Instead of shelling out a bazillion bucks for some power cords, I’m going to cut my own. The maximum load will be 13.8V @ 22A, and I believe this calls for 14 ga wire. Is there some reason why I couldn’t use 14 ga speaker wire instead of zip cord?
Vlad/Igor
A few questions:
Power cords for what? What is the environment in which they will be used? Is this AC or DC (although it sounds like the latter)? How long are the cords going to be? Is the 22Amp maximum load an occasional peak, or a near constant load?
Your insurance company?
I wouldn’t use zip cord - think about what you normally see zip cord used for: lamps and other devices that draw an amp or two at most.
I’d go with something heavier. 14 ga copper wire has something like 2.5 ohms per 1000 ft. A ten foot length passing 22 amps will have 12 watts spent in the wire alone. You can get a spool of 10 ga wire in metal flex conduit for much less than a bazillion bucks.
Compared to all the bad things that can happen to you with homemade extension cords, the store bought kind are a bargain.
22 amps? I’m not an electrician, but I believe that’s too small. I think the NEC says that regular house wiring requires 12 gage wire for 20 amp circuits and 14 gage wire for 15 amp circuits. Of course, those specifications take into account high ambient temperature (and are thus conservative), but at least they give you an idea of what is normally considered “safe.” At any rate, I think you need bigger wire. I’d say at least 10 gage. (I believe the NEC says 10 gage house wiring can be used on a 30 amp circuit. So you should be safe with 30 gage.)
As long as you use the correct gauge, you should be fine. The cord you use depends on the use. If whatever it is you are powering never moves or anything, a light weight cable like a lamp cord would probably be fine. If it is some power tool that may get moved around, have the cord driven over, stepped on, or generally abused, be sure to get some cable that will withstand the abuse. Get the right connectors and secure them well. If this is for AC, don’t ingore the grounding if your load is meant to be grounded. Also be sure that your metals agree. For instance, using aluminum conductor can eventually be a safety hazard if connected to a non-similar metal.
I like to make my own heavy duty extension cords because I can make them cheaper and better quality.
I rechecked the wire load, and I do indeed need 12 ga multistranded. 14 ga solid wire is rated to 32A, but multistranded is rated at only 17A. I’m running DC power from a car battery to a 100W radio inside a car, and the run will be about 10ft at most. The radio came with a 12 ga multistranded power cord, fused on both sides, and I am going to build several copies of it. A 10’ run of 12 ga losing 12W will only lose about 1A at 13.8V, so I don’t think that’s an issue here.
Vlad/Igor
Now that you’ve answered the questions posed in post #2, my only observation would be regarding the type of insulation/protective jacket on the cord assemblies you plan to make. Look for a string of letters either printed or embossed on the outer jacket of the original along with 12 for the gauge and 2 for the number of conductors. It may be something like SJO or SVT-you want to match this type of cable when making your extra cords so they will be capable of performing properly in the intended application.
Sounds like a Ham radio installation. Use the same guage as suplied by the manufacturer (Icom, Yaesu, Kenwood), and you’ll have no problems. I hook directly to the battery with a fuse in each leg at the battery. Some supplied power cords have the fuses located near the radio itself. My new FT-857D power cable has the fuses located at the battery connection. First one I’ve seen like that. And it uses automotive fuses too, better than the glass fuses.
73 de WØGOM
I entered the data into a spreadsheet. If the amp is 10 feet away, using 12 AWG wire will reduce the power to the amp by 9.6% at peak current. Using 10 AWG wire will reduce the power to the amp by 6.2% at peak current.
That is precisely what I’m doing. I just got an 857D, and want to be able to run it in two cars as well as from a marine battery at home. I’m also going to standardize the power couplings for my 817 and an Alinco 2M/440 mobile radio I have so that I can switch power from radio to radio or car to car very easily. I’m making up a shopping list from Mouser, and they have 12 ga speaker wire, plus in-line automotive fuse holders, etc. I’m also going to make a CAT cable to clone the 857 from the 817.
Thx and 73 de KF4VCC
Pay attention to danceswithcats’ post about the insulator. If you get plain jane speaker wire, the insulation may not hold up when used in a vehicle, especially if it might be exposed to high temperatures, water or road salt. I don’t know what the likelihood of failure is, but I’d play it safe.
Anderson Powerpoles I hope! That’s what I have on all mine. I’m using my 857D in the shack so cut off most of the power cable but for 3 feet. Put on the 30A power poles so it plugs into my Rigrunner clone power panel. I use the 12 Ga. red/black cable normally sold at hamfests. Usually buy 25-30 feet at a time. Looking in my Mouser catalog, I don’t see anything suitable. Latest catalog I have is #607. Also don’t see any good weather resistant fuse holders.
I run a IC-2720 in one car, and a FT-90 in another. All with powerpole connectors. BTW, the crimper sold by West Mountain Radio works very well.
I’ve heard about Anderson power poles for a few years now. I was looking at a Molex 2X3 plug/recepticle with three connections for each wire through the recepticle. What advantage would Anderson connectors have over the Molex? I’ve been to Anderson’s website, but am still trying to figure out what I would use.
Vlad/Igor/KF4VCC