Scale Calibration: Level-Up Your Balance – Correct Balance Installation Guide
One of the most important aspects of scale calibration and setting up a balance is ensuring that it is level. Scale calibration can affect numerous aspects of a balance’s performance (stability, repeatability corner-load etc). However, ensuring that the bubble sits in the centre levelling eye can be an awkward and time consuming process. This simple guide can help speed up the process and assist with any difficulties you might be experiencing.
1. Check the bubble of the Levelling Eye
The levelling eye is usually located at the Front or Rear of the unit, but is sometimes located under the pan for larger capacity units.
The principle is the same as that of a spirit level. The ideal position of the bubble is dead centre of the circle. This will give the balance its correct conditions for proper functionality. Its position should be relative to the circle as this will inform your next step.
2. Ensuring your balance is Stable
It is important to check the surface and environment in which the balance is to operate. The environment should be:
- As flat and smooth as possible
- As far from sources of vibration and air movement as possible
- As far from direct sunlight as possible
If the bubble is in the centre of the unit it is often easy to assume that no further action is required, but it is also important to ensure that all the feet (adjustable or fixed) are contacting the surface.
If there is a gap between a balance foot and the surface when a load is applied, the balance may shift so that the unit is no longer level or causes the reading to fluctuate as the position of the balance is in constant flux.
3. Bringing the bubble to the Centre
Check how many adjustable feet your balance has (usually 2-4) and their position. When the bubble is misaligned from the centre it is often easier to retract all levelling feet as far as possible (turning all anti-clockwise) to start from a stable base.
The bubble will always move towards the corner of the foot that is being turned clockwise. Likewise, turning feet anti-clockwise will send the bubble away from that corner, in the opposite direction.
To move the bubble in a straight line rotate both feet along the edge of the desired direction (clockwise to move towards/anti-clockwise to move away).
Once the bubble has reached a central position to check that the unit is stable press gently on each of the 4 corners to ensure there is no significant movement of the bubble or the unit. Then, if necessary, slowly adjust the feet until all are in firm contact with the surface.
4. Your balance is now level
It can be useful to mark on your bench the position of the balance by drawing round each corner onto the bench. That way you can easily notice if the balance has been moved without your knowledge.
It may also be worthwhile placing a note on the balance to the effect of “PLEASE DO NOT MOVE THIS EQUIPMENT AS THIS CAN ADVERSELY AFFECT THE READING”. This may discourage people moving the unit to clean it or for their own convenience.
UKAS Scale Calibration Services
Precisa offers fully accredited scale calibration services. Our calibration services accreditation complies with regulatory body requirements.