Class H Silicone Rubber Motor Lead Wire – JG and JE Series
Class H silicone rubber motor lead wire is a specialised single-conductor wire designed for the connection between motor winding terminals and motor terminal boxes in Class H insulation motors, generators, and transformers. IEC 60085 defines Class H insulation as having a maximum continuous operating temperature of 180°C — the second highest standard insulation class — and the motor lead wire connecting to Class H windings must be rated to survive the full thermal environment at the winding terminal without degradation over the motor’s service life.
The JG and JE designations are Chinese standard codes: JG refers to a solid or stranded silicone rubber insulated motor lead wire; JE is the flexible stranded variant. Both use extruded silicone rubber (VMQ) insulation providing 200°C continuous rating — giving a 20°C thermal margin above the Class H winding temperature — combined with the flexibility required for the motor lead to be routed from the winding terminal through the motor frame to the terminal box without cracking or fatiguing at the tight bend radii encountered inside motor housings.
Technical Specifications
| Parameter | Specification |
|---|---|
| Conductor material | Tinned or bare copper, solid (JG) or stranded (JE) |
| Insulation material | Extruded silicone rubber (VMQ) |
| Min avg insulation thickness | 30 mils (0.76 mm) |
| Min insulation at any point | 27 mils (0.69 mm) |
| Insulation class | Class H (180°C) — wire rated 200°C for thermal margin |
| Voltage rating | 600V AC |
| AWG range | 18 AWG – 6 AWG (10 AWG – 6 AWG in larger motor applications) |
| Optional covering | Treated fiberglass braid (for added mechanical protection) |
| Flame rating | Horizontal flame, UL VW-1 |
| UL file number | E333030 (Style 3135) |
| Standard | GB/T 5013, UL AWM 3135, IEC 60085 Class H, RoHS |
| Colour options | Red, black, white, yellow, blue, green (phase identification), custom |
| Packaging | 25 m / 50 m / 100 m coils, cut to length from 1 m |
Insulation Class Reference
| IEC 60085 Class | Max temperature | Typical wire insulation |
|---|---|---|
| Class B | 130°C | PVC 105°C grade (derated) |
| Class F | 155°C | Silicone rubber (AGR/AGRP) |
| Class H (this product) | 180°C | Silicone rubber 200°C (JG/JE) |
| Class C | >180°C | Mica tape or PTFE wire |
Key Features
Thermal & electrical
- 200°C continuous — 20°C margin above Class H requirement
- 600V AC rated — covers standard LV motor supply voltages
- UL AWM Style 3135 recognised — File No. E333030
- Self-extinguishing horizontal flame / UL VW-1 rated
- No insulation shrink-back at soldering iron contact
Mechanical & installation
- JG (stranded) — flexible for tight motor housing routing
- Optional fiberglass braid — added mechanical protection
- Phase colour coding — red/yellow/blue for 3-phase identification
- Cut-to-length from 1 m — ideal for motor repair and OEM assembly
- RoHS compliant — halogen-free silicone insulation
Common Applications
Class H motor lead connections
The primary application is the motor lead — the short length of wire connecting the motor winding terminal to the terminal box screw connections. In a Class H insulation motor, this wire sits at the highest temperature point in the motor and must maintain its insulation properties throughout the motor’s service life. The JG/JE silicone rubber wire provides the required 200°C rating with the flexibility to be routed through the small clearances inside the motor end shield and terminal box.
Generator and alternator internal wiring
Used for stator and exciter winding connections in generators and alternators where operating temperature, vibration, and the requirement for reliable long-term performance in remote or unattended installations demand a wire that will not harden, crack, or lose insulation integrity over decades of service.
Transformer internal lead connections
Used as the connection lead between transformer winding ends and the terminal board in dry-type transformers operating at Class H temperature, where the lead must survive the winding hot spot temperature while remaining flexible enough to accommodate thermal expansion movement.
Other applications
- Submersible pump motor lead wire
- Servo motor and stepper motor lead connections
- Industrial fan and blower motor internal wiring
- HVAC compressor motor lead replacement
Ordering Information
Specify series (JG solid or JE stranded), AWG size, optional fiberglass braid covering, insulation colour, and required length. Phase-colour-coded sets (red/yellow/blue or red/black/green) available for 3-phase motor lead replacement. Cut-to-length from 1 m for maintenance and repair orders.
Motor repair sets available. Pre-cut to specified length with stripped ends. Contact us for pricing within 24 hours.
Why Choose CableApex
CableApex manufactures JG/JE Class H motor lead wire under UL Follow-Up Service (File No. E333030, Style 3135). All production undergoes 100% spark testing and conductor resistance verification. We supply to motor manufacturers, motor rewinding workshops, pump OEMs, generator manufacturers, and maintenance distributors across more than 40 countries.
