Author Topic: pH51  (Read 1299 times)

Offline bendbrew

  • Assistant Brewer
  • ***
  • Posts: 128
    • View Profile
pH51
« on: September 20, 2010, 04:38:16 PM »
Okay, here is a possible stupid question but I purchased the Milwaukee pH51 meter.  It states to store it in a few drops of storage solution or pH7 solution in the protective cap.

Is it simply "few drops" and can I store it with few drops in its case; i.e. laying down horizontally.  Will that take the solution off the electrode?

Finally, when would you know the electrode is shot.

Bill

Offline jeffy

  • Brewmaster General
  • *******
  • Posts: 2444
  • Tampa, Fl
    • View Profile
Re: pH51
« Reply #1 on: September 20, 2010, 05:16:45 PM »
I don't have that brand of pH meter, but the instructions are similar.  I store mine upright with some 7.0 solution in the end cap.  Since I use a capful when I calibrate it's easy to save this for storage.
I think you'll know when the electrode is getting old when it takes way too long to calibrate.  Mine is a year old and recognizes the 7.0 right away, but is taking almost a minute to recognize the 4.0 solution and then longer to calibrate to it.  I think this means it's getting up there in age.
Jeff Gladish, Tampa (989.3, 175.1 Apparent Rennarian)
Homebrewing since 1990
AHA member since 1991, now a lifetime member
BJCP judge since 1995

Offline euge

  • Official Poobah of No Life.
  • *
  • Posts: 7223
  • Estilo Casero
    • View Profile
Re: pH51
« Reply #2 on: September 20, 2010, 11:48:06 PM »
I do the same, but you'll need to change the storage frequently.
The first principle is that you must not fool yourself, and you are the easiest person to fool. -Richard P. Feynman

Offline tygo

  • I spend way too much time on the AHA forum
  • ********
  • Posts: 2622
  • Sterling, VA
    • View Profile
Re: pH51
« Reply #3 on: September 21, 2010, 03:47:49 AM »
I store my pH 600 with the probe completely submersed in storage solution.  I believe that prolongs the life over using 7.0 buffer solution.
Clint
Wort Hogs

Fermenting: Wit
On Tap: Lucifer's Hammer Golden Strong Ale, Dopplebock, Old Fuzzynut's Ale

Offline bendbrew

  • Assistant Brewer
  • ***
  • Posts: 128
    • View Profile
Re: pH51
« Reply #4 on: September 21, 2010, 07:19:21 AM »
Thanks- what should I look for to see if is no longer functioning properly or dried out?  Compare it to a test strip?


Offline jeffy

  • Brewmaster General
  • *******
  • Posts: 2444
  • Tampa, Fl
    • View Profile
Re: pH51
« Reply #5 on: September 21, 2010, 07:43:53 AM »
You should calibrate it every time you're going to use it.  Get some extra 7.0 and 4.0 solutions for this.
Jeff Gladish, Tampa (989.3, 175.1 Apparent Rennarian)
Homebrewing since 1990
AHA member since 1991, now a lifetime member
BJCP judge since 1995

Offline denny

  • Administrator
  • I must live here
  • *****
  • Posts: 11660
  • Noti OR [1991.4, 287.6deg] AR
    • View Profile
    • Dennybrew
Re: pH51
« Reply #6 on: September 21, 2010, 08:37:50 AM »
you'll need to change the storage frequently.

This is something I wasn't aware of.  How frequently?  Is there some sign that it's time to change it?
Life begins at 60.....1.060, that is!

www.dennybrew.com

The best, sharpest, funniest, weirdest and most knowledgable minds in home brewing contribute on the AHA forum. - Alewyfe

Offline euge

  • Official Poobah of No Life.
  • *
  • Posts: 7223
  • Estilo Casero
    • View Profile
Re: pH51
« Reply #7 on: September 21, 2010, 10:40:26 AM »
you'll need to change the storage frequently.

This is something I wasn't aware of.  How frequently?  Is there some sign that it's time to change it?

Mine gets little wisps of gunk forming in it (similar to an infected bottle of beer) and the read will be about 6.8-6.9. The green color fades and a slime forms in the cap. Fresh solution and it reads 7.0 without re-calibrating. I think it's something from the probe contaminating it even though it is kept religiously clean.

Might not affect everyone but it's good policy to change the storage solution frequently (weekly) if you start to see a drift for no reason.

The first principle is that you must not fool yourself, and you are the easiest person to fool. -Richard P. Feynman

Offline bluesman

  • Global Moderator
  • I must live here
  • *****
  • Posts: 8678
  • Delaware
    • View Profile
Re: pH51
« Reply #8 on: September 21, 2010, 11:43:05 AM »
Here's a guide to maintaining and storing pH probes.

http://home.comcast.net/~mzapx1/FAQ/pHProbes.pdf
Ron Price

Offline johnf

  • Brewer
  • ****
  • Posts: 428
    • View Profile
Re: pH51
« Reply #9 on: October 05, 2010, 05:35:49 AM »
Thanks- what should I look for to see if is no longer functioning properly or dried out?  Compare it to a test strip?



Does the meter give you any info when it calibrates? (slope and offset)?

If not, as the electrode degrades it will take longer to recognize calibration solution. Also the calibration will not hold as long. For example a few hours into your brew day a (rinsed) probe can be used to measure fresh calibration solution and should be accurate. You can perform this exercise every few months and record the results. As the probe degrades it may measure the calibration solution inaccurately (outside of the probe's accuracy, not its resolution) and this will get worse with time.