Problem with lab scales

[STRABAG]

Hello,
I've a problem with my lab scales.. Lately I've to seen that my sclales under the effect of temperature give diffefrent result - after heating the results goes to minus. So I've a question..
What I can do in this situation?
I planing buy a new scales (something like this: <suspected spam removed>)
because my current scales has a couple yeras, but now i'm affraid that is typical for scales.. is it?

 

[Born2bwire]

I think all scales that you will buy are calibrated to operate within a specified temperature range which should be given in their specifications. I think the simplest thing to do is use an insulating disk between your sample and your scale.

 

[Murloc]

yeah insulating would be an idea, otherwise recalibrate when it's already warm, which could be difficult.

 

[carslos]

apparently many high precision lab scales have temperature issues so I would make sure that the one you are looking to buy has an operating temperature range that meets your requirements. Also if you are concerned about temperature I would look into their scales with automatic internal temperature. It looks like these will calibrate automatically when the temperature changes which is what Murloc recommended you do when the scale warms up. One of these could be a good buy <probable spam removed -Admin DrPizza>http://www.torbalscales.com/laboratory-balances/precision-advanced-series.html

 

[Paperdoc]

I am assuming that you mean the result changes when the SCALE itself is warmed, and not just when you place a warm item on the pan to weigh. (Of course, any item to be weighed must be cooled to room temperature to avoid disturbance from air currents.) If the scale itself changes when warmed, and assuming that the temperature change is not huge, I would expect you need to do two things. The first is to re-TARE the scale to read zero with an empty pan. The other is to ensure that the temperature is stable, and not causing changes as you use the scale.

By the way, how is the temperature of the scale changing? Is the room temp changing? Is there a warm air flow near it? Can you prevent this temperature fluctuation easily?

 

[carslos]

Well, true precision scales are built with electromagnetic load cells which are sensitive to temperature variations , so when you first turn the scale on all the electronic components i.e. the LCD are heating up and raising the temperature inside of the balance. So the scale needs to compensate for that temperature change, but from my experience the room temperature has very little effect on it, it’s what is happening internally in the scale. I defiantly agree – always TARE before weighing.

 

[Seraphimcaduto]

What temperature range are you working in? Most scales are calibrated at STP (20C) and will fluctuate within a range for temperature. The site that you linked to only has scales that operate from 15-30C, so if you need to weigh something outside of that range, you would need a scale that has an operating range that your sample falls into.