Ultimate Guide to Battery Cable Size Chart

Battery cable sizing impacts an electrical system's performance and safety. Inadequate cable size can reduce effectiveness, cause voltage drops, and cause overheating. Proper battery cable sizing offers the best power transmission, extends battery life, and protects against electrical problems. The cable size must comply with safety regulations to ensure safety and smooth current flow. You can use a battery cable size chart to find the correct cable gauge for your application.

Jackery Solar Generators are solar-powered systems that reduce the dependency on grid energy and use clean, renewable energy to charge your devices. The solar cables compatible with Jackery Solar Generators ensure your device gets the optimal charge it needs.

Key Takeaways

• Battery cable parts are also referred to as battery leads and are mainly composed of copper and aluminum.
• A regular gauge reading is between 13 and 15 volts, and a reading of 12 while the battery runs indicates a problem.
• The cable thickness is measured using a standard American Wire Gauge (AWG) method, which ranges from 0000 to 40 and handles up to 302 to 0.0137 amperes, respectively.
• You can calculate the amperage of your device by dividing the appliance wattage by its voltage.

Types of Battery Cables   

A battery cable is a single conductor wire composed of heavy gauge copper. It is insulated with PVC and used to safely link the vehicle’s battery with the automotive parts. Battery cable parts are also referred to as battery leads. It features a positive lead connecting to the ignition and a negative lead connecting to the chassis. Here are some types of battery cables:

• SGX battery cable
• SGT battery cable
• Marine battery cable
• Fuse link or fusible link
• OFC (Oxygen Free Copper)
• CCA (Copper Clad Aluminum)

SGX Battery Cable

The SGX battery cable is flexible and suitable for high-temperature applications. It is soft-annealed, has chemically cross-linked polyolefin insulation, and has a temperature rating from -40°C to +125°C. The insulation trade-off is thicker and stiffer, with a high strand count. SGX can be a good choice if you need a high-temperature rating.

SGT Battery Cable

The SGT battery cable has a THHN-type wiring coating, particularly thermoplastic PVC insulation. THHN stands for thermoplastic high heat-resistant Nylon-coated. The insulated SGT battery cable is rated at 50 volts for 85 or 105o C. The strand count is low because the strands are more significant, which makes the wire stiffer to stay where you put it and can be bent around tight corners.

Marine Battery Cable

Marine wires are rated for high temperatures and wet or submerged applications. These wires are usually self-extinguishing and have a marine rating as the Coast Guard legal requirement. If a wire does not have a marine rating, building a cable out of it is not recommended. The voltage rating of marine battery cable is 600 volts, and its temperature rating is +105°C for dry and +75°C for wet.

Fuse Link or Fusible Link

A fuse or fusible link is a slow-acting fuse that looks like a wire. It has high-temperature insulation that won’t burn even if the fuses open. The fuse link is commonly used in alternator wires. It protects from catastrophic failure of the alternator diode, as the alternator wire would melt without the fuse link. Other use cases of fuse links are when the wire intake grid heater relays on engines.

OFC (Oxygen Free Copper)

A standard oxygen-free copper wire is 99.95% copper, and an OFC is as expensive as a standard cable of the same size. Stereo shops sell OFC wires to connect a high-power ampere, and a good-quality OFC wire is SAE-approved.

CCA (Copper Clad Aluminum)

A copper-clad aluminum wire is a copper-plated aluminum that is two sizes larger to have an optimal level of conductivity, as aluminum has 60% of the conductivity of copper.

Types of Battery Gauges or Size Cables   

A battery gauge or voltage gauge is a device used to measure battery voltage. Some gauges come with numbers, and others display an average position of the battery when the needle is placed in the middle of the gauge. If a number on the gauge shows a reading of 12 while the engine is running, it indicates a problem. The standard gauge reading should be above 13 and below 15 volts. Here is a list of some battery gauges:

• 10 Gauge wire
• 8 Gauge wire
• 6 Gauge wire
• 4 Gauge wire
• 2 Gauge wire
• 1 Gauge wire
• 1/0 Gauge
• 2/0 Gauge
• 3/0 Gauge
• 4/0 Gauge

10 Gauge wire: It is used for starter trigger wires, alternators (low power), and accessory leads.

8-gauge wire: This black wire, rated for 40 amps, is used for low-power alternators and accessory leads.

6 gauge wire: This wire is suitable for 55 amps and is also black. It is used in stock alternators, accessory leads, battery cables for ATVs and subcompacts, and golf cart wiring.

4 Gauge wire: A 4 gauge American wire is used for car battery cables, audio systems, and other residential and industrial applications. It is rated up to 160 amperes and is suitable for alternator wiring.

