[SOLVED] HC-SR04 and percentage value

[frenesik]

Hello,

So I add an HC-SR04 module to tell me the tank level. I want to express this value in percent example:

HC-SR04 %
7 100
40 0

Under arduino via val = map (val, 7, 40, 100, 0); I get there but through the rules I do not know how to express this value, if someone had a tutorial or a little help thank you.

I am French and translated via google translation, I hope you will understand.

[grovkillen]

You need to put a equation to your value:

Code: Select all

121-3*%value%

https://www.mathsisfun.com/equation_of_line.html

y=m*x+b

[frenesik]

Re,
I found a lua script for domoticz that does very well. THX

[grovkillen]

Good, but it's sometimes easier to just have the ESP Easy-unit report the correct value. I want to have as little intelligence on server-side as possible.

[frenesik]

Thank you to you friend, but let's say in addition it had to remove a margin of height of the sensor compared to the level of tank.

[maluko]

Re,
I found a lua script for domoticz that does very well. THX

Can you share the lua script?

thanks

[grovkillen]

Thank you to you friend, but let's say in addition it had to remove a margin of height of the sensor compared to the level of tank.

Still, easy in equations.

Example:

Code: Select all

121-3*(%value%-5)

Where "5" is the margin removed.

No need for a server in my opinion. Let's make the nodes report the correct value in the first place.

[frenesik]

Re,
I found a lua script for domoticz that does very well. THX

Can you share the lua script?

thanks

Code: Select all

-- Nom du capteur HC-SR04
depth_sensor = 'Niveau'
-- Capteur à creer nom et id à modifier
pct_sensor = 'Niveau cuve'
pct_sensor_id = 1389
-- Hauteur total moins la marge (23 - 9 = 12)
tank_height = 12

commandArray = {}

if (devicechanged[depth_sensor]) then
   --Soustraire marge du capteur
   depth = ( otherdevices_svalues[depth_sensor] - 9 )
   pct = ( tank_height - depth ) / ( tank_height / 100 )
 commandArray[1] = {['UpdateDevice'] = pct_sensor_id .. "|0|" .. pct}
end
return commandArray

[frenesik]

Thank you to you friend, but let's say in addition it had to remove a margin of height of the sensor compared to the level of tank.

Still, easy in equations.

Example:

Code: Select all

121-3*(%value%-5)

Where "5" is the margin removed.

No need for a server in my opinion. Let's make the nodes report the correct value in the first place.

Thanks to you for your perseverance lol, I tried I do not find the same values ​​compared to the script I modify the margin: x

[grovkillen]

This formula/equation in your device value would do the exact same thing:

Code: Select all

100-100/12*(%value%-9)

Or typed like this:

Code: Select all

(12+9-%value%)/12*100

Given that tank height is 12, and offset is 9.

[frenesik]

This formula/equation in your device value would do the exact same thing:

Code: Select all

100-100/12*(%value%-9)

Or typed like this:

Code: Select all

(12+9-%value%)/12*100

Given that tank height is 12, and offset is 9.

Oh a big thank you to you friend, it works niquel good I have not understood everything of the formula but it can be great when displaying on an OLED if you want to display it in% Thank you to you super your effort;)

[maluko]

carefull with the water vapor because i had this sensor with mysensors working fine but after 2 months stop give good values, it was the oxid by the water inside the sonar piece.

[gojonny@tiscali.it]

Hello, I have tried the examples you used but I can not manage, I have a water tank when the tank is full the distance is 43cm and I would like the displayed value to be 100% when the cistern is empty measuring 70cm and I would that the measure displayed was 0% I tried several rules but I have not yet succeeded, do you think since you have arrived at the solution which formula you use? thanks in advance Giovanni

[grovkillen]

If 70 = 0% and 43 = 100% you simply add this as a formula for the value:

(70-%value%)/(70-43)*100

[gojonny@tiscali.it]

perfect thanks, considering the examples above I would never have arrived !!! hello thanks again