Hi cove.
Regarding the switching power supply, the voltage after the MAINS rectifier is about 400V DC if input is 240V AC. My question is whether the reference voltage should be 400V DC rather than the 240V AC when determining the insulation between the MAINS parts and accessible parts.
I know many test labs use the reference voltage of 240V AC as always they did. Reason from one German NB is that the test values for the barrier based on primary transients up to 6kV. Compared to that difference between 400V DC and 240V AC is negligible. This explanation seems strange and differents from IEC 60664 a little bit.
Please kindly share your experience. Thanks and regards.
Roland
Regarding the switching power supply, the voltage after the MAINS rectifier is about 400V DC if input is 240V AC. My question is whether the reference voltage should be 400V DC rather than the 240V AC when determining the insulation between the MAINS parts and accessible parts.
I know many test labs use the reference voltage of 240V AC as always they did. Reason from one German NB is that the test values for the barrier based on primary transients up to 6kV. Compared to that difference between 400V DC and 240V AC is negligible. This explanation seems strange and differents from IEC 60664 a little bit.
Please kindly share your experience. Thanks and regards.
Roland