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# 12v 14awg distance?

#### thatonenerd

##### New Member
Hi, Im just wondering whats the entire distance that you can extend a 12v 10a power supply with 14awg wire? Thanks =)

#### Papabravo

##### Well-Known Member
Your question is incomplete. There is probably no appreciable distance where you can get the full 12 volts AND the full 10 amperes. From standard tables you can find the resistance of the wire, compute the IR drop of the hot lead and the ground lead and come up with a voltage and a current that will be available for a given load. Remember the load will only take as much current as it needs and it will not take the maximum capacity of the supply in all cases.

The correct framing of the question might be something like: "At what distance will I be able to have 8 Volts delivered to a 1 Ω load". This means the wire out and back will drop a total of 4 Volts, and the current through the load will be 8 amperes.

Also there will be a 2 Volt difference between the ground at the source and the "ground" at the load.

One table I consulted has a value of 2.53Ω per 1000 feet for AWG 14 wire. I did not look closely to determine if that was solid or stranded.

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#### Tony Stewart

##### Well-Known Member
Most Helpful Member
Make sure you factor twice the distance since voltage drop occurs on both +12 and 0V return.

#### Tony Stewart

##### Well-Known Member
Most Helpful Member
A ChatAI can answer this better now than Google and Bing which are starting to use AI and the ChatGPT API. As well, Wikiwand uses AI on Wiki pages if you select > Give me the top 10 facts or answer it so a 10 yr old will understand it. This will revolutionize medical, legal and engineering advice in this decade and it has already started.

e.g. I put in your question.
The distance that you can extend a 12V 10A power supply with 14AWG wire depends on several factors, such as the voltage drop, wire resistance, and load current. The longer the wire distance, the higher the resistance and voltage drop, which can affect the performance of the power supply and the connected devices.
To calculate the maximum distance that you can extend the power supply with 14AWG wire, you can use the following formula:
Distance = (Resistance x Current x 2) / Voltage Drop
where:
• Resistance is the resistance of the wire in ohms per unit length
• Current is the maximum current that the power supply can deliver in amperes
• Voltage Drop is the maximum allowable voltage drop in volts
Assuming a maximum voltage drop of 5% and a wire resistance of 2.5 ohms per 1000 feet (based on the American Wire Gauge standard), the maximum distance that you can extend a 12V 10A power supply with 14AWG wire is approximately 100 feet.
However, it's important to note that this is only a rough estimate, and the actual distance may vary depending on factors such as the specific wire used, the temperature, and the ambient conditions. It's also important to ensure that the wire is properly rated for the current and voltage requirements of the power supply, and to use appropriate wiring techniques to minimize voltage drop and maximize performance.

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My simple answer is if you can tolerate only 1% voltage drop and you know the wire pair for AWG14 is 5 ohms per thousand feet, then all you need to know is your equivalent load resistance must be more than 100x times the wire resistance.

Tony

#### shortbus=

##### Well-Known Member
Most Helpful Member
There are many 12V wire amperage charts online, no math involved. If this is for an automotive job the frame or body makes the ground or return, or just use the same chart for the return.

#### thatonenerd

##### New Member
Id like to add 8FT of 14awg cabling to the adapter. I have dimensions of the adapter attached. Is 14awg safe enough for this?

The chart websites seem to say it should be okay?

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#### Nigel Goodwin

##### Super Moderator
Most Helpful Member
It's no issue at all - but if you wanted to be even more safe, extend the mains side instead, where the current is only about 1/10th.

#### thatonenerd

##### New Member
It's no issue at all - but if you wanted to be even more safe, extend the mains side instead, where the current is only about 1/10th.
Thank you, that helps. It's much appreciated =)

#### Tony Stewart

##### Well-Known Member
Most Helpful Member
Not only is it better to extend the AC side for performance, but there is also a way to do this without needing an extension cable.

The DC side is often built with thin internal remote voltage sense wires, which allows them to use more flexible and cheaper DC cables on the adapter that may have more loss at the expense of less efficiency and some heat in the cables at max current. Yet this remote sensing would be lost if you simply extended the DC cable. I know this was done in universal adapters that I have modified for remote voltage control and they supply optional barrel plug sizes which had 3 pins for all the different plugs. The 3rd pin was for remote sensing.

Now back to the extension cable.

If I convert 8ft to cm *2.54 / " I get 244 cm then add the original 120 cm cordset to get 3.6m I found this IEC to US type \$10 cordset in 3.6 m length. (12ft)

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