Flow Measurement · Glossary

What is Meter Factor?

Symbol: MFdimensionless, close to 1Flow Measurement

Meter factor is the ratio of the true volume from a prover to the volume indicated by the meter during proving.

Meter Factor Explained

In custody transfer a meter is proved against a known volume. The meter factor corrects the indicated volume to the true volume.

Changes in meter factor over time show wear, fouling or a change in fluid. Trending it is a simple condition check.

MF = V_prover ÷ V_meter and K_new = K ÷ MF

V_prover	corrected prover volume
V_meter	volume indicated by the meter
K	K factor in use

Example: Prover 1000.0 L, meter 995.0 L: MF = 1.0050. A K factor of 50 pulses/L becomes 49.75 pulses/L.

What is Meter Factor?

Meter factor is the ratio of the true volume from a prover to the volume indicated by the meter during proving.

Should MF be applied or K changed?

Either, but not both. Custody systems usually keep the original K and apply MF so changes are traceable.

What MF change is a problem?

Your measurement procedure sets the limit; a sudden change between provings needs investigation.

What factors affect the stability of flow meter readings?

A practical guide on instrumentationblog.in with more detail on meter factor and how it is applied on real plants.