Unrestricted     83                   A5E43486667A_AB 
   CAUTION: If the operation of the motor with a variable frequency 
drive  (VFD)  is  necessary,  the  readings  listed  in  the  standard  NEMA-MG1 
Section 4 Part 31, or in the NEMA MG2-Section 6 must be addressed. In 
addition:  
 
1.  Variable frequency drive must be properly selected, according to the 
power of the motor and the conditions of the electrical supply (such 
as number of phases, voltage, and current capacity). 
2.  Connect the motor, the VFD, metal conduit and any metal part to an 
independent grounding circuit. The VFD must be mounted as close 
as possible to the motor. 
3.  Use  conductor  with  the  appropriate  gauge,  the  shortest  possible 
length  and  canalized  through  metal  conduits.  In  addition  the 
conductors can be shielded to reduce electromagnetic interference 
with electronic equipment. 
4.  The  operation  of  a  motor  with  a  VFD  causes  an  increase  in 
operating temperature which in turn leads to the deterioration of the 
insulation on the windings. 
 
 WARNING:  Always  attend  the  safety  instructions  of  the  VFD 
manufacturer. High AC and DC voltages are present in a VFD even after the 
VFD is de-energized. See VFD operation manual to avoid personnel injury.  
In order not to affect the optimal functioning of the motor-VFD system and to 
ensure proper insulation; the length of the power leads from the VFD to the 
motor  shall  not  exceed  those  listed  in  Table  1.1.  Maximum  power  leads 
length from VFD output to motor. 
 
 
 
 
 
 
 
 
 
Table 1.1 Maximum power lead length from VFD output to motor.