Before installation

  • Make sure that the supply voltage, frequency, and number of phases (single- or three-phase) correspond to the nominal values of the inverter on delivery.
  • A disconnecting switch or similar disconnecting element must be installed between the voltage supply and inverter.
  • Never connect the power supply to the output terminals U, V, or W of the inverter.
  • Do not install any contactors between the inverter and motor. Adhere to a minimum clearance of 100 mm at points where control cables and electric power lines are close to each other, and an angle of 90° for crossing cables.
  • The cables are only protected by slow-blow high-power fuses or a motor circuit breaker. For more information, refer to section Permitted voltage supply systems.
  • Use a 4-core PVC-insulated and shielded cable as the motor cable. Route this cable according to the applicable national regulations of the industry sector and in accordance with the rule set. Use conductor end sleeves to connect the motor cable to the inverter.
  • Make sure that shieldings and sheaths of the motor cable are designed according to the wiring diagram in section General specifications for connection of the motor shield.
  • Make sure that the grounding terminal of each inverter is connected individually and directly to the ground busbar (ground) of the installation site, via a filter if available.
  • Do not loop the ground connections of the inverter from one inverter to the other. Do not route the ground connections to the inverters from other inverters either.
  • The impedance of the ground circuit must comply with the local safety regulations of the industry sector.
  • Make sure that all terminals are tightened with the respective tightening torque, see chapter Permitted tightening torques.
  • To comply with UL regulations, all ground connections must be designed with UL-listed crimp cable lugs.

Unlike direct operation in the supply system, the inverters on the motor generate suitable fast-switching output voltages (PWM). In the case of motors wound for operation with adjustable-speed drives, no further preventive actions are necessary. If, however, the insulation quality is unknown, contact the manufacturer of the motor because preventive actions may be necessary.

INFORMATION

Make sure that the ground connections are properly connected. The inverter can generate leakage currents > 3.5 mA. The grounding cable must be sufficiently dimensioned to carry the maximum fault current of the voltage source that is usually limited by fuses or miniature circuit breakers.
Sufficiently rated fuses or miniature circuit breakers must be integrated into the inverter's power supply in accordance with local laws and/or regulations.