I compared my 2 PH meters, with interesting results
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Ive read here a few times how people wait for the wort sample to cool for either pH readings or gravity samples.
these are super handy for cooling samples in a minute or two.
The frosty mug.
these are super handy for cooling samples in a minute or two.
The frosty mug.
Does anyone have any experience using the Milwaukee PH testers; in particular the MW 101 or MW 102?
http://www.milwaukeeinstruments.com/site/component/content/article/36-standard-portable-meters/81-products-g-standard-portable-meters-g-mw102
The MW 102 was what I had originally planned to replace my Hanna 98128 with; however I caught wind of the ADWA AD12 and ran with that, considering the $62 price tag.
http://www.milwaukeeinstruments.com/site/component/content/article/36-standard-portable-meters/81-products-g-standard-portable-meters-g-mw102
The MW 102 was what I had originally planned to replace my Hanna 98128 with; however I caught wind of the ADWA AD12 and ran with that, considering the $62 price tag.
rude
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I got the AD12 was $150 perth scientific but got it through the servovendi for $62
Perth scientific didnt have the AD12 in stock so maybe thats why he was promoting the AD11
Still as far as PH meters go the AD11 or 12 are on the cheap side
Used it twice now bought storage solution & put a bit in the cap oring seals it hope thats enough
Perth scientific didnt have the AD12 in stock so maybe thats why he was promoting the AD11
Still as far as PH meters go the AD11 or 12 are on the cheap side
Used it twice now bought storage solution & put a bit in the cap oring seals it hope thats enough
Batz
Batz Brewery...Hand crafted beers from the 'Batcav
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From what I have read here PH meters are more problems than what they are worth. I have considered adding one to my brew kit on occasions but it seems not worth the trouble to me. I do have some PH test strips, these are not all that useful to me either, I'm totally colour blind.
Might just pour a beer, that I have no problems with what so ever.
:beerbang:
Might just pour a beer, that I have no problems with what so ever.
:beerbang:
Danscraftbeer
Well-Known Member
I will state on my behalf. Read the instructions properly, twice, three times if it takes that much to sink in.
Don't take your own judgment over the instructions.
Buy locally and certified so you can talk with a knowledgeable person of the suppliers. I'll name them: http://www.perthscientific.com.au/product/pocket-ph-tester/
They called me when they noticed an oversight on this order. Get two big bottles of PH4 and PH7 calibration fluid.
Don't take your own judgment over the instructions.
Buy locally and certified so you can talk with a knowledgeable person of the suppliers. I'll name them: http://www.perthscientific.com.au/product/pocket-ph-tester/
They called me when they noticed an oversight on this order. Get two big bottles of PH4 and PH7 calibration fluid.
I was going to ask also if anyone has the milwaukee MW102 . I have been looking at getting a ph meter and this is what i was leaning towards.
I have read quite a lot of good feed back around them but none from any Aussie brewers, That i have found anyway.
Price seems very reasonable and has to be better than the strips i use. Not that they have not helped i just want to be more accurate if possible.
I have read quite a lot of good feed back around them but none from any Aussie brewers, That i have found anyway.
Price seems very reasonable and has to be better than the strips i use. Not that they have not helped i just want to be more accurate if possible.
klangers
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With any instrument there is accuracy and there is precision. Two different things.
Accuracy is the deviation from the actual value.
Precision is sort of like the repeatability.
Think of a gun at a range shooting 10 round groups. The accurate AND precise weapon will have a neat little hole at the bullseye. The accurate but NOT precise weapon will have holes all over the place, with an average location on the bullseye. The inaccurate AND precise weapon will have a neat little hole somewhere else on the target other than the bullseye. As you can tell, it's better to have a precise weapon because it's more repeatable, and can be calibrated to accuracy.
Calibration will sort out accuracy, but the quality of the meter will determine precision. This is the issue here - cheap probes may be accurate but they sure aren't precise. You can calibrate until the cows come home but they will still be more of a shotgun than a rifle.
Accuracy is the deviation from the actual value.
Precision is sort of like the repeatability.
Think of a gun at a range shooting 10 round groups. The accurate AND precise weapon will have a neat little hole at the bullseye. The accurate but NOT precise weapon will have holes all over the place, with an average location on the bullseye. The inaccurate AND precise weapon will have a neat little hole somewhere else on the target other than the bullseye. As you can tell, it's better to have a precise weapon because it's more repeatable, and can be calibrated to accuracy.
Calibration will sort out accuracy, but the quality of the meter will determine precision. This is the issue here - cheap probes may be accurate but they sure aren't precise. You can calibrate until the cows come home but they will still be more of a shotgun than a rifle.
