Hanna TDS meter calibration questions

Exactly, so if you are running a meter on the Hanna scale and my meter was designed to use the Truncheon scale we have to find a way to normalize our values so we are talking apples to apples. We can do that by always reporting values in EC or by somehow communicating the conversion factor of our respective meters.

I guess I don't follow. I thought that if my meter told me that my solution had 1000 ppm, then it had 1000 ppm (within accuracy tolerances). If I used my micrometer to measure the thickness of a item and if I told you the thickness in millionths of an inch, than if you measured it with your micrometer, it should be the same. I shouldn't have to tell you that my micrometer is a Starett, only that the measurement is whatever.
 
I understand, it is confusing. I had this discussion at the hydro shop and everyone, including the customers in the store and the staff had different pictures about how this works. It is a mess, although at least we have conversion factors to help us normalize the values. So I would not need to know your meter manufacturer, just your conversion factor as illustrated in post #19 above.
 
I'm not saying that I'm confused with ec/tds/ppm conversion, I'm saying that I'm confused with your rationale. If I am using the conversion factor appropriate for my meter, then when I see a ppm value on the meter, that is the approximate ppm of the solution! If I tell you what my ppm is, you don't need to know a conversion factor or anything else. The meter does all of the work!
 
I'm sorry hogdady but you are still missing something. This is just like temperature. If we both go outside, in the same location, on a day where the temperature has just dipped to freezing and we measure the temperature we will get vastly different results, even though both of our thermometers were just calibrated. You will get a reading of 32 degrees and I will get a reading of 0 degrees. This is possible because just like the TDS meters there are different ways to calculate temperature - different linear scales: centigrade and fahrenheit. So you must report 32 degrees fahrenheit for the value to be meaningful.

Likewise when measuring TDS we have the same problem. When someone reports a ppm value one has to know whether they are talking about Hanna, Eutech or Truncheon scales.

Personally I think we should all switch over to reporting TDS values in EC. That way there is no ambiguity. I hope this helps. If not you can go here to learn more. I wish I had known about this link before I opened this thread =)
 
Slimm, I gotta take my hat off to ya. Not many people would have the patience nor intellect that you have shown in discussing this topic with me. I see exactly what you are saying, and that is essentually that ppm values are bogus. If there are different conversion factors then the same ec could be converted to different ppm values, based on the meter manufactures choice. Thanks Slimm, you have opened my eyes!
:welldone:
 
okay, correct me if i am wrong but when you calibrate the meter, either by the factory setting which has the conversion factor encoded on a chip then they have to find a STANDARDIZED SOLUTION...that is where it becomes apples to apples...you cannot use say a bottle of Hanna 1413 microsiemens/cm NACl to calibrate an Oakton Ultra basic which uses a different standard of calibration solution...which is a 1400 ppm solution, in other words, what they program into the damn things does not make a diff, it is when it is calibrated and what it is calibrated to that brings everyones ppm's to where you can consistently look at a nute program and take for instance Technafloras Recipe for success....the bloom mix comes up to ~1400...not 1400 on a hanna but 1200 on a bluelab or whatever....okay? correct me if i am wrong and i will send back my degree.
 
I had a problem with this concept as well. EC is the constant. All TDS meters convert EC to PPM's by their own conversion factor.

PPM-EC-C4.jpg


So the PPM values are only comparable if you know the conversion factors of the meters in use. This is why it is important to discuss TDS values in EC rather than PPM. The thread below is an excellent read...


What is the difference between ppm and EC?

:smokin:
 
okay, i definitely understand what you are saying, but when i bought some genhydro cal solution before, this same thing was replayed, like someone else posted, in the hydro shop with fifty diff opinions...i called Oakton and they said that IF you use their calibration solution, then your ppm reading will be the same as someone else IF they have a Hannah pen AND they also use hannahs cal solution...he understoof totally what i was asking and said they get many calls weekly about this....and forgive my caps i just want to emphasize not yell...okay so I again have doubts...and I want this answered and I will tomorrow with my buddy, who is a chemist, i just have a bio degree :eek:( and I am going to call oakton tomorrow and hannah and get an answer...I also have seen these charts and I am fairly certain i asked the oakton tech guy about that, I think he said those charts around these forums are not accurate if calibrating pens correctly or something like that, really dont matter without a source that they came from...i mean c'mon, it just makes sense to me that if ppm readings were diff then why do they sell different types of calibration solution with the conversion metrics listed on bottles..??? never mind I know how i would answer that so anyway i gotta trim, and I like this forum, i will get a friggin satisfactory answer out of someone tomorrow..because look at that chart...the way i run my shit, 200ppm diff would destroy 10k in meds....i order paclo and triacontanol direct and have a program going that 200ppm of any ionic salt would ruin it...i want an answer from two of the three manufacturers that agree and then i will be happy....i dont mind bugging tech support, gives me the shits and giggles to rock their boat...lol
 
okay...im sending my degree back...yes this system is screwed up..why don't they just display ec. I know that the answer is that they wont sell as many meters im sure..

