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Hello -
I have a SW replacement setup with doser 2.2 Maxi to run several times a day.
It ran for months as expected. with 3 or 4 doses day at varied volumes (based on KH director and ReefBot lab usage)
I updated firmware a day ago on the dosers and P4 to latest versions.
I also adjusted the doses down from 200ml and 300ml to two doses per day at 125ml (reefbot offline).
Now I am getting oddball dosage amounts again. Notice that instead of 125 I got 124.8 and then 125.2
I am (again) very concerned here that I can't trust the dosing schedule or actual throughput or reporting- especially for critical doses like Alk, Ca, Mag, KH director, etc.
See image below - prior dosages were proper, but the new 125ml dosage is not.
Why is there an adjustment being applied????
Settings
@Gaël @Vinny@GHLUSA can either of you offer some insight?
I think this is a pretty serious issue that keeps cropping up in one form or another,
Math or rounding issue?
Specification is .1ml
240ml a minute is 4ml per second.
31 seconds is exactly 124ml
32 seconds is exactly 128ml
31.25 seconds is exactly 125ml
.025 seconds is exactly .1ml
There is no oddball rounding issue here unless the the .025 seconds is being rounded to .03 seconds and that changes the advertised or effective resolution from .1ml to .12ml
It then follows that
125ml desired dose can't be resolved to .12ml resolution and not only that but it would appear that error is further compound by rounding the .12ml to .2ml !!
But - it gets worse, because we are now undershooting or overshooting by .2ml which is a .4ml total range for a 125ml desired dose... nowhere close to .1ml resolution. This appears to be rather significant!
Thus 124.8ml or 125.2ml being reported (or dosed and reported?)
The question then becomes is the rounding issue a charting/reporting issue only and the weird "adjustment" just on paper and not really happening (I.E. the reporting math and the stepper math are not the same) and the dose WAS actually 125ml ?
Or
Are the dosages being mangled by the rounding and the P4 trying to adjust the following dose to compensate?
I have a SW replacement setup with doser 2.2 Maxi to run several times a day.
It ran for months as expected. with 3 or 4 doses day at varied volumes (based on KH director and ReefBot lab usage)
I updated firmware a day ago on the dosers and P4 to latest versions.
I also adjusted the doses down from 200ml and 300ml to two doses per day at 125ml (reefbot offline).
Now I am getting oddball dosage amounts again. Notice that instead of 125 I got 124.8 and then 125.2
I am (again) very concerned here that I can't trust the dosing schedule or actual throughput or reporting- especially for critical doses like Alk, Ca, Mag, KH director, etc.
See image below - prior dosages were proper, but the new 125ml dosage is not.
Why is there an adjustment being applied????
Settings
@Gaël @Vinny@GHLUSA can either of you offer some insight?
I think this is a pretty serious issue that keeps cropping up in one form or another,
Math or rounding issue?
Specification is .1ml
240ml a minute is 4ml per second.
31 seconds is exactly 124ml
32 seconds is exactly 128ml
31.25 seconds is exactly 125ml
.025 seconds is exactly .1ml
There is no oddball rounding issue here unless the the .025 seconds is being rounded to .03 seconds and that changes the advertised or effective resolution from .1ml to .12ml
It then follows that
125ml desired dose can't be resolved to .12ml resolution and not only that but it would appear that error is further compound by rounding the .12ml to .2ml !!
But - it gets worse, because we are now undershooting or overshooting by .2ml which is a .4ml total range for a 125ml desired dose... nowhere close to .1ml resolution. This appears to be rather significant!
Thus 124.8ml or 125.2ml being reported (or dosed and reported?)
The question then becomes is the rounding issue a charting/reporting issue only and the weird "adjustment" just on paper and not really happening (I.E. the reporting math and the stepper math are not the same) and the dose WAS actually 125ml ?
Or
Are the dosages being mangled by the rounding and the P4 trying to adjust the following dose to compensate?
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