Polyesterimide Series

QZY / Q(ZY/XY) Enameled WireEngineered for Extreme Environments

180–220°C thermal ratings with exceptional chemical resistance and thermal shock performance.

YIDA's Polyesterimide Series is engineered for the most demanding electrical applications — from high-temperature industrial motors to aerospace and nuclear environments. The base QZY (EIW) grade provides Class H 180°C performance, while the composite Q(ZY/XY) (EI-AIW) adds a Polyamide-imide topcoat for 200–220°C operation and superior mechanical protection.

The dual-layer composite construction delivers outstanding resistance to thermal shock, chemical exposure, and radiation — making it the preferred choice for applications where standard enameled wire cannot meet the environmental demands. Available in diameters from 0.06mm to 3.0mm across all thermal classes.

Temperature Versatility

Performs reliably from extreme heat to sub-zero conditions across diverse operating environments.

Thermal Shock Resistance

Endures sudden temperature swings without loss of mechanical strength or electrical integrity.

Chemical Resistance

High resilience against solvents, varnishes, and aggressive chemical environments.

Radiation Resistance

Engineered for aerospace, medical devices, nuclear facilities, and high-radiation zones.

Direct factory pricing and decades of manufacturing expertise ensure premium quality at competitive rates. YIDA's Polyesterimide Series is backed by rigorous quality control and full compliance documentation for IEC, GB/T, and NEMA standards.

YIDA Polyesterimide enameled wire product

YIDA Enameled Copper Wire Insulation Guide

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Technical Specifications

Polyesterimide Series Specifications

Single-layer EIW and composite EI-AIW — covering 180°C to 220°C thermal classes.

Polyester-imide — QZY (EIW)

Thermal Class	Insulation Type	YIDA Product Code	Diameter Range (mm)	Diameter Range (AWG)	IEC Standard (60317)	GB/T (6109)	NEMA Standard
180°C	Polyester-imide 180	QZY (EIW)	0.06 – 3.0	#9 – #42	60317-8	6109.5	MW30-C

Composite — Q(ZY/XY) (EI-AIW)

Thermal Class	Insulation Type	YIDA Product Code	Diameter Range (mm)	Diameter Range (AWG)	IEC Standard (60317)	GB/T (6109)	NEMA Standard
200°C	Polyester-imide Polyamideimide	Q(ZY/XY) (EI-AIW)	0.06 – 3.0	#9 – #42	60317-13	6109.2	MW35-C
220°C	Polyester-imide Polyamideimide	Q(ZY/XY) (EI-AIW)	0.06 – 3.0	#9 – #42	—	—	MW37-C

Applications

Polyesterimide enameled wire is the preferred choice for EV traction motors, aerospace actuators, high-reliability industrial motors, inverter-fed drives, and applications in harsh chemical or radiation environments. The composite EI-AIW variant with polyamide-imide topcoat is specified for the most demanding automotive and aerospace applications where Class 200-220°C thermal endurance is required alongside superior mechanical protection.

Frequently Asked Questions

What temperature range can polyesterimide wire withstand?+

Single-layer polyesterimide (EIW) is rated for continuous operation at 180°C (Class H). The composite polyesterimide/polyamide-imide (EI-AIW) variant extends this to 200°C (Class C) and 220°C (Class C+) depending on the specific formulation. All grades also perform well at sub-zero temperatures, making them suitable for extreme-range thermal cycling environments.

What is the difference between single-layer EIW and composite EI-AIW?+

Single-layer EIW uses polyesterimide as the sole insulation, rated at 180°C. Composite EI-AIW adds a polyamide-imide topcoat over the polyesterimide base, creating a dual-layer system rated at 200-220°C. The PAI topcoat provides significantly better mechanical abrasion resistance, chemical resistance, and thermal shock performance. EI-AIW is the standard choice for automotive traction motors and other high-reliability applications.

Why choose polyesterimide wire for EV traction motors?+

EV traction motors subject winding wire to sustained temperatures above 180°C, rapid thermal cycling from regenerative braking, high-voltage PWM inverter stress, and aggressive cooling fluids. Polyesterimide and composite EI-AIW insulations are specifically designed to withstand these conditions while maintaining dielectric integrity over the 15+ year vehicle lifetime. YIDA supplies EI-AIW wire to leading EV manufacturers worldwide.

What chemical resistance does polyesterimide insulation provide?+

Polyesterimide insulation provides excellent resistance to transformer oils, refrigerant gases (R134a, R1234yf), ATF transmission fluids, and common industrial solvents. The composite EI-AIW variant with polyamide-imide topcoat offers even stronger chemical resistance, making it suitable for direct oil cooling in traction motors and hermetic compressor applications.

YIDA Wire has manufactured enameled copper wire since 1984. IATF 16949, ISO 9001, and UL certified. Trusted by industry leaders across 50+ countries. Contact us for specifications →