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Knowledge center Mechanical Equipment How do you calibrate an electric scaleHow do you calibrate an electric scale?
Written by Nick Groenewoud | Last update: 13-7-2021
With frequent use, a measurement error may occur in an electric scale over time. This means that the scale does not indicate the correct weight when weighing. You can determine this measurement error by calibrating the scale. During the calibration, you compare the result of the measurement with the (inter)nationally determined standard value. But how does calibrating an electric scale work? In this article, our specialist explains this.
Approved or not approved?
Before you start calibrating the scale, you must check whether the scale has been inspected.
If so, then it is not permitted to calibrate the scale yourself (and this is not possible; during the inspection of an electric scale, the mechanic blocks the calibration function). An approved scale can be recognized by the seal. Of course, an approved scale may be calibrated by people who are certified to do so.
Preparation
Before you start calibrating an electric scale, you must make the following preparations:
- Connect the scale to the mains.
- Place the scale on a firm surface.
- Check whether the scale is level and stable.
- Check whether the weighing platform is placed straight and correctly on the scale.
Calibrating an electric scale
For calibrating an electric scale, you use a calibrated weight. The calibration method differs per model. How often you need to calibrate an electric scale strongly depends on how intensively it is used and how the device is handled. Even so, you could generally assume that with daily use, an electric scale should be calibrated every 3 months.
Difference between calibrating and gauging
The concepts of calibrating and gauging are often used interchangeably, but they are not the same thing. With calibration, you determine the extent to which the scale deviates from the standard. You do this yourself and there are no consequences to this: you are simply determining the accuracy of the measurement tool. Gauging may only be performed by a qualified technician. There are consequences to this: if the scale is rejected, they may not be used again until after it has been adjusted by a technician.
If a manufacturer brings a scale onto the market that is to be used for trade purposes, they must first have it tested by an official body such as the NMI (Netherlands Measurement Institute). If all requirements are met, a Test Certificate is issued. This means a scale can be approved by the manufacturer from that moment on.
Determine whether a scale must be approved before purchasing it, as approving it later involves additional costs. A gauging inspection is required if you are going to use the scale for trade purposes (if you are going to use the scale internally for inspection purposes, then this is not required). The owner of a scale is responsible for the correct operation of the scale and for the inspection markings/seals that are present on an approved scale.
Note: a scale with a calibration certificate but without approval may not be used for trade purposes.
Calibrating at your own risk
Calibrating an electric scale is always at your own risk. If you would rather have an electric scale approved by a certified party, then please contact the manufacturer of the scale.