2 Gauge wire: A 2 gauge wire is commonly used in high-amperage capacity applications such as heavy machinery, industrial equipment, power converters, winches, etc. It has an ampere capacity of 115 amps at 60°C, 150 amps at 90°C, and 130 amps at 167°F.  

1 Gauge wire: A 1 gauge wire can be used for 6-cylinder or V8 automotive engines, power converters, and alternators in the range of 200 amperes.

1/0 Gauge: A 1/0 gauge wire is heavy-duty and is used in various electrical applications, such as 6-cylinder engines, stock V8s, welding equipment, marine batteries, solar panel and wind turbine installations, etc. For common insulation types, a 1/0 copper wire amperage capacity is 150A at a temperature of 75°C.

2/0 Gauge: A 2/0 gauge wire is more significant than a 2 AWG wire used in power distribution, transmission, bonding, and grounding. It has a diameter of 9.27mm and an ampere capacity of 135 ampere at 60°C. It is a low-resistance and high-ampacity wire and cable for high-compression engines, diesel engines, and large RV power converter house batteries.

3/0 Gauge: As set forward by the National Electrical Code (NEC), a 3/0 gauge wire is used for marine and diesel engines. It can be installed in dry and damp locations and operated in temperatures up to 90°C and in wet locations at 75°C. The wiring is used in raceways that are exposed to sunlight.

4/0 Gauge: With a rating of  230 amperes at 75^oC, the /0 gauge wire is used for high-power alternative battery banks. The rating can vary with copper or aluminum conducting material and insulation.

Importance of Battery Cable Sizing   

Proper cable size for electrical applications is essential for several reasons. Cable sizing standards and regulations must comply with safety guidelines. Proper battery cable sizing reduces the risk of electrical accidents due to overheating, minimizes voltage drops, and more. To optimize the performance of electrical systems, the bulk wire should be considered carefully, as with a proper cable size, the power flow will be smooth.

An appropriately sized cable prevents anticipated future breakdowns, ultimately enhancing the machine's productivity. Proper battery cable sizing prevents electrical failure, mitigates worker risk, and protects industries' assets. It also helps increase the lifespan of machinery and enables appliances to operate without strain under normal working conditions.

Wire Gauge Sizes Chart   

To choose a wire gauge size, you should look at the side of the wire for printing or a stamp in the connector that tells the size. Different stranding styles might indicate that no one size fits all. However, it is advisable to choose the larger wire size. A gauge of wire refers to its thickness and is represented by small numbers indicating thicker wire gauges and large numbers signifying thinner wires. The cable thickness is measured using a standard American Wire Gauge (AWG) method, which ranges from 0000 to 40 and handles up to 302 to 0.0137 amperes, respectively. Below is the wire gauge size chart, which helps measure the wire size in terms of thickness.

Battery Cable Size Chart    

A battery cable size chart is a way to visualize the effects of a component. A battery cable size chart helps you to determine the correct cable size required for your application and indicates what cable you need in your system. Below are the steps to help you know how to use the battery cable chart:

Step 1: Know your DC Amp Requirement: First, locate the current flow (in ampere) at the chart's top.

Step 2: Consider The Type Of Circuit You Have: Next, you need to select the correct circuit type from the two types: non-critical and critical. These types are mainly found in RV and marine applications. Some examples of essential kinds of circuits include solar panel feed, operational electronics, bilge blowers, and non-critical circuit examples, such as general lighting, appliances, pumps, etc.

Step 3: Determine Your Cable Length Needed: Generally, a cable is twice the length of an application. For example, if your application is 20 feet long, you will need a 40-foot wire, which is 20 feet for positive and 20 feet for negative.

Step 4: Find Your Correct Cable Size: Once you determine the DC ampere, you can intersect it with the total cable length range and identify the color code.

Step 5: Cable Conversion Table: Lastly, match the color code to the cable chart and find the correct circle specifications and size.

Battery Cable Amperage Capacity Chart    

Amperage is the unit of current that the appliances need in a certain amount to function when connected to a battery. For example, an inverter might use 150 amps of current, whereas a bulb might need only 10 amps to function. The maximum amperage is calculated by knowing the total current drawn by all the appliances. You can also see the amperage of your device by dividing the appliance wattage by its voltage. A voltage is produced when a positively charged terminal works with a negatively charged terminal. Voltage allows the electrons to move from the negative to the battery's positive end.

A battery cable amperage capacity chart determines the appropriate size for battery cables. It first calculates the device's amperage based on its wattage and then tells how to match the cable size according to the appliance's voltage. Cable sizing involves three critical parameters: amperage, cable diameter, and voltage.

