The right ampacity of 18 AWG copper wire ensures its safe, efficient, and long-term use. 18 gauge wire ampacity refers to the maximum current that a wire can carry without overheating. For 18 AWG copper wire, the ampacity depends on the temperature. At 60°C (140°F), it's 14 amps; at 75°C (167°F), it's 18 amps; and at 90°C (194°F), it's 22 amps. Knowing 18 AWG ampacity, you’ll ensure proper electrical design and installation for a range of applications.

What is 18 AWG wire used for?

Let’s discuss the most common applications of 18 gauge wire amps: 

• Electronics and Small Appliances. 18 AWG wire is used for lamps, fans, and kitchen appliances. With its size, 18 AWG handles moderate currents efficiently.  It is also perfect for wiring in the tight spaces because it is flexible. 
• Lighting. The 18 AWG wire is usually used in lighting systems, both residential and commercial. 18 AWG connects light fixtures to power sources and provides the safe and efficient transmission of electricity.
• Automotive Wiring Harnesses and Radio. In the automotive industry, 18 AWG wire is used in wiring harnesses to connect various electrical components. It's also applicable for automotive radios, speakers, and other entertainment systems. 
• Low-Voltage Control Circuits (Automation Systems, HVAC Controls). 18 AWG wire is well-suited for low-voltage control circuits in automation systems and HVAC controls. It helps regulate and manage functions like temperature control. 
• Speaker Wiring. This wire gauge is often employed for connecting speakers to audio systems due to its ability to handle the electrical demands of audio signals. This leads to clear and high-quality sound transmission.
• Security Systems.18 AWG wire is used in security systems for connecting sensors, alarms, and cameras. Its appropriate size and conductivity make it reliable for transmitting signals in security setups.
• Electronics. Beyond small appliances, 18 AWG wire is used in various electronics applications such as power distribution within devices and connections between components on circuit boards.
• Doorbells and Thermostats. Doorbell systems and thermostats commonly use 18 AWG wire for wiring. Its size and flexibility enable easy installation in residential settings.

Why are 18 AWG Aluminum Cables Not Common?

18 AWG aluminum cables are not the best option for small gauges like 18 AWG. This is because aluminum is softer and more malleable than copper. This makes it more prone to damage, especially in smaller gauges like 18 AWG. Small gauges require flexibility, and copper cables are more flexible. Copper's superior conductivity, lower resistance, and greater durability make it a more reliable choice for lots of applications.

Types of 18 AWG Copper Wires

• THHN/THWN. These wires are versatile building wires suitable for general applications. THHN (Thermoplastic High Heat-resistant Nylon-coated) and THWN (Thermoplastic Heat and Water-resistant Nylon-coated) wires are used for both dry and wet locations. They are used in residential and commercial wiring for outlets, switches, and lighting. In size 18, THHN wire is used for control circuits and lighting.
• VNTC. VNTC wires are often used in industrial environments for control circuits, power distribution, and instrumentation. Their versatility and resistance to oils and chemicals make them suitable for various machinery and factory settings. 18 AWG VNTC is also suitable for trays.
• MTW. MTW wires are designed for machine wiring and internal electrical connections. Their flexibility and flame resistance make them a go-to choice for various manufacturing processes.
• SIS. Heat and moisture resistant SIS wires are suitable for use in switchboards and panelboards. 
• TFFN. TFFN wires are available in 18 AWG and are used for lighting fixtures and other applications requiring flexibility. It’s easy to install them in tight spaces, which is great for compact devices.
• SPT-1/SPT-2. These parallel cords are used for small appliances, lamps, and light-duty applications. SPT-2 cords are thicker and can carry more current and are preferred for heavier loads. 
• Speaker Wire. This wire provides clear and high-quality sound because it was designed specifically for connecting speakers to audio systems. Its construction ensures minimal signal loss, allowing for optimal audio performance in home theaters, sound systems, and entertainment setups.