A meter, by definition, needs to measure – and totalize – the amount of fluid that passes through it. Whether the fluids are diesel or gasoline, or whether they are oils and lubricants with higher or lower viscosity.

Hence, the need of a measurement as accurate as possible while considering the precision indicated on the technical sheet of the device itself. To achieve this, you need to correctly calibrate your meter. And periodically conduct checks and re-calibration operations; when necessary. Corrosion, impurities of the fluid, and the use itself, are variables that cause wear, over time, to even the most resistant flow meters and makes calibration necessary to ensure accurate measurements. According to the International Vocabulary of Metrology, calibration is

“an operation that, under specified conditions, first, establishes a relation between the quantity values with measurement uncertainties provided by measurement standards and corresponding indications with associated measurement uncertainties and, second, uses this information to establish a relation for obtaining a measurement result from an indication”.

So, how do you obtain a correct calibration? Each meter has its own method. As for all PIUSI flow meters, you can find all the video tutorials to correctly perform the operation here.

These are some tips for all meters that we suggest you stick with.

1. ALWAYS CALIBRATE

Even if the meter is already calibrated by the manufacturing Company (PIUSI calibrates all their meters during the production and testing phases), our advice is to re-calibrate it again. This is because the meter has to adjust to the real working condition: temperature, plant, fluid.

2. AIR?

To be sure that the meter hasn’t counted the air that may be present in the system and that may have passed through the device, we always recommend discharging the air from the system and using a good foot valve on the suction side.

3. FIRST INSTALLATION, THEN CALIBRATION

Calibration is a procedure that has to be carried out only after the dispense system is fully installed, not before. This is because all the components of the system directly affect the transfer itself: the pipe length, the presence or lack of a filter, temperature… these are all variables that may change the result. Therefore, the rule is simple: first installation, then calibration.

4. TEMPERATURE: FRIEND OR ENEMY?

Huge temperature changes, especially in the summer/winter passage and vice versa, have a significant impact on the final count by acting on the fluid itself (which becomes, for example, more or less viscous). For this reason, it is good to recalibrate whenever there is a significant thermal change.

5. EACH FLUID HAS ITS OWN CALIBRATION

The calibration has to be carried out with the same fluid that will be used during the transfer procedure; it is not possible to calibrate a flow meter with oil that will be used with diesel.

6. GRADUATED CONTAINER: YOUR ALLY

How much fluid has to be dispensed to have a correct calibration? There is no universal answer. Certainly, it is necessary to use a fair amount of fluid depending on the fluid that will be dispensed. We suggest to always use a 20 lt graduated container in which to dispense the fluid during the calibration procedure. If it is diesel, we suggest dispensing the total 20 liters. If it is an oil, 5 liters should be enough.

The indications above have to be considered as advices for the calibration. The technical product manuals - which are published online and are in all the packages - and online video tutorials are valid for all technical indications and operations.