homemade automatic KH Tester With Opensource.

[axlzys]

far enough,
there is another way that you can use anoher motors interface,but you need change the code.change to motor 4,
and find the file Tester.py in folder APP, change every 'kit.motor3.throttle' to'kit.motor4.throttle' except line 43 kit.motor3.throttle = 0, after that the dosing pump will disable.

 

[tungvuu]

I don't know anything about coding, so I'm afraid to edit the code. Now I use a DC-DC boost converter to increase the voltage from 3.7V to 11.2V for the acid pump to work (with 3.7V of course, the acid pump cannot run, although the other 3 pumps still receive full 12V). The device could not increase to 12V because the voltage from the HAT Motor was too low, but with 11.2V the acid pump worked perfectly.
I also use another circuit to lower the voltage from 3V to 1.5V for the stirring motor because with 3V it rotates too fast.
Currently when I Calibration Reagent, the acid pump drops 100 drops perfectly, but when Calibration Titration, the KH pump doesn't run for 10 seconds but the acid pump drops exactly 1 drop and then stops. It's weird, because when I click open and close all 4 pumps work properly.

 

[axlzys]

I don't know anything about coding, so I'm afraid to edit the code. Now I use a DC-DC boost converter to increase the voltage from 3.7V to 11.2V for the acid pump to work (with 3.7V of course, the acid pump cannot run, although the other 3 pumps still receive full 12V). The device could not increase to 12V because the voltage from the HAT Motor was too low, but with 11.2V the acid pump worked perfectly.
I also use another circuit to lower the voltage from 3V to 1.5V for the stirring motor because with 3V it rotates too fast.
Currently when I Calibration Reagent, the acid pump drops 100 drops perfectly, but when Calibration Titration, the KH pump doesn't run for 10 seconds but the acid pump drops exactly 1 drop and then stops. It's weird, because when I click open and close all 4 pumps work properly.

that is right.because the code of Titration is wrong.i have no time to fix it.after calibration your can try your first test.

 

[tungvuu]

Please help me, how long does it take to calibrate the pH probe, I put the probe in both 4.0 solution and then 7.0 solution, after a long time still no message, come back to the main screen with 4.0 solution , the line is only around 3.2, with 7.0 it gradually increased and stopped at 6.2. I have tried swapping another probe and it still shows the same value, still no successful calibration message.

 

[axlzys]

Please help me, how long does it take to calibrate the pH probe, I put the probe in both 4.0 solution and then 7.0 solution, after a long time still no message, come back to the main screen with 4.0 solution , the line is only around 3.2, with 7.0 it gradually increased and stopped at 6.2. I have tried swapping another probe and it still shows the same value, still no successful calibration message.

if the calibration is success,the web will show you message immediately.
put the probe in the solution.see the main page, until the value is stable,then go to the settings page and click the button calibrate ph.

 

[insidethesquare]

Amazing project. Just bought the parts. I understands where the tubes go for everything but the calibration pump. Not really sure where its tubes go and what its function is. Can you pleae clarify. Thanks

 

[insidethesquare]

hello everyone,
I made a KH tester machine at home.Control with Raspberry Pi.
For the benefit of aquarists around the world, I decided to open source it.
I upload all details to the github.com, here it is : https://github.com/axlzys/KH-Tester

The case made by 3D Print,
The print time of main body and front cover are more than 10 hours, you may need a encloses naturally 3D printer.

About test accuracy:The test accuracy is 0.1dkh,and with 2 month tested,it has 0.1-0.3 difference from Hanna.

If you have any questions. Please tell me.

Here is some pics of this DIY

Amazing project. Just bought the parts. I understands where the tubes go for everything but the calibration pump. Not really sure where its tubes go and what its function is. Can you pleae clarify. Thanks

 

[axlzys]

calibration pump？did you mean the 3rd pump(titration pump) or just why should calibration the pump?
if you mean the 3rd pump,It was originally designed as a dosing pump.
if you mean why should calibration the pump,The flow rate of each DC titration pump is a little different.

 

[axlzys]

Amazing project. Just bought the parts. I understands where the tubes go for everything but the calibration pump. Not really sure where its tubes go and what its function is. Can you pleae clarify. Thanks

calibration pump？did you mean the 3rd pump(titration pump) or just why should calibration the pump?
if you mean the 3rd pump,It was originally designed as a dosing pump.
if you mean why should calibration the pump,The flow rate of each DC titration pump is a little different.

