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SynWire – Winding Wires

SynWire type 155, Copper Wire, round, enamelled, self bonding

  • enamelled round copper wire, self-bonding
  • insulated with solderable polyurethane
  • aliphatic polyamide
  • class 155

The SynWire type 155 is a thermal class F enamelled copper wire which can be directly soldered and self bonded under heat. With a solder bath temperature from  390 °C the wire is solderable without prior removal of the insulation film.

The SynWire type 155 is a 2-ply self bonding wire which is used to produce thermally stimulated windings in an integral and thus space saving, machine suitable, efficient and cost-effective manner. In contrast to impregnants, these windings can be bonded quickly and environmentally friendly. The self bonding windings are characterised by their thermal and mechanical stability. State-of-the-art processing techniques, process controls and checks ensure the constant high quality of these wires.


Electric motors, solenoid coils, stator windings, air coils


IEC / DIN EN 60317-35
IEC / DIN EN 60317-0-1
UL approved

Delivery forms

Grade 1B + 2B: 0.036 – 1.25 mm

Technical data

Typical properties of enamelled round self-bonding copper wire, 0.500 mm, with insulation film grade 1B

Outer diameter with varnish  Adhesion and elongation  Elongation at break  Adhesiveness at r.t.  Blank wire diameter 
Unit of measure Set value  Actual value (typ.) 
mm  min. 0.541 - max. 0.568 as set value
  1 x d, no cracks 1 x d / 10 % pre-elongation
≥ 28 42
> 1.1 ≥ 3
µm  0.495-0.505 as set value
Temperature index TI  Softening temperature, tested  Re-softening temperature  Heat shock at 175  Solderability at 390 °C  Bonding temperature 
Unit of measure Set value  Actual value (typ.) 
°C  min. 155 160
°C  ≥ 200 ≥ 2 Min. at 200
°C  160 ≥ 160
°C  mandrel diameter 1.120 mm ≥ 175
≤ 6 ≤ 4
°C  200 ± 2 200 ± 2
Dielectric strength RT  Electric conductivity 
Unit of measure Set value  Actual value (typ.) 
kV  ≥ 2.4 (twist) ≥ 2.4
m/Ωmm²  58-59 58.5