Copper Continuously Transposed Cables (Cu-CTC)
Advanced CTC solutions for power and traction transformers, designed for improved winding space factor, lower copper losses and enhanced mechanical strength. The CTC brochure states that CTC is primarily used in power and traction transformers, and offers advantages including improved winding space factor, reduced total copper losses and enhanced mechanical strength for short-circuit withstand conditions.
Overview
Continuously Transposed Cable consists of a number of rectangular, film-insulated conductors assembled together and usually overwrapped with insulation paper. The construction is designed to optimise transformer winding performance while maintaining dimensional and electrical reliability.
Key Features
- CTC up to 96 conductors
- Multiple CTC manufacturing lines
- Film-insulated rectangular strands
- Paper over-wrapped construction
- Epoxy bonded transposed cable options
- SCCNET CTC with or without paper insulation
- Diamond wrap and perforated paper options
- Custom drum supply as per customer winding machine requirement
Technical Specification
| Parameter | Capability |
|---|---|
| Individual strand material | Soft ETP Copper |
| Minimum strands | 5 |
| Maximum strands | 95 / CTC up to 96 conductors |
| Strand thickness | 1.00 mm to 5.00 mm |
| Strand width | 2.80 mm to 13.00 mm |
| Width/thickness ratio | 1.5:1 to 6.5:1 |
| Transposed cable height | 5.00 mm to 100.00 mm |
| Transposed cable width | 6.00 mm to 30.00 mm |
| Material content | Cu + Ag > 99.9% |
| Resistivity at 20°C | ≤ 0.01724 Ω mm²/m |
CTC Variants
1. Standard Paper Wrapped CTC
For transformer winding applications requiring conventional paper insulation and reliable winding performance.
2. Epoxy Bonded Transposed Cable
Epoxy bonded transposed cable provides very high mechanical strength and helps windings withstand high electro-dynamic forces during short-circuit conditions.
3. SCCNET CTC
SCCNET CTC is a special transposed cable with or without paper insulation, wrapped with transformer oil-resistant polyester monofilament and supplied with protection paper that is removed before winding.
4. Diamond Wrap CTC
Diamond wrap uses opposing wraps of aramide paper to allow free oil flow through CTC strands for cooling purposes.
5. Perforated Paper CTC
Perforated paper CTC is designed for excellent heat dissipation and is suitable for epoxy application with radial or concentric bond.
“Our CTC solutions are engineered to improve transformer winding efficiency, mechanical strength and thermal performance.”
