ANTIQUE QUEEN & CO ELECTRODYNAMOMETER, ELECTRIC METER RARE - MUSEUM QUALITY - EARLY ELECTRICAL APPARATUS Start Price USD 899.99 Current Price USD 899.99 Time Left - Bid Count 0 Buy It Now Price - Reserve Price - Start Time Sunday, November 16, 2008 End Time Sunday, November 23, 2008 Location Hudson, Wisconsin See more about 'ANTIQUE QUEEN & CO ELECTRODYNAMOMETER, ELECTRIC METER' Description ANTIQUE ELECTRODYNAMOMETER   Up for your consideration is an early Electrodynomometer.  It is marked "QUEEN & CO, MAKER, PHILA." It measures a little over 16 inches tall annd weighs about 7 pounds. This is an incredible looking  and high quality instrument with heavy hand turned brass pieces,  adjustable brass legs, brass screws, copper tubing and beautiful woodwork.  As you can see in the pictures it is in pristine condition.  It just needs a little detail cleaning and it looks virtually new.   It is my understanding that these are very rare and this one is probably the best example a you will find.     I will be listing several other early interesting pieces of electrical apparatus.  Including an early James Biddle variable resistor and others.  Please take a look!   Below is more information on these and also a link to a page from Kenyon University in Ohio that has information and photos.      http://physics.kenyon.edu/EarlyApparatus/Titlepage/Electrical_Measurements.html    An electrodynamometer is an instrument used for measuring the electric power. The basic principle was laid out in an 1848 paper by Wilhelm Weber (1804-1891): when the same current passes through two concentric coils placed at right angles to each other, the resulting torque depends on the square of the current.     The electrical inventor and entrepreneur, Werner von Siemens (1816-1892), used this principle in his electrodynamometer, first described in 1880. In order to measure thepower dissipated in an electrical load, it is necessary to measure the current through the load and the potential drop across it. In the Siemens instrument, the stationary coil is made of relatively few turns of heavy wire and is connected in series with the circuit. The rotating coil consists of many turns of fine wire, and is connected across the load with a multiplier resistance in series with it to measure the potential drop.  The currents through the two coils are I and a current proportional to V, and the product of the two currents is proportional to the power dissipated in the load.            Powered by eBay Turbo Lister The free listing tool. List your items fast and easy and manage your active items. On Nov-05-08 at 15:34:05 PST, seller added the following information:   Place a Bid!