How can I disconnect the EMC filter (RFI) on an ATV21?

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Observation

An installation incorporating an ATV21 drive may experience the following anomalies:

The circuit-breaker on the incoming supply trips for non-IT neutral point connections.
The insulation control relay detects an initial fault for IT neutral point connections.

Cause

This is a side-effect of EMC filter type protection devices installed to counter the radio interference emitted by a drive.

Solution

If you are using the ATV21 drive on a system with an isolated or impedance earthed neutral, use a permanent insulation monitor which is compatible with non-linear loads.

ATV21 drives with a nominal value of 480 V have built-in radio frequency interference (RFI) filters with earthed capacitors. If you are using the drive on an impedance earthed system, we recommend that you isolate the RFI filters from earth so as not to shorten their operating life.

Note: In case of three phase 400V, 5.5kW or less model, if you disconnect the capacitor from ground,

set the parameter of carrier frequency f300 to 6kHz with motor cable length 30m or less.

ATV21H 075N4 to U55N4, ATV21H D22N4 to D30N4

Pull the jumper towards the left of the earth terminal as shown below, which will isolate the RFI filters.

ATV21H U75N4 to D18N4

Connect the cable to the power terminal at the top left as shown below, which will isolate the filters.
ATV21 TERMINAL LAYOUT 2

By removing these filters you may cause interference on any electronic equipment in the area

General note regarding the ATV range:

The option to disconnect the RFI filter is available for:

Current ranges: ATV212 , ATV12, ATV320,ATV340, ATV600 and ATV900 series
Obsolete ranges:ATV21, ATV28,ATV31,ATV312, ATV38, ATV58 ,ATV61 and ATV71.

Caution: This option is not available for ATV11 drives.