
If you don't have electronics experience and you need a relay on/off switch then say so.

FYI, it's called an "SPST switch" .
If it's a relay it's called "a relay wired as an SPST switch".

Sami584:
My question is, could my job be done with it?

Yes.

lg, couka

Which brings us to the question:

If you even have to post for this do you know how to wire a 5V relay as an SPST switch and how to control the relay ? Do you have a link for the relay ?

how are you going to control the relay? Arduino is going to do that? Still your requirement is very vague.

Is this some thing you are looking for to read the volt using Arduino http://www.electroschematics.com/9351/arduino-digital-voltmeter/

  1. I assume you will trigger a volt read via ethernet shield
  2. then arduino should switch on a relay
  3. The arduino should be able to read the voltage from the NO pin of the relay.

The above all are my assumption, so please clarify.

The above all are my assumption, so please clarify.

This is the game we like to call "20 Questions" that we often have to play with newbies who don't provide any useful information.

I feel it's because of not enough clarity about what they wanted to achieve or lack of framing the question well enough.

Sami584:
Hello.

I have designed an embedded system to work as an online voltmeter. Please check the attached image.

Now I want to add a 5 volts relay within the positive terminal of the power source and the 25 kilo-ohms resistor, so that I can control the flow of current with a GSM shield.

My question is, is it possible to do so?

Thanks in advance.

Yes, you can control the current (and voltage) from the power supply with a relay. How much current are we trying to control? You can control it ON and OFF! Is that what you want?

You went to an awful lot of work to measure 0-30 volts. A simple two resistor voltage divider will work.

Paul

You went to an awful lot of work to measure 0-30 volts. A simple two resistor voltage divider will work.

30V/25 k ohms = 1.2 mA