Switching power supply routine test items
I. Purpose.
To test whether the S.M.P.S. energy efficiency value meets the requirements of the corresponding national energy efficiency rating standards (specifications are defined according to the requirements of the national standards).
II. Apparatus and equipment to be used.
(1). AC SOURCE / alternating current power supply.
(2). ELECTRONIC LOAD / Electronic Load.
(3). AC POWER METER / power meter.
III. Test Conditions.
(1). Input voltage conditions are 115Vac/60Hz and 230Vac/50Hz with 220Vac/50Hz/60Hz conditions.
(2). Output load conditions are no load, 1/4 max. load, 2/4 max. load, 3/4 max. load, and max. load.
Test Methods
(1). Warm up the product under its nominal output load condition for 30 minutes before testing.
(2). Record the input power (Pin), input current (Iin), output voltage (Vo), and power factor (PF) of 115Vac/60Hz and 230Vac/50Hz respectively in descending order of load.
Then calculate the efficiency of each conditional load.
(3). At no load only the input power (Pin) and input current (Iin) are to be recorded.
(4). Calculate the average efficiency of the four loads at 115Vac/60Hz and 230Vac/50Hz, which is the efficiency value of energy efficiency.
V. Standard Definitions.
CEC / U.S.A. EPA / Australia and New Zealand Energy Efficiency Specification Value Standard (Class IV);
(1). The specifications of Class IV efficiency are: 1).Po<1W, Average Eff. ≥0.5*Po; 2).1≤Po≤51W, Average Eff. ≥0.09*Po; 3).1≤Po≤51W, Average Eff. ≥0.09*Po; 4).
Average Eff. ≥0.09*Ln(Po)+0.5; 3).Po>51,Average Eff. ≥0.85.
(2). The input no-load power specification is:1).0
(3). Po is the product of the rated output voltage and rated output current as indicated on the nameplate.
(4) . The average efficiency value and input no-load power value of the actual test need to meet the specifications at the same time to meet the standard requirements.
Sixth, calculation method examples:
(1). 12V/1A energy efficiency = (0.09*ln12+0.5 )*100% = (0.09*2.4849+0.5)*100% = 72.36%;.
(2). Input power ≤ 0.5W.
