cupoftea
Advanced Member level 5
Hi,
We have seen a 500W Offline PSU using a TUNS500F ACDC module with a Cosel Mains filter upstream of it (NBC-10-102).
The mains input cable (L,N & E) comes in, and live and neutral obviously go to L and N connections of the filter. However, the Earth wire is first taken to a chassis screw connection some 10cm away from the filter input "E" connection.....then, another chassis earth connection, on the downstream side of the filter, finally brings the earth wire connection to the filter input. Would you agree that this is going to worsen common mode EMC?....
....Surely the incoming earth wire should go straight to the filter input "E" terminal...then another ring terminal on the "E" terminal should take earth to chassis?
TUNS500F ACDC module
NBC-10-102 mains filter
We have seen a 500W Offline PSU using a TUNS500F ACDC module with a Cosel Mains filter upstream of it (NBC-10-102).
The mains input cable (L,N & E) comes in, and live and neutral obviously go to L and N connections of the filter. However, the Earth wire is first taken to a chassis screw connection some 10cm away from the filter input "E" connection.....then, another chassis earth connection, on the downstream side of the filter, finally brings the earth wire connection to the filter input. Would you agree that this is going to worsen common mode EMC?....
....Surely the incoming earth wire should go straight to the filter input "E" terminal...then another ring terminal on the "E" terminal should take earth to chassis?
TUNS500F ACDC module
NBC-10-102 mains filter