Watthour Meter Principles 1 - Instant Video
This 38-minute video covers the operating principles and physical construction of electromechanical watthour meters. Magnetic principles and their relationship to current flow are examined to show what makes the meter disk spin.
Basic Components – 5 minutes
Identifies the basic components of a typical electromechanical watthour meter. Identifies the function of each component in a typical electromechanical watthour meter.
Fluxes – 8 minutes
Identifies the fluxes at work in a watthour meter and describes where each flux originates. Describes how watthour meter fluxes are distributed in a meter. Identifies the direction of each flux at given points in time.
Driving the Disk – 10 minutes
Identifies the four driving fluxes that cause a meter disk to rotate. Describes the relationship of the fluxes at four points in time. Explains how the fluxes interact in a watthour meter to drive the disk.
Explains why the potential coil flux must be lagged behind the current coil flux, and by how much. Identifies the components in a watthour meter that cause the potential coil flux to lag the current coil flux, and briefly explains, using phasors, how this is done.
Controlling Disk Rotation – 7 minutes
Explains why it is necessary to control the rotation of a meter disk. Identifies the component in a watthour meter that controls the rotation of the disk, and briefly explains its operation.