Water cooling flow sensor with Duet

[fma]

I recently ordered this sensor:

https://fr.aliexpress.com/item/5-24V-USN-HS06PA-1-6mm-Hose-Barb-End-Hall-Water-flow-Sensor-Turbine-Flow-Meter/754933581.html

I chose this one, because it can handle very small flow (I guess you use a water-cooled hotend too?).

I didn't test it yet, and didn't really know how to use it; thanks for the tip using fan RPM input!

[zerspaner_gerd]

Thanks @JoergS5,

I imagined something like this:
https://www.caseking.de/bitspower-durchflusssensor-1-4-zoll-shiny-silver-waad-326.html#tech_specs
https://www.aquatuning.de/wasserkuehlung/ueberwachung/sensor-durchfluss/16247/alphacool-fliessanzeiger-g1/4-mit-tachosignal-plexi?c=385

Unfortunately, little information available.

@fma said in Water cooling flow sensor with Duet:

I guess you use a water-cooled hotend too?

Yes that's right.

So now I've looked through Wiki:

• I can not see now, to which pin I would have to plug the signal cable (V_FAN or FAN)
• To configure the External Trigger. How does this have to look like that it is triggered at a signal input of RPM 0.
  M106 P2 I1
M581 P22 S? C2

[JoergS5]

@zerspaner_gerd your sensors look nice, but I would check that someone has already written a blog about how to connect it to arduino at least. Some vendors sell sensors where you have to pay much for the data cable or software to access the data.

Edit: your first one looks pretty nice. I checked, it uses a 3 wire signal cable, should be a common setup.

You could check how the filament sensor is implemented to see which ports are possible, also. This sensor is implemented as M591, maybe a watercooling sensor can be implemented in firmware also.

[dc42]

@zerspaner_gerd said in Water cooling flow sensor with Duet:

@dc42
Unfortunately, I find nothing about the RPM monitoring, Can you share a link so I can read.

I've added some text about RPM monitoring to the page on connecting and configuring fans.

[zerspaner_gerd]

Thank you very much @dc42, that helps a lot.

The Flow Sensor has only 3 cables (GND, VIN, signal), do I need any invert PWM of fan?

And how can I read out the PIN PB6 so that a trigger is triggered at PWM 0?

I could not find a PIN number here either.
https://duet3d.dozuki.com/Wiki/Using_servos_and_controlling_unused_IO_pins

I understand that correctly, to leave the permanently connected I need a signal diode.

[dc42]

You don't need to configure a pin number, because pin PB6 is pre-configured for a fan RPM sensor. If the flow sensor uses greater than 3.3V power, use a diode between its output and PB6.

[zerspaner_gerd]

@dc42
And how can I imagine monitoring?

Would be at a loss how I should implement that.

I have to create a reaction somewhere.

[zerspaner_gerd]

Hello @dc42 ,

How can I work with the RPM signal.
It will now be displayed in DWC.

Now I need a way somehow trigger a Macro.

[dc42]

Currently the firmware does not have any facility for taking an action based on the RPM reading.

[fma]

It should be easy to build one, using an integrator (simple capacitor?) and a trigger, sending the signal on an unused endstop, which can in turn activate a macro...

[zerspaner_gerd]

@dc42,
Okay then I know that.
Thanks

@fma said in Water cooling flow sensor with Duet:

It should be easy to build one, using an integrator (simple capacitor?) and a trigger, sending the signal on an unused endstop, which can in turn activate a macro...

That sounds good but I have no idea how to build something like that.

[fma]

In fact, a board based on a 555 is even better:

https://www.qwant.com/?q=555 missing pulse detector

David, is it possible to connect the output of the 555 to the endstop input, if the 555 is powered with 3.3V (using a TLC555)?

[dc42]

@fma said in Water cooling flow sensor with Duet:

In fact, a board based on a 555 is even better:

https://www.qwant.com/?q=555 missing pulse detector

David, is it possible to connect the output of the 555 to the endstop input, if the 555 is powered with 3.3V (using a TLC555)?

Yes, that should work.

[fma]

Thanks! I'm going to make a prototype...