[Help] Setting 25mm Ultrasonic Mist Maker

[kidlat14]

Good day,

I need help. I'm working on a simple project to control an ultrasonic mist maker using an Arduino Uno. But for the life of me, I can't make it work. I attached a photo and schematics of my setup and the code.

int relayPin = 7;


void setup() 
{
  pinMode(relayPin, OUTPUT);  

void loop() 
{
  digitalWrite(relayPin, HIGH); 
  delay(5000);                
  digitalWrite(relayPin, LOW);  
  delay(5000);                
}

Thank you.

[jim-p]

@kidlat14

I can't make it work.

Is it a 5V relay?
Is it attached to pin 7 and GND?

Post the data sheet for the relay

[kidlat14]

Yes on both.

[kidlat14]

This is the specs of the relay

Relay Module 5V 10A 1 Channel with Optocoupler

Relay version: 5V
Quiescent current: 5mA
Maximum current: 50mA
Trigger current: 2-4mA


DC +: then the power supply positive (voltage according to the relay requirements, with 5V; 2, DC-: connected to the power supply negative;
IN1: 1 signal trigger side, you can set the high or low-level control relay pull; 1, NO1: 1 relay normally-open interface; 2, COM1: 1 relay common interface;
NC1: 1 relay normally closed interface

[jim-p]

Well now we need to do some debugging.

1. Does the mister work when you connect it directly to the 12V?

Reconnect the mister to the relay.

2. Disconnect the relay signal IN from pin 7 and connect it directly to 5V.
   Does therelay click and mister work?

3. Connnnect the relay signal IN to GND
   Does the relay click and mister work

[kidlat14]

1. It does not. However, when I use the 12V power supply to power other components they do work. I have four mist makers and all of them does not work when connected directly to the 12V power supply. Am I missing something here?

[jim-p]

@kidlat14

Am I missing something here?

Maybe. I think you may need aditional circuitry for your mist maker. Do you have a datasheet or a link to a website for it?

[jim-p]

From you picture, I think all you have is the transducer. You will need a drive circuit for it.

[kidlat14]

81205.pdf

Here's a link to the mist maker's specs. Can you elaborate more about the transducer and a drive circuit? I'm a newbie when it comes to electronic circuitry.

[jim-p]

The part you have is just the transducer. It's the part that vibrates at high frequencies and makes the water turn to mist. However it does not vibrate by itself. It requires some additional circuits (a driver circuit) that will make it vibrate.

[kidlat14]

Got it. I think this is what you mean.

[jim-p]

Yes exactly. The transducer and driver board are usually sold together. I looked for the driver board by itself but could not find one.

[kidlat14]

I actually have one of that board. However, it is for a smaller 5V transducer. I tried connecting the 25mm/12V transducer but to no avail.

[kidlat14]

Thank you so much for your help. May I ask some more please?

Please refer to the photos. The board is powered using micro-USB which is 5V. However, it has two 'power supply' pins that I can solder to. Can I solder my 12V power supply into it so that it can provide adequate power to the bigger mist maker?

[kidlat14]

Here is a closer look at the board

[jim-p]

It may not just be a mater of voltage but also frequency. The transducer you have is designed for 1.65MHz, the board you have may be for something different.
I would not connect 12V unless you have instructions for that board that tell you you can.

Actually, the correct driver board will probably generate a voltage much higher than 12V, maybe even as high 40V in order to drive that transducer.

[kidlat14]

Thank you so much. I've learned a lot. The first being I f-ed up by buying a transducer without a driver board. Now I'm stuck with this and have to figure it out how to make it work.

[jim-p]

1. Search for a 1.65MHz driver board capable of providing maybe 20W but must be less than 30W
2. Build a circuit from scratch Here is a schematic
   
   

[kidlat14]

Thank you so much!

[jim-p]

Here is a pdf
m165d25 driver.pdf (13.2 KB)