Coalminer
Well-Known Member
That was the same answer I got to my enquirymattjm said:
On 28/04/2016 12:20 PM, Perth Scientific Sales wrote:
> Hi,
> 1 When will the AD12 PH meter be back in stock - We only stock the AD11 - there is very little difference in performance. Using a pocket meter to 2-dec places is not advisable and gives a false impression of accuracy.
>
> 2 Cost of replacement electrode - AD11P electrode is $65.00+G
>
> 3 Cost of the necessary calibration and storage liquids – ph 4 and 7 in sachets (10pk) - $15.00+G for each level
>
> 4 Postage cost to Newcastle NSW - $12.00+GST
>
> Rgds,
>
> jb
>
> John Bonar
>
> GENERAL MANAGER
>
>
Responses to my questions below will hopefully look at process material itself. What if the instruments are all accurately measuring the process variable, but the process itself is not accurate enough for a measurement of that level of precision.
1: Does the pH of a mash need to be measured to a 0.01 level of precision?
2: Would the pH of a mash solution, even allowing for continuous agitation, become sufficiently uniform so that a 0.01 level of precision is an accurate measurement of the mash's average pH?
3: Does the pH of a solution homogenise rapidly, such as temperature or pressure?
4: Does the pH of a mixture of grain solids and liquid homogenise at all?
1: Does the pH of a mash need to be measured to a 0.01 level of precision?
2: Would the pH of a mash solution, even allowing for continuous agitation, become sufficiently uniform so that a 0.01 level of precision is an accurate measurement of the mash's average pH?
3: Does the pH of a solution homogenise rapidly, such as temperature or pressure?
4: Does the pH of a mixture of grain solids and liquid homogenise at all?
Killer Brew
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Wow, those things are still around?? My sister and i had them as kids in the 80's. They were awesome!Frothy1 said:
1/ No - I would be very skeptical about the reliability of pH meters that read 0.01 and cost less than $1K
2/ No - self answering from 1/. Trust readings on a good meter to 0.1 - yes
3/ Maybe - depends a bit on what you call rapidly. As the wort pH is mostly a result of water chemistry and malt acid, most of the acid comes (90%) from bacterial lactic acid on the husk it is very available so 10 minutes or so and I think it would be fairly stable.
4/ Probably - given time. I suspect homogenise might be the wrong term, stabilise would be closer. the major effects on pH aren't from the sugars that we extract from the malt but from the water, acid, other minerals in the malt (phosphates), melanoidins in dark/roast malt, all of these go into solution fairly quickly.
We are looking to work in a pH 0.4-0.5 points wide range in what is a fairly complex environment at varying temperatures. If you can get reasonably consistent readings to 0.1pH don't rely on ATC too much you should get good results and control over your brewing. Without spending the earth, and getting an ulcer stressing over things you cant really change anyway.
If you want to get a good reference pH you probably would need to titrate, can be surprisingly accurate.
Mark
2/ No - self answering from 1/. Trust readings on a good meter to 0.1 - yes
3/ Maybe - depends a bit on what you call rapidly. As the wort pH is mostly a result of water chemistry and malt acid, most of the acid comes (90%) from bacterial lactic acid on the husk it is very available so 10 minutes or so and I think it would be fairly stable.
4/ Probably - given time. I suspect homogenise might be the wrong term, stabilise would be closer. the major effects on pH aren't from the sugars that we extract from the malt but from the water, acid, other minerals in the malt (phosphates), melanoidins in dark/roast malt, all of these go into solution fairly quickly.
We are looking to work in a pH 0.4-0.5 points wide range in what is a fairly complex environment at varying temperatures. If you can get reasonably consistent readings to 0.1pH don't rely on ATC too much you should get good results and control over your brewing. Without spending the earth, and getting an ulcer stressing over things you cant really change anyway.
If you want to get a good reference pH you probably would need to titrate, can be surprisingly accurate.
Mark
Mardoo
Noob What Craps On A Bit
Urine sample bottles are perfect for taking pH readings. After you wash them out
But really, the bomb. Right width for almost all pocket meters and put into a cup of water, lid on, they cool quite quickly.
But really, the bomb. Right width for almost all pocket meters and put into a cup of water, lid on, they cool quite quickly.
I learn a lot there MHB, thank you.MHB said:
What I meant with 1/ was where you finished I think. We don't really need pH process control to 0.01 it seems. And even then, a home brewer could not control the other variables sufficiently to warrant focus on pH to that degree.
