pH meter recommendations

[AzzA68]

I'm just about to order this ^

which buffer solution should I get for it? there are three options:

pH4.0
pH 7.0
pH 10

cheers

It depends what you're measuring with it.

If it's for checking water for mashing, it's going to depend on where your water is derived from. depending on who you read you're targeting around 5pH to 6pH to mash with, but if you're on municipal water your starting point could be 6.5pH to 8.5pH (depending on mineral content and how the council dose it, etc)

In short... you should calibrate for the range you're going to be reading within.

Meters are capable of 1, 2, and/or 3 point calibrations. (FIND OUT WHAT YOUR METER IS CAPABLE OF.)

1 point calibration: the buffer needs to be as near as possible to the expected pH value.

2 point calibration: the buffer set needs to bracket, or bookend, the pH values expected to be read.

3 point calibrations: the buffer set also needs to bracket the expected range with a centre point for best linearity. These are for a wide range of expected readings, or when you're going to be pH adjusting from a base to an acid, or visa versa.

Always RTFM; a meter might be able to use a 3 buffer set but it might also be able to accept a 2 or 1 point calibration also... the setting will be obscured in what buttons are pressed and when/how.

Almost all meters will do a 2 point calibration: usually 7 and either 10 or 4.

The electrodes/probes themselves are not linear, hence the need to calibrate for both ends of the expected measuring range, above and below... or not too far outside, if you must... it's the electrochemical nature of the half cell used.


If you want your electrodes to last, I do suggest buying some "storage solution" and using it to keep your probe hydrated and always ready for use.

AND... be very careful with your electrodes; they're very fragile!
A glass sphere, the "pH glass", is so thin that H+ ions can move across it. This glass must be kept clean and hydrated.
There's also a liquid junction that allows the outflow of the reference electrolyte. This junction must be kept clean and hydrated. (It's also why samples/specimens are taken from the donor/wort/water/wine but not returned.)

Read all the material on the manufacturer websites, not just the one you buy from; there's lots to know/forget about pH.
It's very critical that your readings are accurate and precise; the quality and consistency of your product depends on it!

HTH (and I didn't make too amny typos)

Cheers,
AzzA

 

[AzzA68]

Oh... and always buy a probe that has a junction suitable for the purpose you're going to use it for... consult the manufacturer for more advice on this, especially is you're making wine!

Making wine? Get the right electrode and get the right cleaning solution (with enzymes etc).

Measuring drinking/potable water? Basic electrodes with standard junctions are fine BTW.

 

[droid]

cool, thanks for the response :beer:

 

[Mardoo]

AzzA68, any recommendations on a low-end - but good quality - bench pH meter, or a top-notch handheld? I've been looking at this one.

https://www.ebay.com.au/itm/361288124308

I'd like to keep it to about $400 if possible, but am looking for something that will expand with me if I get myself into a place of professional production.

BTW, do your recommendations regarding probe and winemaking extend to mead and very high gravity beers?

 

[AzzA68]

AzzA68, any recommendations on a low-end - but good quality - bench pH meter, or a top-notch handheld? I've been looking at this one.

https://www.ebay.com.au/itm/361288124308

I'd like to keep it to about $400 if possible, but am looking for something that will expand with me if I get myself into a place of professional production.

BTW, do your recommendations regarding probe and winemaking extend to mead and very high gravity beers?

Re: the HANNA INSTRUMENTS - HI-207 - PH METER, BENCH

from eBay... a good meter no doubt. But be advised it does use a combination electrode & thermometer, which means more expense and less options when it comes time to renew it, Which the time will come. In most cases you're better off with meter that has a separate pH electrode and separate temp' probe. Temp compensation doesn't shift much in most cases, but it is beneficial. A discrete temp probe will almost never wear out, mishap or abuse are practically the only exceptions.

Try looking for "Portable pH/mV Meter - HI8424", it's a good budget conscious item with industry in mind.
http://hannainst.com/products/portable-meters/ph/portable-ph-mv-meter-hi8424.html
Be mindful that's US pricing, at US$315

RS Stock No.518-4967
http://au.rs-online.com/web/p/ph-water-analysis-meters/5184967/
Hanna Instruments HI 83141 pH & Water Analysis Meter, 0 → +14 pH

$456.75
Price (ex. GST) Each



http://hannainst.com/products/portable-meters/ph/ph-specific-features/probe-connection---bnc.html
Pick of the bunch is the HI9125; its predecessor was bulletproof and near on ham-fisted *****-proof.

