Comments on: TECH Tip: Reduce Electronic Scale Drift with Static Guard Spray

By: J. Ryan Nielson

J. Ryan Nielson — Sat, 18 Jan 2020 03:49:31 +0000

Dryer sheets sound like an excellent idea! I am going to hypothesize a mechanism or two by which static charge fouls up scale readings.
Model 1: First of all, nearly all electric measurements are eventually reduced to a potential – a voltage.

I would guess that with scales the pressure on the pan squishes a piezoelectric transducer. This pressure on a quartz or ceramic element electrically polariazes the ceramic. Think of those squishy toys where you squeeze them and the eyes bug out. One eye positive, and the eye on the opposite side negative.

A voltage probe then measures the voltage from those separated charges, and the remaining circuit converts that into a weight and displays it.

A stray charge imbalance produces a field or voltage which combines (superimposes) with that produced by the piezoelectric sensor. The voltage probe can only measure the combination. That is, the stray charge adds noise to the weight signal.

Model 2. Piezoelectric devices are reversable. -Turn about is fair play. . .
By that I mean that while squishing the ceramic makes a voltage, putting a voltage across it can squish the ceramic too.

This is why we have both piezoelectric speakers and piezoelectric microphones.

By: Corey

Corey — Tue, 14 Jan 2020 00:34:49 +0000

I wipe my scale and the area around it with a used dryer sheet. I put it in the powder hopper after I dump the powder at the end of a session. Replace the sheet when I think about it.

By: Michael Moore

Michael Moore — Mon, 13 Jan 2020 20:44:38 +0000

Drifting zero from environmental static would indicate to me that the processor board(s) are not humidity sealed.

By: Randy

Randy — Mon, 13 Jan 2020 03:00:51 +0000

Ditto on Robs comment. Doesn’t the spray accumulate over time ? Do you wipe down the old layer of spray ?

By: Rob

Rob — Sun, 12 Jan 2020 21:03:29 +0000

There isn’t a description how of the usage. Is he spraying directly on the scale, or just in the air in the around it?

By: David Lawson

David Lawson — Sun, 12 Jan 2020 17:29:57 +0000

Every laboratory uses some form of a static guard on their scales regularly.
It improves instruments no end and should be used for shooting scales too.