Two different problems with two different pH meters (SKU: SEN0161)

userHead Account cancelled 2018-11-20 18:50:17 2391 Views1 Replies
I have two ph sensors that I'm trying to use in my masters thesis, but both doesn't work properly, both in their own way.

One ph sensor only measures ph~7, i put it in a pH 7 buffer and the value is 7, but in a pH 4 buffer it still shows ph 7. (the voltage is constant at 1.98)

The other one shows ph 5,83 in ph 7 buffer and ph 4 buffer shows ph 2.10. (Voltage 1.68 and 0.66 respectively)

Any idea how to remedy this?

I'm using an arduino Uno with an external power supply (9V 600 mA) connected to my computer which runs windows 10.
The setup and code is almost the same as in the wiki. The BNC connector is connected to the uno at 5v, gnd and A1, the only part of the code I changed is to define A1
2018-12-24 15:45:53 The probes might be broken, have you tried the new code to test them ... alibration userHeadPic robert.chen