interface 1130

Technical Discussions on any InterfaceKits
max.tisc
Fresh meat
Posts: 3
Joined: Thu May 18, 2017 9:03 am
Contact:

interface 1130

Postby max.tisc » Mon May 29, 2017 3:05 pm

Hello
I have a problem with the formula for calculating Ph
PH = 7 - (2.5 - SensorValue / 200) / (0.257179 + 0.000941468 * Temperature)
I interfaced the 1130 with arduino having a 0-5v input, and from what I saw the 1130 has a 0-5v output, so they are perfectly compatible.
In formula, the value "SensorValue / 200" I replaced it with the arduino reading value (0-5v) and the temperature = 25 but the values returned have values from -1.90 to 15.92 ph and not 0-14ph , These values are also confirmed by calculating with the calculator.
Is the formula correct? If it is correct what is the reason for that?
Am I mistaken a few steps?
I hope to have been clear
thank you

User avatar
Patrick
Lead Developer
Posts: 3078
Joined: Mon Jun 20, 2005 8:46 am
Location: Canada
Contact:

Re: interface 1130

Postby Patrick » Mon May 29, 2017 3:26 pm

The valid output range of 1130 has some play at either end to deal with calibration, temperature compensation, etc. which can push the valid range up or down a bit

-Patrick


Return to “InterfaceKits”

Who is online

Users browsing this forum: No registered users and 0 guests