Grounding AND FX120i scales?

[DenisA]

Hi all,

When you ground a set of digital scales during use, what do you ground the wire to?

Cheers,

[RAVEN]

EARTH

[Barry Davies]

Why would you want to earth the scales? If they required earthing the plug would be 3 pin.

[DenisA]

There's a body earth screw on the side of the scale. It's recommended that an earth lead is attached if static starts getting high.
It's advised that the scales work best in an environment of above 35% relative humidity (from memory). I've noticed that with these cold dry nights the scales aren't as steadfast in holding the zero as they usually are. They're still unbelievable compared to a strain gauge scale, but have been wondering a little more in the last week.

I thought I'd try connecting the earth lead.

[IanP]

Denis, I just use an alligator clip lead from Jaycar and clip it to the metal body of an earthed appliance I have on my loading bench. I also do all my loading on an anti-static mat I got from Jaycar. Electronics background, so used to using anti-static devices. I sit my RCBS ChargeMaster on the anti-static mat when I'm using it. Its certainly not essential for reloading but my bench doubles for electronic repairs as well so it gets used.

Ian

[DenisA]

Denis, I just use an alligator clip lead from Jaycar and clip it to the metal body of an earthed appliance I have on my loading bench. I also do all my loading on an anti-static mat I got from Jaycar. Electronics background, so used to using anti-static devices. I sit my RCBS ChargeMaster on the anti-static mat when I'm using it. Its certainly not essential for reloading but my bench doubles for electronic repairs as well so it gets used.

Ian

Ian.................. anti static mats! I like the sound of those.

Thanks for the tip on the earth.

I've been running my scales independently of the main and away from other appliances connected to the mains. I run it off a pure sine invertor connected to a car battery....... that's the setup I had with the old scales to improve the drift.

I just found the following description of grounding, it sounds like I should just be able to screws the earth lead to the frame of my bench which is bolted to my slab???
Objects with an excess of charge - either positive or negative - can have this charge removed by a process known as grounding. Grounding is the process of removing the excess charge on an object by means of the transfer of electrons between it and another object of substantial size. When a charged object is grounded, the excess charge is balanced by the transfer of electrons between the charged object and a ground. A ground is simply an object that serves as a seemingly infinite reservoir of electrons; the ground is capable of transferring electrons to or receiving electrons from a charged object in order to neutralize that object. In this last section of Lesson 2, the process of grounding will be discussed.

Static seems to be so important for a steadfast zero when using sensitive electronic scales. I've found a massive improvement if I wipe the scales, balance plate and loading tray down with metho on a rag prior to warming them up and calibrating.

I noticed how massive the improvement was in the past using my Sartorious AY123 strain gauge scales.

I've even seen that in really dry conditions, staticy fingers can cause a disruption as the tray is put on to the scale and taken off.

I'm not suggesting it should be done for reloading, but I've seen scientists in some situations use grounded wrist bands when using lab scales.

I should re-iterate, that the tiny irregular amount of wonder that I'm seeing with these scales is far from a problem. I just thought I'd try the earth lead and see what the difference is.

Thanks for the advice.

[DenisA]

Just thought I'd conclude this thread. I attached a ground lead to my AND scales and screwed the lead to my steel bench leg. I've put a connector in the wire so that I can unplug it to sit the scales on the shelf when not in use without unscrewing anything.

It may be coincidental, time will tell, but so far tonight in an hour of use, with the ground lead connected the scales have been absolutely rock solid in holding their zero. Haven't even drifted .02g.

[aaronraad]

Haven't even drifted .02g.

0.02gr

[mike H]

Haven't even drifted .02g.

0.02gr

Grains or grams ,too many abbreviations these days.
Mike

[DaveMc]

interesting point mike.

it should be g for grams and gr for grains but I go with gn for clarity.

[DenisA]

Sorry my bad, I just assume everybody's talking grains. I know that's not always the case.

0.02 gn.

Spent another couple of hours on it last night (prepping for Natives and Queens with multiple cartridges), still no drift. Except for when I got up and walked past it. The draft briefly disturbs the scales then it resettles perfectly.