There is water in the sample line after each test. They would need to dump it out either after that test or just before it does the next test. If they don’t it will mix with the current SW and throw off the test.
Trident FAQ (official)
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There is water in the sample line after each test. They would need to dump it out either after that test or just before it does the next test. If they don’t it will mix with the current SW and throw off the test.
GabeM
King of... something.
They use the known value of the perastilitic pumps to measure. If you cut off 8" of tubing 8" more water is entering the unit than is supposed to. Any sensor that would be able to accurately measure the small amounts involed in these titrations would cause the unit to be more expensive than $600.
Your saying more water because the resistance on the motor is less? That would make sense.
The water in the 5' length of hose is not enough to fill the Cuvette to the point where the pump shuts off so it is pulling in extra water no matter what.
GabeM
King of... something.
The units are calibrated to pull enough water for the length of the tube + whatever water is necessary for the test presumably based on time. If you shorten the tube then it decreases the amount pulled into the tube (since there is less of it) thus increasing the amount of water brought into the test vial.
I am not sure how accurate that is. Pulling with a pump, especially peristaltic, for 10 seconds on a 10 foot tube or a 5 foot tube would take in the same amount of water (ignoring tube friction calculations and assuming sample intake is at same height). There is never air in the line or anything; the tube is already filled with water.
The amount of time the pump runs is designed to “toss” all the old water in the 8ft line, and then get a new sample from the sump to test. And it would also take into account the amount of tube friction loss loss in 8ft of tube, in order to obtain the correct amount of water.
What I am trying to say is that it would never overflow the vial, it just may be slightly (tiny bit) less accurate due to pipe friction. I damaged the sample tube at one point and ran it at ~3ft for a few months with no noticeable changes to the results
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GabeM
King of... something.
I cannot say for sure but I am assuming the pumps must run in reverse to clear the lines each testing run to clear out saltwater to ensure a fresh sample is brought in every time as this is the only way other than discarding and the trident produces very little waste. This is a popular function of many high end dosing pumps. That is why the tube length cannot be changed, as the line is filled with air at the start of each testing run.
No, it does not run in reverse to my knowledge (I have 2). It simply fills the vial and empties it to prime the line- there is even a function called "Sample priming" which fills the vial and dumps them. Never any air involved on the sample end, which probably helps overall accuracy (no bubble stuck in tubes anywhere).
GabeM
King of... something.
I concede that this makes sense so then the only time sample tube length being shorter would become an issue is during the initial priming.
The tube is not more than 1mm ID which would be 2.3ml of water to clear out the tube.
I had not thought of that for initial priming- but true, that might cause a problem (if it relies on 8ft of tube being empty, and does not drain the vial before attempting to add sample).
Overall its a really cool design. Having a single peristaltic pump and several solenoids means that even if the pump's output changes over time due to wear, ALL of the liquid proportions are effected equally.
Being as important as it is not to cut the feed line, they should write or say it somewhere in the box or set up video. I happened to find it looking thru the FAQ section on their website, unless I missed it. Anyway, will wait a few days before testing it myself and compering it with the trident results. and buy a new feed line once they become available again.
Silver14SS
Valuable Member
Get Started | Trident Installation
Trident Installation: Preface This guide will illustrate how to physically install the Trident. The guide below will walk through the different steps illustrated on the Get Started card included with your Neptune Systems Trident, but the recommended method is to use the Trident Initial Setup...
www.neptunesystems.com
Get Started | Trident Installation
Trident Installation: Preface This guide will illustrate how to physically install the Trident. The guide below will walk through the different steps illustrated on the Get Started card included with your Neptune Systems Trident, but the recommended method is to use the Trident Initial Setup...www.neptunesystems.com
Yup, saw that now, but from the fusion app tutorail it doesn't say that. their website tutorail does i guess. Or maybe I really missed it lol.
Thats what I also got in mine.This is what was in my box, maybe they've changed it up? Anyway what's done is done, no big deal, will have to wait for the feed line to become available to replace mine;Meh
Agreed. After the initialization you mentioned, the tube length plays a very small role. The reduced friction in the tube is pretty minimal. Their warning probably is to obtain the advertised +-.05dkh/15ppm Ca/Mg. I ran with half length for a couple months after I accidentally damaged the tube (rubbed on sharp surface and it was leaking). Only ordered a replacement because I was moving the trident farther away