I stand corrected...and I will get some re-schooling....
 
You know I am the type of person that likes correct answers...these days I suppose i could be considered ocd, but what the hell it works for me. I would just like to say that after going back over this stuff a few times I do get it and Slim and Hog are correct. But I know you guys are definitely smart, and I consider myself reasonably smart, so given that it really seems like a pisser that it takes this much investigation and research to get the picture? I am kinda of pissed about this right now and other issues in the past having to do with getting correct information from companies that sell to us, and are making a pretty penny at that. Nutrient companies will not give ingredients because the feds and almost all states allow some organic ingredients to be left off. It took so much effort to find out the PGRs used. I guess one example would be Roots Excelurator, or Gravity, Bushmaster, Voodoo or Tarantula (one of them or both)....I do understand the need to protect proprietary info, but some of us are serving actual Medical Patients. The recent issues concerning Paclobutrazol is a great example.

I know i am ranting, and to get back on point, we growers buy a lot of meters from Hanna, Eutech, Truncheon etc...and we are buying products that are probably higher profit margin items, so why the hell cant they standardize things so that the growers out there that do not have to spend so much time learning something that should be reasonably simple to understand. We just want to put our nutes in and take our $100 instruments and be able to take a reading and get on with our other work. Granted I have a weird nute program to most people, but I am successful and average w/CO2 close to .75 gm/watt under 600s. But it is VERY sensitive and I know now that I have been lucky that Technaflora nute readings are evidently fairly accurate on Oakton meters...as I mentioned before some of my additives potentiate fertilizer salts and I am really surprised, now anyway, that I haven't burnt any of my runs...I am past 50 runs about...and I have answers now for some root problems i had when i switched to Sure To Grow...but thats another story..

I am really disappointed in myself for sounding so strident in my first post, so I apologize and think I am going to try and put all these different info sources together and after I call Oakton and Hanna today see if I can put together a post that someone can repost into a sticky maybe, if I am able to consolidate all this info into something easier to understand. This thread is good, and it schooled me, but it did take quite a few readings, and I think you guys went through the same thing.....

Okay rant over... and again thanks for posting that chart and being patient with my pompous sounding post....I definitely sounded like a dick

thanks
 
I am really disappointed in myself for sounding so strident in my first post, so I apologize and think I am going to try and put all these different info sources together and after I call Oakton and Hanna today see if I can put together a post that someone can repost into a sticky maybe, if I am able to consolidate all this info into something easier to understand. This thread is good, and it schooled me, but it did take quite a few readings, and I think you guys went through the same thing.....

Okay rant over... and again thanks for posting that chart and being patient with my pompous sounding post....I definitely sounded like a dick

thanks

As you saw in the thread, I beat my head against the wall trying to understand what Slimm was so patiently trying to explain to me. And that's the beauty of 420 forums, growers helping growers. ;)
 
As you saw in the thread, I beat my head against the wall trying to understand what Slimm was so patiently trying to explain to me. And that's the beauty of 420 forums, growers helping growers. ;)

Yes i am going to enjoy it here. I kinda passed over this and got settled in on another one which is like it is here, serious growers mainly...That can spell..haha

So Yes, I did get schooled here and much appreciate it. I didn't get to call Hanna or anyone else today..Was putting a new water system in and was short 2 hose clamps....TWO HOSE CLAMPS...I live above 10k ft elevation and had a 2 hour drive to town and back...then one of the hose bibs had a bad seat...so my day was not very productive...and to top it all off, went to local hydro shop to get them to special order the correct cal solution for everyone as she has been stocking solutions used for salinity meters/brine, and ended up having to explain this to about 4 different people and thank goodness they got it a lot quicker than i did...

and to the MOD, sorry about that link to that other forum, i should have read your posting rules better...

Okay, now anyone want to talk about what they think is in Roots Excelurator..haha...we have some people where i live who are going to get CSU to find out if Rob at H&G stuck his foot in his mouth...he told someone that he witnessed, himself, the bennies under a microscope at Beneficial Laboratories...a friend of my gf who is a organic chemist used his home setup and found NADA/zip/zero, nothing but a crystalline structure after drying on slide...he is culturing it in agar now to see what rocks out..I am very interested in this, as I believe that RE does work, just not sure how, and i dont think its alive w/anything..I used the RE w/H2O2 very successfully...hmmmmm okay im out
 
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