What is MG High Temp Wire?

The Mica Glass Solution for 450°C | 550°C 

When industrial heat far exceeds the limits of Teflon (PTFE) or even high-grade TGGT Wire, you need an electrical conductor designed with mineral-based insulation. The specialized solution for extreme, continuous high-temperature service is MG Wire (Mica Glass Wire).

MG Wire is engineered for sustained performance in environments where temperatures can climb to 450°C or 550°C.   Standard MG wire is rated up to 450°C while the Duraflex MG Wire is rated up to 550°C.   These are the essential choices for wiring the interior of industrial ovens, kilns, and other heating equipment.

Below is information installers, engineers, maintenance supervisors, and OEM manufacturers should know about selecting this maximum-heat wire.

1. The Extreme Heat Equation: Mineral-Based Defense

MG wire relies on materials that are inherently non-combustible and thermally stable, avoiding the degradation of polymer-based insulation.

• Continuous Temperature Rating: The primary advantage is its rating for sustained operation from 450°C up to 550°C—the highest temperature rating available for flexible appliance wiring.

• Insulation Integrity: Unlike organic materials, the mica and fiberglass composite will not melt, burn, or become brittle when exposed to extreme dry heat, ensuring the wire's dielectric strength remains intact over its lifespan.

• Dry Heat Use: MG wire is designed for dry conditions. In high-moisture or oil environments, TGGT Wire (which has a Teflon seal) is typically preferred, as the fiberglass braid on MG wire is absorbent.

2. Construction: Maximizing Thermal Stability

MG wire is built with layers of non-combustible material to protect the conductor from the surrounding intense heat.

• Conductor: The conductor is finely stranded, nickel-plated copper. Nickel plating is mandatory for this temperature range, as it prevents the copper core from oxidizing or suffering from "red rust," which would increase resistance and lead to circuit failure.

• Mica Tape: The insulation surrounding the conductor is a layer of flexible Mica Tape. This mineral provides the primary, high-performance electrical insulation and thermal stability.

• Fiberglass Braid: A layer of high-strength is the fiberglass braid jacket which provides the mechanical and abrasion resistance.

• Finish: The outer braid is typically finished with a high-temperature saturant, which binds the fibers and adds protection against installation damage.

3. Sizing, Rating, and Compliance

MG wire requires careful selection based on voltage, current, and compliance for extreme-temperature appliance applications.

• Voltage Rating: MG wire is typically rated for 600 Volts, making it suitable for standard industrial heating circuits.

• Sizing (AWG): It is generally available in gauges 18 AWG to 4/0 for internal equipment wiring, heating elements, and control circuits within the thermal enclosure.

• UL Listings:  MG wire is typically UL listed and meets requirements like UL Style 5107, UL 5332, or UL 5400 (Duraflex version), ensuring code compliance and fire resistance for industrial applications.

• Installation Note: Always use high-temperature terminal blocks and lugs that are also rated for the 450°C environment to prevent connection points from failing before the wire does.

4. Primary Applications: Where MG Wire Is Essential

MG wire is required in industrial settings where the internal operating temperature exceeds 250°C:

• Manufacturing: Internal wiring for industrial ovens, commercial drying equipment, furnaces, and kilns.

• Control Panels: Wiring near boilers, steam generators, and process heaters where ambient temperatures are high.

• Appliances: Internal connections for high-wattage commercial cooking equipment (e.g., pizza ovens, deep fryers, baking equipment).

• Foundries: Power and control wiring exposed to radiant heat sources.

5. Why Buy MG High-Temp Wire?

When purchasing MG High-Temp Wire, the slight premium you pay is a direct investment in safety and reliability. A cheaper, non-rated cable will degrade quickly, leading to brittle insulation, short circuits, and potentially catastrophic equipment failure.

Choosing MG wire guarantees:

1. Safety: Compliance with fire resistance standards.

2. Longevity: Ensures internal wiring lasts as long as the equipment itself.

3. Efficiency: Eliminates costly downtime associated with melted or failed conductors.

Wire America is proud to offer this product by the foot or by the spool with fast shipping to your location. 

Click Here to Shop Our MG 450°C | 550°C High Temp Wire Selection

If you are looking for information on other high-temp wires we offer check out these options below:

At Wire America, we believe in genuine conversation. You'll always talk with real people who understand that every project requires careful product selection. We're here to ensure you feel educated, confident, and great about your final purchase. Feel free to give us a call to discuss your project! You can reach us at: 833-268-8644

⚠️ Important Disclaimer: Safety and Compliance

Wire America provides this information as a guide only. Electrical installations must strictly adhere to the National Electrical Code (NEC) and all state, local, and jurisdictional requirements, which vary widely. Always consult a licensed electrician, electrical engineer, or the local inspecting authority before purchasing material or starting any electrical project. Wire America assumes no liability for the installation, use, or interpretation of these guides.

For information on other high-temp wire we offer check out these options below:

SRML (Silicone Rubber Motor Lead Wire) - 150ºC | 200ºC

TGGT (Teflon / Glass / Glass / Teflon, PTFE Insulation) - 250°C