VFD long cable length
With respect to longer cable lengths, there are two concerns.
1) Reflected wave effect - Depends on Motor CIV (corona Inception Voltage) and cable length distance. Mere putting RC circuit may not help and can burn motor outer layer winding due to voltage spikes during operation in case of VSI drives. Some VFD vendors have dedicated simulation software available which can help get right solution with above mentioned inputs. Simulation Software can also show the voltage spike trends at drive output and motor input to make sure that motor is safe with the solution voltage spikes are below motor CIV value all time.
2) Voltage drop in longer cable - It depends on cable length, cable size and application also to see impact of voltage drop and current demand by load to meet torque requirements. By right cable size selection and utilizing simulation software, right solution can be generated.
It needs better engineering rather than mere product selection to ensure safe and longer operations.
1) Reflected wave effect - Depends on Motor CIV (corona Inception Voltage) and cable length distance. Mere putting RC circuit may not help and can burn motor outer layer winding due to voltage spikes during operation in case of VSI drives. Some VFD vendors have dedicated simulation software available which can help get right solution with above mentioned inputs. Simulation Software can also show the voltage spike trends at drive output and motor input to make sure that motor is safe with the solution voltage spikes are below motor CIV value all time.
2) Voltage drop in longer cable - It depends on cable length, cable size and application also to see impact of voltage drop and current demand by load to meet torque requirements. By right cable size selection and utilizing simulation software, right solution can be generated.
It needs better engineering rather than mere product selection to ensure safe and longer operations.
