Instruments Associated With Electrical Measuring

Electromechanical Induction Meters

• Electromechanical induction meters are the most common meters and measure in watts per hour. An electromechanical induction meter counts and records the revolutions of an aluminum disc inside the meter that is manipulated through a combination of current and voltage within the presence of magnetic fields. The disc is maneuvered by two coils connected to the disc that create a magnetic field, or flux, in proportion to each other. One coil is proportional to voltage and the other to current. The voltage coil is positioned at 90 degrees to the current coil to produce the flux that acts as a force upon the aluminum disc. This forces it to move in proportion to the product of voltage and current measured in watts. The output is displayed on an odometer-type of cyclometer, where single-digit dials produce numeric readings of wattage over time.

Electronic Meters

• Electronic meters use LCD or LED screens to display readings. These meters can send remote readings to a power company, saving hours in manpower. Electronic meters also provide specific measurements related to energy load and supply as well as determine the amount of power consumed on separate days.

Other Electric Meters

• Electrical power is distributed differently depending on the location and amount of consumption. The connection between a power company and customer is determined by the standard and type of installation. For example, two-wire single phase is standard in Europe, China and India. Split phase is the standard used in North America. The equations used to calculate wattage are different and require different meter constructions. Residential power consumption for a single-family home also differs from multi-family dwellings. Commercial and industrial power consumption requires larger and more intricate metering.

Instruments for Circuit Testing

• Various electrical measurement instruments collect data for testing and examining quality. These tests are used in the construction and maintenance of electrical systems. Instruments such as a voltage meter (or voltmeter) and ohmmeter help determine the proper continuity of an electrical current. A voltage meter (or voltmeter) tests the electrical potential of a circuit and whether the circuit is continuous, therefore working correctly. An ohmmeter tests resistance to ensure that the insulation of circuit wiring is of the highest integrity, which aids proper current flow. A voltmeter is used between two points of an electrical circuit. An ohmmeter creates its own circuit and cannot be used to test existing circuits.