How to calculate volume i should pour?

I've experimented the cups, they bear the heat, and the mixer bowl is from an old coffee machine.
You haven't answered me sir about the two suggestions

aymannox:
This sensor is for 105C, I will use it for the low level and a floating sensor for high level , I will not use this transistor sensor in the tank because at the bottom I have a 220v heater tube so, i will use it in the mixer bowl because is just a plastic and it's isolated from any power source

i have an idea to put 3 level in the mixer bowl each one for one cup, for example, the valve to pour the coffee in the first cup is opened, when the liquid reaches the second level, the valve is turned off and the second cup placed under the valve ...

What do you think?

Because that depends on the question that you didn't answer after multiple times being asked... What material is that mixing bowl made of? That's essential for what sensors can work at all.

If big enough float switches of course can work - provided they can stand the heat - but is it big enough to have sufficient level change for a single cup output? And is the method even accurate enough?

I will use the transistor sensor in the bowl mixer and the floating sensor for the tank
For the mixer bowl like I say, I will use 3 level each one for one cup and the mixer is isolated, it's just a plastic bowl not connected any source of power, so there will be no problem if i merge the 5v in water when it's poured ?

Depends on what else touches that water. Such as the solenoid that releases it. Nonetheless it's poor practice and it's dead easy to invert the circuit.

wvmarle:
Depends on what else touches that water. Such as the solenoid that releases it.

It does not touch anything, as I say it just a plastic bowl and i found in some old coffee have a plastic stopper in the bottom of the bowl, so why you put the decanter, it pushes the plastic stopper to let the coffee pass.
My idea is putting a solenoid to push the stopper, so it's isolated and i can use the transistor sensor with the 3 levels?


NB: The solenoid is far from the dispensing tube

wvmarle:
onetheless it's poor practice and it's dead easy to invert the circuit.

I haven't understood, Sir.

Invert the circuit. Make it react to a connection to GND instead of a connection to +5V. Pretty easy to do with PNP transistors.

You're in for some serious headaches with such a shaped bowl, as the water level drop will be quite small for the first cup, much more for the second and even more for the third.

Anyway did you even build anything? Because you'll have to start building. Find out how much water level drop there is for one, two, three cups. That it all fits. How do you get the correct volume in the mixing bowl in the first place? You won't be always making three cups. Very often only one, or maybe two.

Like this

wvmarle:
How do you get the correct volume in the mixing bowl in the first place? You won't be always making three cups. Very often only one, or maybe two.

If I want 2 cups for example, the pump start delivering the water to the bowl when it reaches the second probes of the transistor sensor, The pump stops

Something like that.
You still will run into the problem of electrolyses - increase the base resistor size, 100k or even more should be able to give a reliable signal while having very little current running through the liquid, limiting the problem. Instead of the LEDs use a 10k resistor. And of course use a non-toxic material for the probes.

I will remove the led and connect the wires to the Arduino

You need a pull-down resistor or your pin is floating. So can't just remove that LED & resistor.

wvmarle:
use a non-toxic material for the probes.

Which metal I can use it for the probes?

Hi,
I have a Seaco Coffee Pod machine and it DOES NOT use a timer, it uses a flow meter.
How do I know, different brands/contents of the pods affects the flow of hot water, yet it dispenses the same amount of water, it just takes longer or shorter time to dispense.

Check this link.

https://espressodolce.ca/product/saeco-parts-286473300-flow-meter-sensor-assembly/

Tom... :slight_smile:

25$ is too expensive for me, I will use the transistor sensor to detect the volume needed

wvmarle:
Something like that.
You still will run into the problem of electrolyses - increase the base resistor size, 100k or even more should be able to give a reliable signal while having very little current running through the liquid, limiting the problem. Instead of the LEDs use a 10k resistor. And of course use a non-toxic material for the probes.

Like that ?

Which metal is good to use it in probes?

This puts 12V on your Arduino pin - battery should be 5V. And as said before: any non-toxic metal, e.g. SS304.

To avoid powering the circuit by the Arduino, will use an optocoupler, what do you think?

I don't see the use of this. Reducing the voltage is much better (also for the probes themselves).

wvmarle:
I don't see the use of this. Reducing the voltage is much better (also for the probes themselves).

Ok, I will use 5v to power the circuit, I used the optocoupler just to isolate the circuit from the Arduino