-
Provide a good high frequency connection between the motor and the frequency converter for instance by screened cable which has
a 360° connection in the motor and the frequency converter
-
Provide a low impedance path from frequency converter to building ground/earth and from the motor to building ground/earth. This
can be difficult for pumps
-
Make a direct earth connection between the motor and load machine
-
Reinforce the PE so the high frequency impedance is lower in the PE
-
Ensure the motor and load motor are aligned
3.
Lower the IGBT switching frequency
4.
Modify the inverter waveform, 60° AVM vs. SFAVM
5.
Install a shaft grounding system or use an isolating coupling between motor and load
6.
Apply conductive lubrication
7.
If the application allows, avoid running at low motor speeds by using the minimum speed settings of the drive .
8.
Try to ensure the line voltage is balanced to ground. This can be difficult for IT, TT, TN-CS or Grounded leg systems
9.
Use a dU/dt or sinus filter
3.6.20 Control cable routing
Tie down all control wires to the designated control cable routing as
shown in the picture. Remember to connect the shields in a proper way
to ensure optimum electrical immunity.
Fieldbus connection
Connections are made to the relevant options on the control card. For
details see the relevant fieldbus instruction. The cable must be placed to
the left inside the frequency converter and tied down together with other
control wires (see picture).
Illustration 3.51: Wire path for control wiring.
VLT AQUA High Power Operation Instructions
3 How to Install
MG.20.P3.02 - VLT
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