+ Reply to Thread
Results 1 to 3 of 3

Thread: Digital Chlorine Meter

  1. #1
    pratzert is offline Lifetime Member Thread Analyst pratzert 0
    Join Date
    Dec 1969
    Location
    .
    Posts
    58

    Default Digital Chlorine Meter

    Hi All.

    I use a digital pH meter and it seems to do a decent job.

    I have also seen a few Digital Chlorine meters on the web.

    Has anyone (BEN?) used one of them? Any good?

    I'd like to hear some opinions/comments on them.

    Thanks !

  2. #2
    PoolDoc's Avatar
    PoolDoc is offline Administrator Quark Inspector PoolDoc 5 stars PoolDoc 5 stars PoolDoc 5 stars PoolDoc 5 stars PoolDoc 5 stars PoolDoc 5 stars PoolDoc 5 stars
    Join Date
    Jan 2005
    Location
    Georgia
    Posts
    11,386

    Default Re: Digital Chlorine Meter

    Every portable digital 'chlorine meter' I've seen is EITHER totally bogus (units under $20) OR based on ORP electrodes.

    Your pH meter actually measure pH, but ORP meters do NOT actually measure chlorine. Instead they measure the NET oxidizing state of the water. That is, they measure all the oxidizers minus all the reducing agents.

    This means:
    • If you add dichlor (50% chlorine, 50% stabilizer) your ORP may go DOWN, even though the chlorine went UP.
    • If you add potassium monopersulfate, your ORP, or indicated chlorine, will go UP, even though there's none in the pool!
    • If you have stabilizer AND chlorine in the pool, and the sun gets covered by clouds, your indicated chlorine will increase.
    • And more . . .

    I have sold and serviced multi-thousand dollar OPR/pH control systems for commercial pools. They can work well on indoor pools. They tend to be a nightmare on outdoor pools, unless you have a staff pool person
    (a) who will listen,
    (b) has some basic knowledge of science and chemistry, and
    (c) has an IQ > 110.
    Most pools lack this sort of staff . . . which is why I've found perfectly good $10,000 Stranco pool controllers turned off.

    But, there's a market for chlorine meters. And where there's a market, SOMEBODY will sell SOMETHING!
    There are some claimed 'true' chlorine electrodes, like this Orion Scientific unit:
    Orion 9770BNWP Residual Chlorine Ion Selective Electrode . . . for $666.
    But I've never had a reason to test one, and I've never seen reliable information on whether they really work, without endless calibration!

    So . . . save your money.

  3. #3
    pratzert is offline Lifetime Member Thread Analyst pratzert 0
    Join Date
    Dec 1969
    Location
    .
    Posts
    58

    Default Re: Digital Chlorine Meter

    Thanks Ben.

    Sounds like I should save my money and stick with the wet agent for testing/measuring free chlorine.

    I appreciate the advice.

+ Reply to Thread

Similar Threads

  1. Do You Need a pH Meter to Test Pool pH?
    By PoolDoc in forum Testing and Adjusting Pool Water Chemistry
    Replies: 5
    Last Post: 05-31-2018, 04:05 PM
  2. TDS meter.
    By wwmcintyre in forum --cleanup--
    Replies: 0
    Last Post: 06-14-2017, 10:51 AM
  3. Flow meter power control (solar heater risk mitigation)
    By pgiering in forum In-Ground Pool Construction and Repair
    Replies: 0
    Last Post: 07-30-2012, 02:21 PM
  4. cast iron vs. plastic headers in heater, digital vs. non-digital
    By vinouspleasure in forum Pool Equipment & Operations
    Replies: 2
    Last Post: 05-08-2011, 05:49 PM
  5. ph & chlorine test meter -can someone help me to calibrate it
    By sflaster in forum Testing and Adjusting Pool Water Chemistry
    Replies: 3
    Last Post: 07-18-2006, 05:02 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts