Arctic Materials

Technical Data Sheet

Arcwire PA 220 Corona Resistant Polyamide-imide Overcoat

Filled polyamide-imide overcoat for class 220 R dual coat wire on inverter-fed windings and hermetic compressor motors. The dispersed inorganic filler slows erosion of the film by repetitive partial discharge in the air gaps between turns.

Grade Arcwire PA 220  |  Range Electrical Insulation and Wire Enamels  |  Technology Polyamide-imide resin with dispersed inorganic filler, in organic solvent

Arctic Materials

Technical Data Sheet
Arcwire PA 220
Issue 2026.09

1. Product description

A polyamide-imide overcoat carrying a dispersed inorganic filler, for class 220 R wire on inverter-fed windings and on hermetic compressor motors. The filler slows the erosion of the organic film by repetitive partial discharge in the small air gaps between turns, which is the mechanism that ends the life of an ordinary enamel on fast-rising pulse duty rather than a single breakdown event. The same chemistry gives the refrigerant and hydrolysis resistance that sealed refrigeration and air-conditioning windings are specified against, and the resin is formulated to hold the filler dispersed through the line.

2. Features

  • Inorganic filler slows partial discharge erosion on fast-rising pulse duty
  • Refrigerant and hydrolysis resistance for sealed refrigeration and air-conditioning windings
  • Class 220 R as a dual coat system
  • Resin formulated to hold the filler dispersed through the line
  • Converter-fed endurance is qualified on the insulation system as built

3. Recommended uses

Winding wire for inverter-fed motors, and for hermetic compressor motors in refrigeration and air-conditioning equipment.

Substrates. Cured polyesterimide or polyimide base enamel on round or rectangular copper or aluminium conductor.

4. Typical properties

PropertyTypical valueMethod
TechnologyPolyamide-imide resin with dispersed inorganic filler, in organic solventFormulation
AppearanceOpaque filled liquid; the filler settles on standingVisual inspection
Non-volatile matter, including filler28 to 38 per cent by weightISO 3251
Thermal class of the material220 R as a dual coat systemIEC 60085 for the designation; thermal endurance to IEC 60216-1
Temperature index, dual coat wire220 to 230 at the 20 000 h reference for the dual coat construction suppliedIEC 60172
Breakdown voltage, twisted pair at ambient temperature3.5 to 11 kV on grade 2 wire, rising with conductor diameter and buildIEC 60851-5
Cut-through, softening under load320 °C to 370 °C, 100 K to 150 K above the rated thermal classIEC 60851-6
Heat shockNo cracking after 30 min at 240 °C (class temperature plus 20 K), wound on a mandrel of 1 to 5 times the conductor diameterIEC 60851-6
Resistance to solvents and to refrigerantsNo film softening, blistering or loss of adhesion after the specified exposure and reheatingIEC 60851-4
Resistance to repetitive partial dischargeAssessed on the wire against the agreed pulse conditions; converter-fed endurance qualified on the machine insulation system as builtCustomer or supplier protocol for the wire; IEC 60034-18-41 for the system

Typical values, not a specification. Values for each batch are given on its Certificate of Analysis.

5. Application

ParameterGuidance
MethodLast three to five passes on the enamelling line over a cured base, die or felt application
SubstrateCured polyesterimide or polyimide base enamel on round or rectangular copper or aluminium conductor
Filler suspensionRoll or stir the container until uniform, and keep agitated circulation in the applicator throughout the run
Viscosity adjustmentAdjust only with the thinner specified for the grade, to suit die or felt application
CureOven cured in sequence with the base; base cured enough to carry the topcoat and not so far that the layers fail to bond
Specification inputsDC link voltage, pulse rise time and switching frequency agreed before the grade is fixed
TerminationsNot directly solderable: terminations are stripped, welded or crimped

Process. Applied as the last three to five passes on the enamelling line over a cured base, with agitated circulation in the applicator to keep the filler in suspension. Oven cured in sequence. Thermal class 220 R as a dual coat system. Corona resistance is a property of the wire, while converter-fed endurance is qualified on the insulation system as built.

6. Storage and handling

Store in the original closed containers indoors, in a dry place away from direct heat and frost; the filler settles on standing, so roll or stir until uniform before use. Shelf life is stated on the label and Certificate of Analysis. Handle and use the product in line with its Safety Data Sheet.

7. Safety and regulatory information

Read the Safety Data Sheet before use. Safety Data Sheets and regulatory declarations are issued by our technical centre against the product and batch supplied, so they are sent on request rather than published. Request a Safety Data Sheet or declaration.

This Technical Data Sheet is published for on-screen reference. The information is given in good faith from laboratory and application experience and describes typical values; it is not a specification and does not replace a trial on your own substrate and line. Arctic Materials may revise this sheet without notice. Issue 2026.09.

Technical Data Sheets on this site are for on-screen viewing. For a controlled copy, write to tech@arcticmaterials.com.