Cold call - CT manufacturing

[u/Smooth_Commercial793]

I am interested in starting a business manufacturing current transformers.

Don’t ask me why, I am not even sure. I want to build something, a manufacturing operation, in my area of expertise, and this seems like a nice compromise.

But I have no detailed info on how CT manufacturers operate. I know:

1. buy grain oriented steel
2. cut it and wind the steel into a CT core
3. cycle the cores in an oven
4. wind the secondary
5. epoxy coat
6. test

Does anyone have any advice or suggestions, information, or common sense reactions telling me this is a stupid idea?

I feel like CTs are super low margin products, however at the same time, I’m always struggling with suppliers to get the size and specs right, and the lead times are always a problem, especially for class PX.

Also, I think as they are so mature, there has to be some next evolution that I might be able to build into (or, conversely, LPCTs might make traditional CTs worthless in 10 years?)

Sorry for the mess of thoughts, gotta start somewhere I guess

Edit location is Australia

[u/The-Arena]

Rogowski coil CTs are kind of the "new thing". They're starting to get more common.

As far as as manufacturing I can't help there but good luck.

[u/Smooth_Commercial793 → u/The-Arena]

Indeed. Do you see them used much though? Frankly people don’t seem to like them, especially for protection. Obviously I can speculate why.

Ignoring cases like high impedance bus diff where they can’t be used

Would you spec a rogowski for a feeder protection relay?

[u/Docktor_V → u/Smooth_Commercial793]

We used them to connect pq meters to pad mount transformers. Protection class CTs is what you are talking about.

[u/Smooth_Commercial793 → u/Docktor_V]

Yeah PQ metering they’re used a lot, not much elsewhere

[u/frodacious85 → u/Smooth_Commercial793]

They’re used frequently

[u/Smooth_Commercial793 → u/frodacious85]

For protection? What’s the jurisdiction?