Danfoss autopsy

They sound like inductors. I'll bet that the cores consist of a stack of Es and a stack of Is separated by a thin spacer, rather than interleaved Es and Is the way transformers are made.

Thanks for the reply John. Pardon my ignorance, But what purpose would these serve? P.S. This is a VLT 5000 series BTW.

I can only guess, but inductance limits the rate of rise of current when a voltage is switched on. This effect can be used as a way to figure out that the motor leads are shorted and switch back off before the short produces damaging current levels, or as high frequency noise filter components. If being used in the motor circuit, I would have expected 3 of them. With only two, they are more likely part of the supply noise filter. Is this drive powered by single phase or 3 phase?

Either they are chokes or there is also one large wire going through each.

These are wound with what appears to be 16 to 14 gauge.

Do you have a model number?

Does it look like any of these?

these?

Yes its the vlt 5000 series.

Unfortunately, this data sheet does not have a schematic, but includes lots of info about the general concept of the drive:

Can you trace if these two inductors are part of the DC filter between the 3 phase rectifier and the storage capacitors?

Pretty much chokes then.

1. Intermediate circuit coils

Smooths the intermediate circuit current and limits the load on AC line and components (AC line transformer, wires, fuses and contactors).

They are DC line reactors. There is one placed in the (-) and one placed in the (+) leg between the 3 phase input full wave bridge rectifier and the capacitor bank. They are used for harmonic control. External input line reactors are not needed.

Jeff