Hi, As you know , in an offline SMPS supplied by L,N & E, the Y capacitors would go from
L and N to earth. They can be placed either upstream or downstream of the
common mode choke. Is the following right?..
(please assume that in all cases there is alreasy a Y capacitor across the isolation transformer, from quiet node(primary) to
quiet node(secondary)
1)..Placing the Y capacitors upstream of the common mode choke (CMC) is best to give immunity of the SMPS (and whatever it supplies)
2)...Placing the Y capacitors downstream of the CMC is best to get a conducted EMC pass of the SMPS?
3)...If you only have room for one Y capacitor, then where would you place it?...presumably after the diode bridge to either
HVDC+ or HVDC-, because in that case, it would alternatively connect to L and N , every alternate 10ms?
L and N to earth. They can be placed either upstream or downstream of the
common mode choke. Is the following right?..
(please assume that in all cases there is alreasy a Y capacitor across the isolation transformer, from quiet node(primary) to
quiet node(secondary)
1)..Placing the Y capacitors upstream of the common mode choke (CMC) is best to give immunity of the SMPS (and whatever it supplies)
2)...Placing the Y capacitors downstream of the CMC is best to get a conducted EMC pass of the SMPS?
3)...If you only have room for one Y capacitor, then where would you place it?...presumably after the diode bridge to either
HVDC+ or HVDC-, because in that case, it would alternatively connect to L and N , every alternate 10ms?