When buying from places like RS, be aware of old-stock; as mentioned before the electrodes have a limited shelf life.

It also appears that Hanna have shrunk the range and updated the handhelds too. The older waterproof pH meters where "through hole" PCB's which made them easily repairable but costly to produce it today's World. If you can find an older model, working, and cheap: buy it! Just get a new pH electrode.

 

[Mardoo]

Thanks mate.

 

[AzzA68]

Thanks mate.

If looking at other models and makes/brands: look for pH electrode connection that are of the "BNC" type; it's the industry standard and allows any normal/standard type pH electrode to be used (non-amplified and without built in temp' comp, etc).

 

[Glomp]

Hi.

I have been reading posts and scouring the internet to get a ph meter.

I finally decided on the Testo.

I have seen this brand's digital thermometers and they are the M1 tank of thermometers. Where I work they are not used as a scientific instrument but more something that a carpenter would use a hammer on. They are bloody tough and work well and have probably been bought in their hundreds at Don is Good.

Features for the pH meter are:

• 1, 2 or 3 point calibration possible
• Accuracy (absolute) ±0.02 pH
• Resolution 0.01 pH
• Maintenance-free gel electrolyte
• TopSafe: Robust, water-tight, hygienic and dishwasher-proof protection case (IP68)

I got the $20 ebay rebate off the price and ended up paying $141.63 delivered.

http://www.ebay.com.au/itm/232029658713

 

[Glomp]

Just received the pH meter from Hong Kong delivered by DHL and not aussie post. Looking into its background Testo is a German company with 250M Euro worth of sale.

The meter looks great and the electrolyte gel is in the bracket/belt holder supplied so no need for storage solutions. Also how geeky is that to have a ph meter belt holder?

Everything about it looks good. You can get replacement probes but probably just as cheap to buy a new meter.

Anyway it looks the goods and may suit someone a bit wary of cheaper meters.

 

[mstrelan]

If you find a working waterproof Hanna meter in a bargain sale, buy it! (They're practically bullet proof.)

Anyone want to go halves of this 2-pack? Would come in at about $80 AUD each delivered with $10 off coupon.

Hanna GroChek pHEP 5 pH and Temperature Tester Meter Waterproof HI98128 (2 Pack)

 

[Liam_snorkel]

bugger, I would but have just ordered one of these

 

[HaveFun]

Which one is the right one for a home brewer? Testo for $140 or the Hanna one for $ 90?

https://www.ebay.com.au/itm/Testo-2...m51f8c35d9d:g:QCMAAOSwZjNbbXoL&frcectupt=true

or the Hanna one

https://www.ebay.com.au/itm/Hanna-HI98100-pH-Checker-0-01-Resolution/333147656492

Any suggestions

Cheers
Stefan

 

[markp]

Which one is the right one for a home brewer? Testo for $140 or the Hanna one for $ 90?

https://www.ebay.com.au/itm/Testo-2...m51f8c35d9d:g:QCMAAOSwZjNbbXoL&frcectupt=true

or the Hanna one

https://www.ebay.com.au/itm/Hanna-HI98100-pH-Checker-0-01-Resolution/333147656492

Any suggestions

Cheers
Stefan

Look at a horiba laqua twin ph22, only need to use small samples from a pippett dropper so it’s easy to cool quickly.

 

[razz]

I use the Horiba Laqua 22. Easy to use, I don’t use it much and I keep some drops of 7.0 on it each month to keep it from drying out. Very fast to calibrate with calibration fluids (included)

 

[FarsideOfCrazy]

The Hanna one that you posted doesn't have the greatest accuracy, +-.2, if you want that kind of accuracy you might as well get the KL one. The testo model has an accuracy of +-.02. That's more like the accuracy you'll need. No point having a PH meter that is potentially reading .2 higher or lower than what you're aiming for. Eg. your aiming for a mash PH of 5.4 and your meter reads 5.6 or 5.2, you're not even close. You might as well just use whatever BS or Bruin water says.

I've got the Horiba Laqua 22 and it is a great ph meter. I've checked it against my mates $1000 hanna meter and it was only .02 difference in the reading between the two, even he was impressed because it cooled the small sample so quickly.