There is an issue with power supply efficiency (counted value is 88%, real value is near 80%)
This is non-diming scheme, with LNK 409 in spite of LNK419, with R6=49,9k. D5 is replaced on 1N5408, VR1 is 1.5KE200A.
Scheme works correctly and stable, but the transformer heats to 75-80 Celsius degrees, the other elements don't heat significantly.
Please advise possible ways of efficiency improvement.
Scheme file is attached.
In : 235V 0,166А PF0.97
Out: 74,3V 0,42А
transformer: L=1512 uH, Lleakage= 35.8uH
Thanks & Regards.