The fluid rig has two primary standards:
The principle of the two standards is different; The drum has a static start and stop. The Proverloop is a piston prover with a free running piston. The Proverloop has a "flying" start and stop.
With a liquid turbine meter DN50 both standards are compared.
Every five years (calamities or unexplained abnormalities earlier) is:
In this regime is the following applied:
For the relevant pressure and temperature sensors, a calibration takes place with an annual frequency.
The calibration of or research on flow meters of third parties are always against the reference standards. On request it is possible to calibrate the meters by 1 of the primary standards. The calibration of a flow point is measured three times. If there is a measurement out of line, to be judged by the operator, two additional measurements will follow. The judgement complies with the specifications concerning the reproducibility of the flow meter on the stand.