Automated Transformer Temperature Rise Tester
Original Publication Date: 1979-Nov-01
Included in the Prior Art Database: 2005-Feb-20
This system provides an automated transformer temperature rise tester. The tester measures the change in resistance in as many as 10 windings with respect to time under program control and computes the temperature rise for each winding. The system uses 20 data points for each winding and does a least sum of the squares fit on a semilog scale. From this best fit line, the intercept corresponding to time equal to zero is extracted, which is the hot resistance due to internal power loss. The equation used in the software to compute temperature rise is: (Image Omitted) where Rh = hot resistance Rc = cold resistance TA1 = room ambient temperature at start of test TA2 = room ambient temperature at end of test K = 234.