36 SWG Enameled Copper Wire: Specifications and Applications for High-Density Winding
In modern electronics and electrical engineering, copper winding wire is the “blood vessels” of key components such as inductors, transformers, motors, and relays. 36 SWG copper winding wire, due to its extremely fine diameter and excellent performance, plays an irreplaceable role in miniature and high-density electronic devices.
I. Core Parameters
1. Wire Diameter and Cross-Sectional Area
Copper core diameter: 0.193 mm (SWG standard). After enameling, the maximum outer diameter increases to 0.208 mm to ensure uniform insulation coverage.
Cross-sectional area: Only 0.029 mm², equivalent to 1/4 the thickness of a human hair, suitable for high-density winding needs.
2. Electrical Performance
DC resistance: As high as 606Ω/km, far exceeding that of thicker wire gauges (e.g., 14 AWG resistance is approximately 8.3Ω/km), making it suitable only for milliampere current scenarios. Current Carrying Capacity: Limited by the thin wire diameter, the continuous current carrying capacity does not exceed 100mA. Overcurrent can easily cause overheating and melting.
3. Materials and Insulation
Material: 99.99% high-purity oxygen-free copper with a conductivity of >58 mS/m, ensuring low signal loss.
Insulation: Polyurethane or polyesterimide enamel, with a temperature resistance rating ranging from Class B (130°C) to Class F (155°C), adaptable to various heat dissipation environments.
SWG standard and bare wire diameter
| Specification | 36 SWG |
| Bare wire diameter (mm) | About 0.193mm |
| Cross-sectional area (mm²) | About0.0293 mm |
2. The Nature of Copper Winding Wire
Copper winding wire is made by coating a high-purity copper conductor with one or more layers of extremely thin insulating varnish. This insulating layer electrically isolates the conductors within a confined space, enabling tight winding while maintaining excellent conductivity.
II. Insulation Film Thickness of 36 SWG Copper Winding Wire
| Insulation grade | Description and Application | Thickness of insulating paint on one side (approximate value) | Enameled wire outer diameter (approximate) |
| Grade 1 (G1) / Thin film | It is suitable for occasions with extremely limited volume, small number of winding coils and relatively low voltage requirements. | About 0.005 – 0.010mm | 0.203 -0.213mm |
| Grade 2 (G2) / Grade 2 / Standard paint film | The most commonly used grade, balancing winding density and electrical insulation performance. | About0.010 – 0.018 mm | 0.213 – 0.229mm |
| Grade 3 (G3) / Grade 3 / Thick Film | Suitable for applications requiring higher voltage resistance, stronger wear resistance or double insulation protection. | About0.018 – 0.025mm | 0.229 – 0.243mm |
Insulation film thickness is a key parameter that determines winding wire volume, dielectric strength, and winding density. For 36 SWG winding wire, there’s no fixed thickness; it depends on the standard and selected insulation grade.
2. The Significance of Insulation Thickness
Volume Control: A higher insulation grade (thicker) results in a larger outer diameter of the enameled wire, which in turn increases the final volume of the winding coil, potentially impacting the design of high-density windings.
Electrical Strength: A higher insulation grade (thicker) results in a higher breakdown voltage between conductors, enhancing product reliability.
Mechanical Protection: A thicker insulation film provides improved wear resistance, reducing the risk of damage to the varnish during high-speed winding.
III. Applications
1. Micro Motors and Precision Drive Systems
Micro DC Motors: These are used in drive motor coils in toys, electric toothbrushes, medical pumps, and CD/DVD drives.
Drone Motors: These are used in brushless or brushed motor windings for small or micro drones, achieving high efficiency and lightweighting. Model aircraft motors: High-performance, high-density windings used in model devices such as remote-controlled aircraft and cars.
Microvibration motors: Vibration motor coils that provide tactile feedback in mobile phones and wearable devices (such as smartwatches).
Medical devices: Micro drive systems in minimally invasive surgical tools and precision syringe pumps.
2. High-frequency transformers and power modules
High-frequency transformers: Primary and secondary windings used in small power adapters, chargers, and LED driver power supplies.
Switching power supply inductors: Precision inductors used in various filtering, energy storage, and choke circuits.
3. Precision electronic components and sensors
Precision inductors: High-Q coils used in radio frequency (RF) circuits, filters, and oscillators.
Electromagnetic relays: Small relay coils used in control circuits require extremely fine wire to increase the number of turns and ensure sufficient magnetic force.
Various sensor coils:
Electromagnetic sensors: Such as magnetic field sensors and auxiliary coils for Hall-effect sensors.
Displacement/proximity sensors: Precision detection coils used in industrial automation. Read/write head coils: used in various storage media or card reader devices.
Though as thin as a hair, 36SWG copper winding wire carries the precision dreams of the modern electronics industry. From the precise control of micro relays to the copper interconnect revolution in AI clusters, its value continues to be amplified in “small scenarios.”