IEEE Std 2747-2020 pdf free download

IEEE Std 2747-2020 pdf free download.IEEE Guide for Energy Efficiency Technology Evaluation of Electric Power Fittings.
6.6 Test procedures
6.6.1 Test steps
a) The layout of the test circuit should be set up according to 6.4.
b) A test current should then be passed through the test circuit. Consult Annex B for the value of the test current. Another method is to select a certain test temperature in advance. The value and duration of the test current should be such as to raise the reference conductor temperature to the test temperature. When the conductor temperature reaches a steady state, keep constant for 30 mm. Use an initial current value not greater than 1.5 times of the test current to provide accelerated heating to reduce testing time.
c) Measure and record data every five mm in the last 10 mm of steady state, and obtain the results by means of average values of three times measurement. When the energy loss of the fittings is too small to be measured directly, the total energy loss of the fittings and one of its connecting conductors can be measured first betbre the energy loss of the connecting conductors can be measured. Subtract them to obtain energy loss P1 between the voltage measuring points at the two ends of the fitting.
d) Cut oIl the current and pertbrm the next cycle after the conductor temperature cools to within 5 °C above ambient. In order to reduce the cooling time, forced cooling is permitted. However, uniform cooling rate should be maintained in all paris of the test circuit.
e) After the three test cycles, the energy loss of each fitting P, and the energy loss of the reference conductor P1 (P, and P, are both the average of all three cycles) are calculated. The calculation method of the energy loss of fittings P,is shown in Annex A. The relative deviation of each test data from its average may not exceed 5%. Otherwise, the whole process should be resampled and retested.
The energy loss test of fittings should be carried out for three cycles. The test sequence diagrammatic form is shown in Figure 16.IEEE Std 2747-2020 pdf free download.