Hanna Phosphorus checker

[MnFish1]

That was exactly my point! Thank you. He keeps saying that Hanna says 5 mins blah blah blah. The test is taken in 5 mins and yet 2 seconds later, with the same bottle, same liquid, same 5 minute window... it gives a different result. He says that when you keep pressing the button it's meaningless. It's not. It's reading the same sample and should give around the same result, yet it doesn't. Some people just can't admit when they're wrong.

I can see a margin of error because it's reading in ppb, but the difference is too great. I also don't buy into a company trying to make excuses for their product, like the time out window that's never corrected. I followed the instructions to a tee, then double check it by hitting the button to read it again right away after the first result. Two seconds later should not yeild a different result.

I actually don't believe it's reading the sample itself directly. I think there must be some algorithm built-in with the timer. That would be the only explanation imo, and why they never fixed it after so many complaints.

I tried this today - put in the C1, took it out - added reagent, mixed it 2 minutes, put in C2, pressed the timer -waited the 3 minutes - the result came up. When I tried to get a second reading after the first 2 seconds later the unit displayed briefly another number (a negative number) and shut off. I tried it again - went tbrough the process in the instructions after the timer stops and the result is shown, pressing the button again turns my unit off. So Im not sure how you're getting 'repeated' readings - because it doesn't work on my machine at all.

I then tried doing the test your way - without pressing the timer button - but timing the final 3 minutes myself. If you merely press the button when you put the C2 in immediately - the result is 0, if you click the button again - it turns off. If you just put C2 in - without pressing the button and wait 3 minutes without the timer starting - and then press the button a result is shown - if you press the button again - to do a second reading - it turns off. How are you doing these repeated readings?

 

[MnFish1]

I just tried to replicate this with my ULR which is about 3-4 years old. After the 3 minute timer (5 minutes after adding reagent and start to mix), I get a reading. My reading was 4 ppb. I hit the button to get a second reading and the unit simple turns off. I repeated this several times and it seems like when I hit the button after I get a reading, that results in turning the unit off. Apparently, you have a "different" version and maybe newer.

Not to upset anyone, but perhaps Hanna included an unadvertised "feature" for those looking for an easter egg hidden in the product and fore those who refuse to simply follow the instructions

[Sorry, MnFish1, I couldn't resist. I know you prefer the pragmatic approach of simply following proven instructions and not deviating. I completely respect that. But, I also appreciate the "playful" and curious folks out there exploring outside the boundaries to see what can be learned. Unfortunately, this often has those curious folks coming back and asking questions that us pragmatists can easily answer with the manuals alone. From you phone calls to Hanna, it seems like they are unwilling to share any more that that either. And I can understand why they don't]

I like experimenting too - im a fun person lol. BTW as I posted before - my unit immediately shuts off (and its a new model) after the result is displayed - you cant get a 'second reading'.. Maybe Hanna took that option of multiple readings away because they weren't accurate... Perhaps the people doing 2 immediate readings are doing something different? Maybe they can explain how they get 2 readings.

In any case - todays experiment - I did on the timing of the machine:

If you turn it on - to where is says 'add c1' - if you do nothing - it shuts off after 3 minutes inactivity.
If you go up to the point where it says 'add c2' and do nothing - it shuts off after 3 minutes inactivity. (meaning you have 3 minutes to take C1 out - add reagent mix 2 minutes and get it back in the checker)
If you press the button (but dont hold it down to get the timer - ie dont wait the 3 minutes) you get a result or 0 or 1 - which is not accurate. Pressing the button again shuts the unit off
If you use the timer for 3 minutes, wait for the results , the unit shuts off 3 minutes after displaying the result.

 

[MnFish1]

That was exactly my point! Thank you. He keeps saying that Hanna says 5 mins blah blah blah. The test is taken in 5 mins and yet 2 seconds later, with the same bottle, same liquid, same 5 minute window... it gives a different result. He says that when you keep pressing the button it's meaningless. It's not. It's reading the same sample and should give around the same result, yet it doesn't. Some people just can't admit when they're wrong.

I can see a margin of error because it's reading in ppb, but the difference is too great. I also don't buy into a company trying to make excuses for their product, like the time out window that's never corrected. I followed the instructions to a tee, then double check it by hitting the button to read it again right away after the first result. Two seconds later should not yeild a different result.

I actually don't believe it's reading the sample itself directly. I think there must be some algorithm built-in with the timer. That would be the only explanation imo, and why they never fixed it after so many complaints.

I was able one time to duplicate what you are talking about - i.e. pressing the button again - and getting a second number. The second number was much different and a negative number - suggesting it was just a glitch that it was even displayed. I think the machine is designed to 'turn off' after the result is displayed - and the button is pressed - because that is what happened every other time I tried to duplicate what you are talking about.

The 'time out window' is set the way it is because the test has to be read within. a certain time to be accurate.

By the way - the test can be read at 5 minutes +- 15 seconds. to be 'accurate'. But the checker (at least not mine) is not designed to do 2 readings like you are trying to do - I dont think thats a bug - I think thats the design of the machine...

 

[XNavyDiver]

I like experimenting too - im a fun person lol. BTW as I posted before - my unit immediately shuts off (and its a new model) after the result is displayed - you cant get a 'second reading'.. Maybe Hanna took that option of multiple readings away because they weren't accurate... Perhaps the people doing 2 immediate readings are doing something different? Maybe they can explain how they get 2 readings.

In any case - todays experiment - I did on the timing of the machine:

If you turn it on - to where is says 'add c1' - if you do nothing - it shuts off after 3 minutes inactivity.
If you go up to the point where it says 'add c2' and do nothing - it shuts off after 3 minutes inactivity. (meaning you have 3 minutes to take C1 out - add reagent mix 2 minutes and get it back in the checker)
If you press the button (but dont hold it down to get the timer - ie dont wait the 3 minutes) you get a result or 0 or 1 - which is not accurate. Pressing the button again shuts the unit off
If you use the timer for 3 minutes, wait for the results , the unit shuts off 3 minutes after displaying the result.

This is my exact experience also.

 

[Forsaken77]

I was able one time to duplicate what you are talking about - i.e. pressing the button again - and getting a second number. The second number was much different and a negative number - suggesting it was just a glitch that it was even displayed. I think the machine is designed to 'turn off' after the result is displayed - and the button is pressed - because that is what happened every other time I tried to duplicate what you are talking about.

The 'time out window' is set the way it is because the test has to be read within. a certain time to be accurate.

By the way - the test can be read at 5 minutes +- 15 seconds. to be 'accurate'. But the checker (at least not mine) is not designed to do 2 readings like you are trying to do - I dont think thats a bug - I think thats the design of the machine...

Maybe my unit is defective and doesn't shut off. I'll try it again today and tell you exactly how I did it.