Residual current breaker trips with frequency inverter.

[Karsten]

Hi,

I have a problem with a "mobile" equipment with a frequency inverter. The equipment trips the residual current breaker. I have bee reading a little. By disconnecting the EMC filter it seems to work but I do really not want to do that.

Ideas??

 

[rQx]

It's normal since the filter leak to ground. If you disconnect the filter you will introduce interference on the line.

 

[rQx]

Do you need a 30mA RCD? You can try 100mA or 300mA if you dont have a demand for 30mA

 

[the_msp]

I had issues with 2 VFD's (two different brands) tripping a 30mA RCD. Moving to a higher mA RCD wasn't an option so it was cured by adding an isolation transformer.

 

[AustralIan]

Where did you put the isolation transformer?

 

[the_msp]

It was portable equipment, so, between the 3 pin socket and equipment 3 pin plug. Looked like a "tradie's" 110V transformer for site work, only it was 230->230V not step down. Like this only 3KVA.

 

[goghie]

There are RCDs which can solve problem . When it comes to Eaton (ex Moeller) and Schrack products they have -U at the end of product type name.

 

[AustralIan]

If an isolation transformer is downstream of an RCD, then
anything downstream of the transformer is no longer RCD protected. You would have to put in another RCD downstream of the isolation transformer if the situation needs RCD protection.