 

[insidethesquare]

Sorry I should explain it better.

The top most pump looks like it is for bringing tank water into the reaction chamber, the second pump is for pulling water out of the reaction chamber and the lowest pump is for dosing the acid. I do not understand what the other pump is for or where it is plumbed. Sorry if this is a silly question.

Thank you

 

[insidethesquare]

Sorry I think I have got it. The third pump is to dose alkalinity based on the result of the test. So it is a tester and doser together. Is this correct? If so this is even more awesome than I thought. You should change the name to KH tester and doser.

 

[Krheigh]

been using this for almost a year now... but still got one question... if i set it to do a test every 24 hour when does it do the test? would be nice to be able to determine when it should do the test.

 

[insidethesquare]

Hi guys. I built this. Just waiting to get some acid (never thought I would say that sentence ). I had a question regarding calibration. Do you calibrate the reactor chamber volume with a ph probe in. Obvious this would change the overall volume due to displacement.

Also, when calculating the water volume, why not draw the volume in the chamber into a syringe rather than use the difference in weight of the chamber with and without water.

Thanks in advance

 

[SHARK_2]

Hi axlzys,

Thanks for sharing your project. Inspired by Your work, I decided that I would try to make it too. Of course, I had to change it a bit, to suit me

My version is based on RPi Zero 2W. I also changed the pumps to peristaltic ones based on stepper motor, and since the tangle of cables started to bother me, I decided to make a dedicated PCB. The above forced me to make some changes to the code too. Of course, I also had to design the casing from scratch.

I'm currently waiting for it to print. Below are some photos of my version

 

[axlzys]

Hi guys. I built this. Just waiting to get some acid (never thought I would say that sentence ). I had a question regarding calibration. Do you calibrate the reactor chamber volume with a ph probe in. Obvious this would change the overall volume due to displacement.

Also, when calculating the water volume, why not draw the volume in the chamber into a syringe rather than use the difference in weight of the chamber with and without water.

Thanks in advance

hi when i calibrate the chamber i put the probe in.
and in fact i think use a syringe to calibrate chamber is also ok.

 

[axlzys]

Hi axlzys,

Thanks for sharing your project. Inspired by Your work, I decided that I would try to make it too. Of course, I had to change it a bit, to suit me

My version is based on RPi Zero 2W. I also changed the pumps to peristaltic ones based on stepper motor, and since the tangle of cables started to bother me, I decided to make a dedicated PCB. The above forced me to make some changes to the code too. Of course, I also had to design the casing from scratch.

I'm currently waiting for it to print. Below are some photos of my version

wow.Im very happy to see that you have done secondary development on this project.
to be honest i know nothing about PCB.So I had to use a lot of wires.the new place of water level switch is nice.Stepper motors make results more accurate.in fact At first I also planned to use a stepper motor,but The motor driver board I use can only drive 2 DC motors after using 1 stepper motor,so i gave up.
may i ask after you changed does the reaction chamber have a cover?because i find the open chamber is not good.dust bugs will in it.

 

[SHARK_2]

wow.Im very happy to see that you have done secondary development on this project.
to be honest i know nothing about PCB.So I had to use a lot of wires.the new place of water level switch is nice.Stepper motors make results more accurate.in fact At first I also planned to use a stepper motor,but The motor driver board I use can only drive 2 DC motors after using 1 stepper motor,so i gave up.
may i ask after you changed does the reaction chamber have a cover?because i find the open chamber is not good.dust bugs will in it.

Yes TB6612 can drive 2 DC or 1 Stepper, that why I used 4 of them.

I'm going to use glass reaction chamber instead printed one.

Something like this:

 

[axlzys]

I'm going to use glass reaction chamber instead printed one.

Something like this:

i think its not good, you can design a chamber that the water outlet is below.so the water can be completely drained.like kh guard.

 

[SHARK_2]

i think its not good, you can design a chamber that the water outlet is below.so the water can be completely drained.like kh guard.

I will give it a try (like in Reef Factory KH Keeper Plus)
Change it in the future is not a big deal.

 

[axlzys]

I will give it a try (like in Reef Factory KH Keeper Plus)
Change it in the future is not a big deal.

haha I wish you success