Continuously transposed conductor (CTC) is a type of winding wires weaved by certain number of strips of enameled rectangular wires in two ranks according to special technics and wrapped by special insulation material. It is mainly used for large-scale oil-immersed power transformers, reactors and large-capacity dry type transformers.

CTC can improve using rate of winding space, minish volume and reduce cost, most of all, it decline the loss of circumfluence and eddy loss caused by leaking of magnetic field and also has advantages of improving machine strength of winding and saving winding time.

Manufacture range:

Number of strips: 5_36 single dimension: Thickness of conductor a: 1.00mm_3.15mm width of conductor b: 3.00mm_12.50mmsuggested ratio of width and thickness: 2.5Insulation layers: 24 layers at one time. Max thickness of CTC: 80mm (excluding insulation) max width: 26mm (excluding insulation)

Material: Single conductor:

Polyvinyl acetal enameled rectangular copper wire, class 120, 155
PVA+epoxy enameled rectangular copper wire, class 120
Poly esterimide(epoxy) enameled rectangular copper wire, class 180
Choose thin insulation increase (0.08mm-0.11mm) or thick one (0.12mm-0.16mm) according to requirements of different electric insulation, and thickness of epoxy is about 0.03mm-0.05mm of thermal enameled rectangular wires. We use medium wearing instument to enamel which makes solidify of increase nearly perfect. Please connect us if there is special requirement of increase or choose other enameled wire.
Soft copper used for enameled rectangular wires applies for GB5584.2-85 and suggested strength proof (RP0.2)as following according to different machine strength:
C1 RP0.2>100_180N/mm2
C2 RP0.2>180_220N/mm2
C3 RP0.2>220_260N/mm2

Wrapping paper:

Kraft, high density paper, denission, Nomex, polyester cloth, polyester fibre net bonding strand.
Please connect us if choose other insulation paper.
Structure design and dimension calculation
Pitch: Distance between two consecutive transposed units of CTC.
Pitch of CTC is depends on the Min diameter of winding and number of strips and calculation formular as below:
S=d× η /n
S----pitch
D----The Min diameter of winding
N---number of strips
Generally, pitch is about 10_14 times of width of conductor and it can even be 6_7 times sometimes. Please inform us if there is special requirements of pitch.
Intercolumn paper: Paper with certain thickness between two rank of strips of CTC used for improving axial compressive strength of CTC. Suggested thickness of intercolumn is about 0.13mm. Generally, there can be no intercolumn if (n-1)/2× A<10mm, of which A means thickness of single conductor.

Overall dimension:

Simple calculated formular of dimension of CTC:
Thickness: H=1/2(n-1)A+Δ
Width: W=2B+Δ
Of which, A means thickness of single conductor
B means width of single conductor
Δ Means width of insulation paper

Order information:

Please pay attention to following points when order CTC:
1. Number and nominal dimension of single conductor
2. Type and increase of enameled wires
3. Type of insulation paper and intercolumn
4. Thickness of wrapped paper
5. The Min diameter of winding
6. Number of reels of CTC
7. Length of each reel and dimension of reel.