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ADDITIONAL PRECAUTIONS TO LIMIT EMI AND RFI
Earth
For T-verters:
In any single low-impedance earth point or where busbar is required in order to put to earth
directly or independently for varied circuit. The T-verter itself must be put to earth
independently. No other equipment should share the earth connection of the T-verter
(except the motor). All circuits have to be connected to external earth through copper bars.
Note: The system needs to be checked from time to time to ensure well connection to earth
ground
For Induction Motors:
For electrical safety reasons, motors must connect to earth ground with a cable even if the
motor is fixed on a metal plate. The best way is to use green line 4-core motor cable to
connect between the frame of the motor and the earth ground of the T-verter. Please avoid
putting the motor to earth ground via busbar.
For Control Circuit:
If the control circuit of T-verter links to any control switches, relays or other similar
equipment, be sure the screened control line is put to earth ground on only one end.
For Shielding System:
In order to have a very low HF-impedance shielded cable with, a metal clamp and special
adapters are required and the paint on the surface of metal has to be removed.
Shielding:
2.1 The T-verter will emit EMI noise via the connection cable; therefore, all motor cables,
control cables and signal cables must be shielded unless the length of the cable is less than 1
meter.
2.2 The shielded motor cable must be put to the earth ground on both ends, the shorter the cable
the better to reduce the stray inductance and capacitance effect.
