Sensor repeatability
Sensor repeatability
(OP)
Can anyone give a quick explanation or a link to an explanation of what sensor repeatibility would be measuring exactly?
I have two different sensors I'm using in a project, and for both sensors the repeatability is given as +/- 1 mm. Both sensors detect the presence of liquid when there is liquid present on the sensor. I searched around but couldn't find much explanation. I found a definition that said "Repeatability, as the name implies, refers to how often a sensor under the same input conditions will return the same value," which makes sense to me, but that doesn't explain to me why both sensors would have their repeatability given in mm.
Thank you in advance for your help.
I have two different sensors I'm using in a project, and for both sensors the repeatability is given as +/- 1 mm. Both sensors detect the presence of liquid when there is liquid present on the sensor. I searched around but couldn't find much explanation. I found a definition that said "Repeatability, as the name implies, refers to how often a sensor under the same input conditions will return the same value," which makes sense to me, but that doesn't explain to me why both sensors would have their repeatability given in mm.
Thank you in advance for your help.





RE: Sensor repeatability
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RE: Sensor repeatability
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RE: Sensor repeatability
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RE: Sensor repeatability
While it's not a completely syntactical English description, what part of that was unclear?
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RE: Sensor repeatability
RE: Sensor repeatability
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RE: Sensor repeatability
What is the question? And why?
Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.
RE: Sensor repeatability
>Why is the repeatability measured in "mm"? If this sensor is for either the presence or absence of a liquid, why would repeatability be in "mm"?
Because the trip point depends on the sensitivity setting, the material, the and geometry of installation, none of which are predictable.
However, for the same material, sensitivity setting and geometry, the trip point will repeat within ±1mm. That might be 3 mm distance away from the probe tip, or having the probe tip immersed 4 mm, or some other 'distance', but for repeating conditions, the trip point is repeatable.
>Are HRingm and I just over-thinking this and the "mm" refers to liquid level?
Yes, but ±1mm with respect to the level it tripped before and before that, for repeatable service conditions. Change the service conditions and the level at which the trip point occurs varies.
>That the liquid level required to trigger the sensor will be within +/- 1 mm? Yes, within +/- 1 mm of wherever the sensitivity setting for that material and that installation produces a trip point.
>This is a bit aggravating since the sensor specs never tell us what liquid level is required to trigger the sensor, just the repeatability of it.
The manufacturer's crystal ball was foggy the day he shipped your unit and he couldn't tell what material you have or where you set the sensitivity or how you installed it. Maybe next time . . .