Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

Amps and Wire Gauge in 12V Electrical Circuits

Maximum current - amps - through a 12V circuit - related to size (AWG) and length of wire

Sponsored Links

Conductors in electrical systems should not be sized with voltage drops exceeding 3%.

For a 12V system the maximum voltage drop should be less than (12 V) x 3% = 0.36 V.

Conductor sizes (AWG) related to maximum current through a 12V electrical wire and length of cable - are indicated below:

American Wire Gauge (#AWG)
Length
(feet)
Maximum Current (amps)
5101520253040506070
15 16 12 10 10 8 8 6 6 4 4
20 14 12 10 8 8 6 6 4 4 4
25 14 10 8 8 6 6 4 4 2 2
30 12 10 8 6 6 4 4 2 2 2
40 12 8 6 6 4 4 2 2 1 1/0
50 10 8 6 4 4 2 2 1 1/0 1/0
60 10 6 6 4 2 2 1 1/0 2/0 2/0
70 10 6 4 2 2 2 1/0 2/0 2/0 3/0
80 8 6 4 2 2 1 1/0 2/0 3/0 3/0
90 8 4 4 2 1 1/0 2/0 3/0 3/0 4/0

Note! Failure to use an adequate size may result in a fire. Always secure electric wires with fuses.

  • 1 ft (foot) = 0.3048 m

Wire Gauge Design Procedure

  1. calculate total length of wire from source to device and back again
  2. determine amount of current in wire
  3. determine correct wire gauge in the intersection of amps and feet

Note! Wire size based on 3% (0.36 V) voltage drop in a 12 Volt circuit. Always oversize wires if voltage drop is critical.

12 v cable length maximum amps

print 12V Cable Length Diagram

Example - 12 V Cable and Maximum Length and Current

The maximum current in a 12 V gauge #6 (13.3 mm2) cable with length 15 m is approximately 15 amps according the diagram above.

The maximum current in a gauge #10 (5.26 mm2) cable with length 15 m is approximately 5 amps.

Sponsored Links

Related Topics

Related Documents

Tag Search

  • en: amps wire gauge current length AWG
  • es: amperios calibre del cable longitud actual AWG
  • de: Verstärker Drahtstärke aktuelle Länge AWG
Sponsored Links

Search the Engineering ToolBox

- search is the most efficient way to navigate the Engineering ToolBox!

Engineering ToolBox - SketchUp Extension - Online 3D modeling!

3D Engineering ToolBox Extension to SketchUp - add parametric components to your SketchUp model

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro .Add the Engineering ToolBox extension to your SketchUp from the SketchUp Pro Sketchup Extension Warehouse!

Translate this page to
About the Engineering ToolBox!

Privacy

We don't collect information from our users. Only emails and answers are saved in our archive. Cookies are only used in the browser to improve user experience.

Some of our calculators and applications let you save application data to your local computer. These applications will - due to browser restrictions - send data between your browser and our server. We don't save this data.

Google use cookies for serving our ads and handling visitor statistics. Please read Google Privacy & Terms for more information about how you can control adserving and the information collected.

AddThis use cookies for handling links to social media. Please read AddThis Privacy for more information.

Citation

This page can be cited as

  • Engineering ToolBox, (2004). Amps and Wire Gauge in 12V Electrical Circuits. [online] Available at: https://www.engineeringtoolbox.com/amps-wire-gauge-d_730.html [Accessed Day Mo. Year].

Modify access date.

. .

close

3D Engineering ToolBox - draw and model technical applications! 2D Engineering ToolBox - create and share online diagram drawing templates! Engineering ToolBox Apps - mobile online and offline engineering applications!

Scientific Online Calculator

Scientific Calculator

9 25

Sponsored Links
.