The amperage capacity chart also showcases the relationship between cable size and amperage. To use the battery cable amperage capacity chart, select a battery cable size on the left and amperage from the column on the top. When you intersect the cable size and amperage, you can get the maximum length of wire that you can use. For example, a 6-gauge wire in a 12V battery cable size chart would carry 50 amperes in a maximum of 11.8ft.

Battery Cable Size	50 Amps	100 Amps	150 Amps	200 Amps	300 Amps
6 AWG	11.8ft	5.9ft	4.4ft	2.9ft	2.2ft
4 AWG	18.8ft	9.4ft	6.3ft	4.7ft	3.1ft
2 AWG	29.8ft	14.9ft	9.9ft	7.4ft	4.9ft
1 AWG	37.7ft	18.9ft	12.6ft	9.4ft	6.3ft
1/0 AWG	47.5ft	23.8ft	15.9ft	11.9ft	7.9ft
2/0 AWG	60ft	30ft	20ft	15ft	10ft
3/0 AWG	75.6ft	37.8ft	25.2ft	18.9ft	12.6ft

Is The Battery Cable Size Too Small? Or Too Big?  

The voltage drop is the first when the battery cable size is too small. This indicates that the wire voltage end is lower than the battery voltage. If there is a considerable voltage drop, the appliance will stop working. The voltage drop can be calculated using Ohm’s law, V=I*R, where V is the voltage, I is the current, and R is the resistance. If there is an increase in the current and resistance, the voltage drop increases. Resistance depends on the wire's length and thickness; hence, under-sizing your battery cable might create an excessive voltage drop.

Another area for improvement with a small battery cable size is overheating and wire melting. Heat is generated when current is passed through the wire, and more resistance in the wire causes overheating. If the battery cable is too small, the wire gets hot, starts melting, and can even cause fire.

If the battery cable size is big, cost is the primary consideration, as thicker wires are expensive. Unless you are running a battery cable of a few feet, there will be no additional cost. As the wire gauge increases, the weight of the battery cable increases. It is challenging to work with thicker cables, especially while bending and operating them in vehicles. However, with more portable and compact size options like the Jackery Solar Generator, you need not worry about cable sizing while using solar energy.

Jackery Solar Generators Explained

Jackery stands as a pioneer in the field of sustainability by selling around four million units of solar generators, portable power stations, and solar panels. The Jackery Solar Generator is a portable solar power system combining the Jackery Portable Power Station and Jackery SolarSaga Solar Panels. When the solar panels are placed outside on a bright sunny day, the cells in the solar panels trap sun energy and convert it into electrical energy. This electric energy is stored in a portable power station with a built-in inverter that converts direct current (DC) into alternating current (AC). The Jackery Solar Generators provide solar energy to charge your devices and keep them powered up during off-grid living, blackouts, or outdoor adventures.

Jackery Solar Generator 3000 Pro

Due to its massive capacity, the Jackery Solar Generator 3000 Pro is ideal for RV living, glamping, and camping. It comes with solid battery charging cables and a comfortable handle for direct charge. The solar generator can charge 99% of devices for indoor and outdoor purposes.

Appliance Working Hours

• Refrigerator (520W): 4.94H
• Heater (1800W): 1.42H
• Microwave (960W): 2.67H

Customer Review

“I have a Jackery Explorer 1500 and 3000 Pro. Both are great generators, and the 3000 Pro is a beast. They are both well-made and work great. I now have 6 panels that I can use simultaneously to charge the 3000 Pro quickly. They have good warranties. Buy with confidence.” - Dustin M.

Jackery Solar Generator 2000 Plus

The Jackery Solar Generator 2000 Plus supports multiple cable types to charge devices in various locations and situations. Its expandable capacity stores emergency backup power for power outages or unforeseen power cuts.

Appliance Working Hours

• Portable Air Conditioner (1150W): 1.5H
• Kettle (850W): 2.04H
• Hand drill (400W): 4.34H

Customer Review

“ Amazing. It was expensive, but I did appreciate the coupon. I went off the grid with it, and we love it. We live in a camper and power up everything for at least two days without charging but using everything, so I'm thrilled that we got it. We have a small jackery that we relied on, but now we have no problem with power.” - Marcin Powichrowski

Jackery Solar Generator 2000 Plus Kit (4kWh)

The Jackery Solar Generator 2000 Plus Kit (4kWh) can power heavy-duty devices, providing long-lasting reliability. The Jackery Solar Cables can connect battery backup with the solar panels for easy charging. The solar generator can power essential devices during off-grid living and extended blackouts.

Appliance Working Hours

• Coffee Maker (550W): 6.31H
• Outdoor Electric Grill (1700W): 2.04H
• Electric Oven (800W): 4.34H