1. n. [Production Logging]

A device for determining the water holdup in a producing well by measuring the capacitance or impedance of the fluid. The holdup meter is used to produce a capacitance log. Since water has a high dielectric constant, and hence capacitance, it can be distinguished from oil or gas. The meter is a coaxial capacitor, with fluid flowing between a central probe and an external cage that act as electrodes. The meter has often been combined with a packer flowmeter or a diverter flowmeter, so that all the fluids in the well pass through the meter.

Synonyms: capacitance meter

See: capacitance log,  dielectric constant,  diverter flowmeter,  holdup log,  packer flowmeter,  production log