13
 
 
External wiring should be carried out in accordance with following requirement. Check and reassure the 
wiring is correct after the wiring is complete.  
(Do not utilize the control circuitry buzzer to check the wiring.) 
 
 
EMI connections: 
 
It is very important that the connections between the inverter, the shielded motor cable, and the EMI 
filters are tested as follows. 
 
z  Use a metal grounding plate and place the frequency inverter and the EMI filter on the plate. 
z  Use a shielded motor cable with 4 connectors (U, V, W, & Earth), don’t use the shielding as safety 
earth (shield is high frequency earth) 
z  Remove any paint around the two metal coupling nut holes. So that the metal coupling nuts (and 
the shielding) make contact with the frequency inverter and the motor. 
z  Don't solder a conductor to the shielding. 
z  Use a metal clamp to connect the shielding from the motor cable with the metal grounding plate. 
Now there is a perfect high frequency earth connection between frequency inverter, grounding 
plate and EMI filter. 
z  Keep the distance between the frequency inverter and EMI filter as short as possible (< 30cm) if 
longer use a shielded cable with a metal coupling nut and a metal clamp to connect the shielded 
cable to the frequency inverter and metal grounding plate. 
z  The only earth connection between the LISN and the test plate should be via the EMI filter. 
z  Use a motor which equals the power rating or below of the inverter rating.      
 
z  Install a noise filter for inverter onto the output side of the primary circuitry can suppress 
conducting noise.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Remote control switches, 
relay or similar equipm ents
Power Supply 
Power Drive System(PDS) 
Metal plate or panel 
EMI FILTER 
Power Port 
Main Transform er 
3ΦIM 
M
L
NN
LL1
L2
TM2
T1
T2
T3
U 
V 
W 
G 
MC C B
Drive 
Class B: