pH Meter Calibration

[Flem]

How often do you calibrate your pH meter?
How do you know if it needs calibrating?

 

[AlFulchino]

if you use very regularly then i would check monthly...if very irregular than each time to play it safe

calibration liquid is sold for the meters....you calibrate against this...anyone who sells meters sells what you need to calibrate

 

[ibglowin]

I calibrate mine before each use. It only takes 30 seconds. The most I have seen it off is about ~0.1 pH unit and usually less than that.

 

[Runningwolf]

Good Lord I was just going to start a thread on this. PH Calibrating solution goes bad!!! I would replace this every six months. I calibrated yesterday with some older stuff I had that was a year old. I had eight wines under 3.0 raising an alarm. I just recalibrated with new solution and of the 23 wines I tested everyone was off from yesterday. Now I only have 3 wines under 3.0

When you calibrate use four shot size glasses. Two holding your 7.01 solution and two holding your 4.01 soultion. Use one of the cups to rinse off in first and then use the second one for your actual calibration.

 

[Runningwolf]

Not to hijack this thread but I have three California wines under 3.0:
Gewurztraminer 2.93
Liebfraumilch 2.85
Riesling 2.93

I do not have an acid reading at this time. I am looking for suggestions or comments as I know this is way to low.

 

[Flem]

I calibrate mine before each use. It only takes 30 seconds. The most I have seen it off is about ~0.1 pH unit and usually less than that.

Mike, didn't I read a post one time that you only calibrate using one solution?

 

[ibglowin]

Yep,

Only the 4.0 since the wines pH is always between 3.2 - 3.9. If you use 4.0 and 7.0 your basically calibrated then between those values. Your better off with a single point 4.0 since your samples is usually so close to the 4.0 anyway.

 

[robie]

Good question, Flem, I was going to ask the exact same question. It does seem logical a single point 4.01 calibration would be better than the dual, but I didn't know for sure.

Thanks

 

[grapeman]

Yep,

Only the 4.0 since the wines pH is always between 3.2 - 3.9. If you use 4.0 and 7.0 your basically calibrated then between those values. Your better off with a single point 4.0 since your samples is usually so close to the 4.0 anyway.

Unless you use your meter for doing a TA test where you go to 8.2 and then you need to calibrate using both.

 

[ibglowin]

Agree, that one would be better to have the 2 point for sure!