View Single Post
Old 10th Dec 2021, 8:05 pm   #18
kalee20
Dekatron
 
Join Date: Feb 2007
Location: Lynton, N. Devon, UK.
Posts: 7,080
Default Re: Early Unusual Transformer Design

If you connect the transformer to a variable supply (with a voltmeter across the supply to be sure you're hitting it with full voltage) via a wattmeter, leaving the secondary completely open-circuit, the power drawn is virtuall all core (iron) losses. (The primary current is relatively low, and secondary currents are zero, so winding losses are negligible).

Then if you dump the voltmeter in parallel, but put an ammeter in series, and this time short-circuit the secondary, wind up the input till you see the normal loaded primary current drawn. This time the voltage is low, so the magnetism in the core is low and iron losses will be negligible. The figure on your wattmeter thus will be copper losses.

Add the two figures together to get total losses at full voltage and full load.
kalee20 is online now