Tf100 vs speedstir measurements

[wjr75]

According to pipette the TFP cylinders are more accurate. I can't see the line on the other ones. I really don't think the difference is going to throw numbers off to much in either way. I use the flick of the wrist method of filling it and I'm pretty good at it

 

[brims]

According to the pipette, the TF cylinders are less accurate. The meniscus doesn't even touch the black graduation line, you read the meniscus of water at the bottom of the meniscus for a concave meniscus.

Zoomed cylinders 1 and 2

Zoomed cylinders 3 and 4

"...In any case, you get the true volume of the liquid by reading the center of the liquid in the tube, as shown by the middle of the dashed line in the diagram." - Meniscus, USGS Water Science School

 

[wjr75]

Ya, I'm an Engineer and know how to read it. I think you may be over analyzing it a bit. When I add chlorine or acid I estimate what a quarter or third of a bottle looks like and go from there so that difference isn't going to matter in my case.

 

[brims]

Ya, I'm an Engineer and know how to read it. I think you may be over analyzing it a bit. When I add chlorine or acid I estimate what a quarter or third of a bottle looks like and go from there so that difference isn't going to matter in my case.

The original post was about the differences between the 2 cylinders, which lead to questions about which is more accurate leading to some saying the TF cylinder was correct because there were 2 that matched - this being a false assumption to make. So I posted results that show the accuracy of the different cylinders. Someone basically said "throw out the Taylor tubes because they are less accurate" If someone is going to throw out cylinders due to being less accurate, the less accurate tubes need to be identified; doesn't really seem like an over analysis.

If accurate results weren't important, TFP would be telling people to use test strips and pool stores for results.

 

[WickedAL]

It seems we are all having mixed results. My experiment shows the TF cylinders to be the more accurate. Then again I am by no means an engineer and I was using a simple syringe from my kids medicine drawer. Shame too because the Taylor cylinder stays so much more secure on the SpeedStir. When I use the TF cylinder it spins around and has a slight wobble sometimes.

 

[duraleigh]

Folks, this will get confusing to the tenth millenium (don't sharpshoot me but you can laugh if you like.....that's intentional misuse of the word) if we have 30 tests results and opinions reported.

TFTestkits is working with Taylor to see what we have. There are some other factors involved also. It would be VERY helpful to TFTestkits to not throw a monkeywrench into the works.

Certainly you may post here as much as you like. TFTestkits will not be posting anything for a while because we are using Taylor as our benchmark....not what is reported here. As soon as we get something definitive. We'll post right back up.

Let me add this......you can still use either cylinder (Taylor's or TF-100) but don't use both. What you are looking for is repeatability.....not absolute accuracy.

For example if your initial test of the OCLT is 12.0 and your following test the next AM is 11.0 ppm, you still pass the test.....where the result is accurate or not. So, keep in mind that it is repeatability that is the most importan factor on this test.....not dead on accuracy.

Soon as we get some definitive answers from Taylor, we'll be in touch with valid reports and not guesswork.

 

[taylortechnologies]

When it comes to accuracy, a product with volume gradations molded into the product, like the 9198, will offer more precise results than a product with printed volume gradations. This is inherent in the manufacturing process. The molded indications also offer a longer life to the markings.