While disassembling the power for the spindle of my hobby CNC mill, I came across something peculiar which I think warrants a question on this site.
The input is standard 220V AC.
- Phase 1 (brown) from source is fed directly to spindle phase 1.
- Neutral (blue) from source is fed to transformer primary coil in.
- Transformer primary coil out is fed to spindle neutral.
Please see photos below.
- Gray cable to right is source
- Black cable to left is spindle
- Bottom gray cable is transformer
- Only connectors for primary stage on this side
- Name of this transformer is "drossel", which according to google means "throttle"
- No connectors here (or anywhere else for that matter)
So it appears that the transformer has only a primary coil and no secondary. In other words, it is functionally equivalent to a giant coil.
My question is, what purpose does this transformer serve?
My naive guess as a novice is that it is used as some kind of filter or storage, like a capacitor.
Any hints are welcome!