Power cord question

Shantarr.Dalrae

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Mar 23, 2010
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I have two power cables, each rated differently.

The one that came with my monitor is rated @ 10a

The one that came with my power supply is rated @ 17a

Is there a set standard in today's power supply market that defines what is the reccomended amperage for power cables?

Does it matter?

What is the Max?

Thank you!
 

BillParrish

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Aug 25, 2006
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7,520
You have it backwards, the difference in those cables will be the size (gage) of the conductors/wires in the cables.

Depending on the amount of current pulled from the wall AC outlet the wire size in the power cord will vary, with 12 gage being about the heaviest I have ever seen and very rare as it is very thick and expensive.

Then 14 gage fairly common on heavy duty high draw equipment.

16 gage is very common for PC power supplies

18 gage for crappy PC power supplies and lower powered devices. ( This is the standard 'Lamp cord" size - a lot of table lamps use this size in a 2 conductor side by side style with no outer jacket) this makes excellent inexpensive speaker wire too. )

20 or 22 guage for very low powered stuff but in general not used much for AC power cords.

You can find NEC (national electric code) standards for how many amps are allowed in a power cord etc. but with stuff built all over the world you might find several different "ratings" for say a 3 conductor 14 gage stranded copper wire insulated with outer sheath covering.

So its all about the size of the wire inside, the bigger the better as it can carry more power/current before it gets hot melts and burns the house down.

Your power supply pulls more current (or it has the capability to) from the wall than your TV. Look on the labels of both and it will tell you max AC used.

In USA most (read almost all) wall outlets in rooms other than the kitchen are protected by a 15A circuit breaker which means you are not going to get more than about 15A of 115V AC out of the wall . If you try you will trip the breaker.
 

KaizerDan

Gawd
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Jun 27, 2007
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667
Its always a safe bet to go above the cheapest, as far as 16 gauge for a home pc? yea you can get away with it if you have the right computer, but if your computer has too much of a draw the cord will feel hot. Those ratings(and breakers) are basically just there to protect the wire from getting too hot and melting the insulation over time. The 17A is just what it can draw at its max, itll rarely ever come to that, and brief seconds of that wont harm the wire. if it does draw that for a long enough time, itll trip your 15A breaker/fuse because its protecting the wire from getting hot( its assuming said persons followed the NEC code and put in the proper rated wire) A kitchen/bathroom/laundry/dinning room should be a 20A breaker and 30A rater wire(12 gauge)


/end incoherent sum up?
 
Last edited:

tdg

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Jan 27, 2003
Messages
3,816
The most commonly used power cord is the 18 gauge, which as a cord is good for about 10 amps. I have some server grade Y power cables (2 ended) in my rack which are 16 gauge (13 amps). The power distribution bars in my racks have some of the heaviest cable to be used, which are 12 gauge (12 amps @ 240 volts, 23 amps if I used 120 volts).

If you look on the wire you should see the gauge then 3 if it is a grounded cord, such as 18/3. Ampacity varies by who you ask and how the actual wire gauge is used. 18 gauge being able to carry 10 amps is usually sufficient, on a 120 volt circuit that is 1,200 watts.
 
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