Water flow sensor to volt free contact via relay?

I am a total newbie to Arduino but think it could help out with some equipment we need so please be gentle.

I need to control some mobile dosing pumps to dose chemical input based on water throughput.

I am currently using a standard water meter with reed switch that gives a non volt contact when the magnet closes the switch and then breaks this contact as the magnet moves past.

The dosing pump reads these contacts and does the dosing calculation bit pretty well and we get good results. The trouble is the water meters are very heavy and cumbersome and the kit need to be very mobile.

I am looking at hall effect meters but these cannot replicate the same open\closed volt free contact.

My idea was to build a small flow measuring device that counted the pulses from the hall effect flow meter (relatively easy it seems) and then every say 100 hall effect pulses momentarily closed a relay (opening it again almost instantly). The momentary closing of the relay would provide the volt free contact circuit I needed (I think)

We could even link it with an lcd to monitor flow rates.

Is this feasible as any programming would need to keep running as we might need thousands of contacts for a job and near in mind as yet I have never programed anything like this in my life.

Thanks in advance.

I would start with an Arduino UNO, LCD shield with buttons (so you can change dosing), and a flow sensor from ebay.
And ofcourse a 7.5volt (or 9volt) regulated plugin supply for the DC socket.
You also might need a one- or four relay board if your pump is mains powered.
Since you're new to Arduino, start with the examples in the IDE.
You will quickly discover that it's not as hard as it seems.
Then try to write a simple sketch, and expand it to what you want it to do.
Help is always here.
Leo..

Thanks,

I don't need to control the pump, this just sorry of site there and works itself based on the volt free contacts. I can easily adjust dosing in the pump.

I have the flow sensor so will get a board and relay set and see what happens.

what is a volt free contact ?

Hi,

A volt free contact is a standard contact on a relay, there is no voltage or current on it.
You provide the current.
In other words it is completely isolated from any gnd or supply.

Tom.... :slight_smile:

poor site design strikes again,

killed my post because someone else posted while i was typing.

I really wish the moderators knew how to write code.

dave-in-nj:
poor site design strikes again,

killed my post because someone else posted while i was typing.

I really wish the moderators knew how to write code.

No problem here, using Firefox. I'm alerted when somebody else has posted while I was editing, and nothing is lost.

Perhaps you configured your browser to not allow the tab switch? Which browser do you use?

+1
Warns me when somebody else has posted just before me.
Then I can decide to post or not.
Also running Firefox here.
Leo..

Wawa:
+1
Warns me when somebody else has posted just before me.
Then I can decide to post or not.
Also running Firefox here.
Leo..

I use chrome,
typically post without incident.
in chrome you have to post before the poor settings on this site kick in and crash, only after you try to post does it show the failure and give you the warning.
I think that there is no warning in chrome when someone else posts, but only after I try to post.
the other problem is that when the post is long, the warning is not shown, but you have to scroll down to see it.
I submit that if you coded a project reading a water sensor, and the readings failed because some other thing happened in your project, that you would consider it a bug and fix it.
for me, this in the only software that does this. I do get warnings when I try to save a file with the same name in WORD and such, but that is over-writing MY work, not adding to others.
I certainly can appreciate others who have adapted to software bugs.