What kind of earth leakage device is suitable for VFD?
ELCB's are not recommended to use in output side of Drive and soft starters, because it may cause nuisance tripping due to PWM output form VFD. However for VFD and soft starter, if the application demands to use of an upstream "residual current device" for protection is required by the installation standards, an A-Si type or Class B type device must be used. If the installation involves several drives or soft starters on the same line, each drive must be earthed separately. If necessary, line chokes needs to be provided as recommended in the catalogue to reduce the leakage current.
ELCB can be used on drive input provided.
1) Residual current device of type B (OR) A-Si type
2) Minimum sensitivity of 300mA.