Shanghai STEP Electric Corporation
Appendix A EMC Installation Guide
A7 Guide for Use of Power line filter
Power line filter may be used by heavy-noise protection devices and noise susceptible devices.
A7.1 Functions of Power line filter
(1) The power line filter is two-way low pass filter which only permits flowing of DC current or
50HZ operating frequency AC current but stops flowing of higher frequency electromagnetic
interference current. Therefore, it can not only inhibit the equipment‘s electromagnetic
interferences flowing into power line but also inhibit the noises in power line flowing into
equipment.
(2) The power line filter may be able to make equipment meeting EMC requirements on
conducted emission and transmission sensitivity. In addition, it may also suppress the radiated
interference of equipment.
A7.2 Precautions for Installation of Power Line Filter
(1) In the cabinet, the filter shall be located close to the power line inlet as practicably as possible.
Additionally, the filter supply line section left in the control cabinet must be as short as possible.
(2) Where the input line and output line of filter is too closely laid, the high-frequency
interference may bypass the filter, couple directly with output line and input line and as a result
make the power filter failing to function.
(3) Usually there is a dedicated ground terminal on the casing of filter. However, if this ground
terminal is connected by a conductor to the cabinet body, the filters will not functions due to the
long conductor with great high-frequency resistance can not plays the role of a bypass. Correct
installation method shall be such: closely laid the filter casing on the conductive plane of metal
cabinet so as to maximize their contact area. Note to remove the insulation coating during
installation in order to ensure good electric contact.
A8 EMC Installation Zoning
In the drive system constituted by elevator integrated drive controller and motor, the elevator
integrated drive controller and peripherals such as control devices and sensors are usually installed
in a same control cabinet. The interferences of control cabinet on external environment may be
inhibited by taking suitable measures at the main contacts, therefore, the supply line radio noise