What is the accuracy of the GHL pH Probe?

[arking_mark]

Assuming the probe is properly calibrated, what is its accuracy?

 

[Lasse]

As I know it - it is difficult to give a accuracy of a pH probe - instead are electrode slope and offset from the zero point 7 of importance.

According to Quality Certificate that follow the probes - is the electrode slope at 25 degree C > 95% of the theoretical value (of the slope) and zero offset < 20 mV

Sincerely Lasse

 

[arking_mark]

The Milwaukee MW102 claims an accuracy of 0.02:

Milwaukee MW102 PRO+ 2-in-1 pH and Temperature Meter with ATC

The MW102 is one of Milwaukee's best selling products. The meter offers remarkable accuracy, a rugged design and simple operation. Buy one today.

milwaukeeinstruments.com

Is there an equivalent for GHL +/- 0.??

 

[Lasse]

You talking about the meter - not the probe. In GHL´s case it should be the accuracy for the program in the computer and the electronics in the pH unit. I do not know this.

Sincerely Lasse

 

[Ditto]

@Vinny@GHLUSA

 

[arking_mark]

I can't find it anywhere. I know Hanna's pH meters are +/- 0.1.

 

[Vinny@GHLUSA]

Same, +/- 0.1

 

[george7523]

what is more puzzling is the fact that GHL decides to package ph7, ph4 calibration fluids with its kh director pack and profilux 4 starter pack. its instruction manual specifically states for saltwater ph7 and ph9 is required. NOT ph4. so it's supplying users with useless calibration ph4 calibration fluid and requiring them to pay an extra $8 to buy ph9 fluids. its confusing and inconvenient. they can't include all 3 fluids for the $800 you pay for the package? ridiculous !

 

[Lasse]

As I said before - all P4 starter pack I have seen content pH 4,7 and 9. The KH director does not because it should only be calibrated between 4 and 7. The titration goes down to 4.25 - therefore should the pH probe only be calibrated between 4 and 7.

Sincerely Lasse

 

[Borat]

As I said before - all P4 starter pack I have seen content pH 4,7 and 9. The KH director does not because it should only be calibrated between 4 and 7. The titration goes down to 4.25 - therefore should the pH probe only be calibrated between 4 and 7.

Sincerely Lasse

Hi Lasse,

warmest greetings from a friendly nation of Kazakistan!

I have also seen that titration test goes to PH 4.2 (e.g. Alkatronic/KH Keeper) - do you know why? I was reading Randy's DIY Alkalinity article and was under impression that titration endpoint should be between 4.4 and 4.5?

Borat.

 

[Lasse]

I may have done a mistake when I said that KH director have 4.25 as break point - I do not know for sure according to KH director - but for Alcatronic - it is 4.25. That I know for sure (I know the developer of that equipment - he is a Swede). It is based on different theories and my friend say that 4.25 is the right endpoint for saltwater.

Sincerely Lasse