Approximately in the year 3,500 BC, commerce was one of the most important activities, especially in everything related to the exchange of products. Due to this evolution in this commercialization, the Egyptian people were forced to weigh and measure those products destined for sale. For this reason, the emergence of a new instrument that collaborated in this aspect was essential. These are the beginnings of the history of the balance.
It is necessary to have the right laboratory-weighing device that provides you and your personnel the needed accuracy that gives you reliable results. There are different kinds of balances; in this case, we are presenting you with the electronic ones. These devices are used for measuring samples from .01 mg (0.0001 g) to 1 g readability. Electronic balances must deliver accurate results with a great amount of precision.
This feature is precisely the one that becomes fundamental in these devices. Any kind of laboratory need to have precision weighing in order to deliver accurate results. Even though the requirement for highly accurate weighing for the preparation of reagents, standards, and calibrators has diminished, many laboratories use precision balances for periodic checking of the accuracy of mechanical pipettors.
Electronic balances function
In case you are wondering how electronic balances work, we will explain that to you. But first, you need to understand how they are constructed. You should know there are two basic types of electronic balance designs. The first one is “Electromagneting balancing type” and the second one is “Electrical resistance wire type (load cell type). What these balance types have in common is the fact that they measure the force that acts downward on the pan. This force is converted to an electrical signal and displayed on a digital display.
At this point, you might be wondering why do electronic balances display mass values when that is not what they measure? It is because the reference standards for mass are weights, which are placed on a pan to inform the electronic balance that a given force is equivalent to a given number of grams, which is used for conversion. Consequently, electronic balances that do not perform this conversion accurately cannot display accurate mass values.
Electronic balances accuracy
Having the right electronic balances in your laboratory is a fundamental factor when it comes to performing experiments and procedures that require their use. That is why we are letting you know 4 important components to the testing of a precision laboratory balance: reproducibility, linearity, calibration, and cornerload.
- Reproducibility refers to the instrument’s ability to repeatedly deliver the same weight reading for a given object. It is expressed as a standard deviation. Standard deviation, or reproducibility, is often an advertised performance specification for a laboratory balance.
- Linearity is the characteristic, which quantifies the accuracy of the instrument at intermediate readings throughout the weighing range of the instrument. The weighing range of the instrument is similar to the analytical measurement range (AMR) of a laboratory test. Since a laboratory balance will often be used to weigh items much smaller than the capacity of the instrument, this is a critical aspect.
- Calibration refers to a comparison of the weight reading of a given mass standard, and the actual value of that standard. This measurement is often done at full capacity.
- Cornerload errors are those errors associated with different positions on the weighing pan of the object being weighed. A given object should produce the same reading, regardless of its position on the weighing pan.
Finally, we also recommend you to inspect your electronic balance on a daily basis. Frequent inspections will provide you with the information of the balance status, since they remain silent, no matter how large the sensitivity error is. This means that problems can be difficult to notice. You should perform these inspections before starting a measurement. The first thing you need to do is to visually inspect the exterior for any contamination or anything unusual. Secondly, you need to confirm everything functions properly, such as switches and opening/closing the door. Finally, confirm that the zero-point display (without a load) is stable.
Finally, to see the different options please visit our Electronic Balances.