Hi fellas, How many amps will an 8ga wire handle with (yellow) 10ga crimp connectors? I'm installing a 100A alternator with an 8ga output wire. I have some yellow crimp connectors that the 8ga wire will fit in, and they have the correct size ring hole for the alternator output post.
You really need to get the right size terminals. Wrong size terminals do not crimp properly! Also you need to know the lenth of the wire to determine the amps it will carry. Bones
10 AWG cable is rated for 30 amps. So the Yellow lugs are 30 amps. By cutting copper off of the 8 AWG cable to fit into Yellow lugs you just made a 10 AWG cable.
If your not removing any of the #8 wire and using a #10 lug it will work depending on your load. Not a good practice at all but you need to know the amp load with everything turned on. There is a safety factor built in to every electrical part, but it’s definitely not a good practice to use it. Auto Zone and other stores sell lugs. You need to check the load, Engine running, lights on, AC on high, radio on, and the one missed brake lights on too. It with all that, your clamp on DC amp load is at 30 its livable and if your using THHN insulation it’s 40 amps. If you have an electric fan all bets are off if you have AC. I run on a #10 (correct lug) with a max of 29 amps and with AC on low fan it’s 19. I have never used everything. Today most of us install a 100 amp alternator but none of us install 100 amp amp wiring. Most use #8 as a feed with few using a #6.
99% percent of the time your alternator will only be putting out 20 or 30 amps and your 10 gauge wire will be fine.. it’s that one time your battery gets low and your alt goes to full output and that 10 gauge wire turns into a fusible link.
Ok, thank you for the advice. The output stud on my alternator is about a #12 stud (approx .210"). Closest I can find to that is a 8ga. ring connector with a 1/4" hole. Autozone up the road has them.
I don’t know what Menards or Lowe’s has for copper wire ends but that’s what I would use. Try an electrical supply store.
Also I would solder the connectors to the wire to avoid the risk of the too large wires pulling out. I’ve seen it before. They needed a new car afterwards.
Like others have said, get the right ends. McMaster-Carr or Digi-Key both have 100's if not 1000's of options, in stock, and ready to ship. This is a pet peeve of mine, but give the damn crimp connectors to your favorite enemy and order a good soldiering iron and learn how to use it. Then solder on the ends and cover with heat shrink. Do it once, Do it right, and it will last forever, or at least close to it. https://www.mcmaster.com/electrical-connectors/terminal-type~ring/for-wire-gauge~8/ https://www.mcmaster.com/soldering-irons/adjustable-temperature-soldering-stations-9/
I have a hydraulic crimper for larger cables. For a 100A alternator, I use 4ga fine strand-copper cable and tin-plated copper crimp connectors. https://www.mcmaster.com/terminals/heavy-duty-battery-terminal-lugs/for-wire-gauge~4/ At a previous place of employment, a major automaker, I demonstrated the difference between a crimp connector and a soldered connector, to prove to an investment group the lower value of soldering, and not just in the time and expense of the operation. A hydraulically crimped 0ga fine-strand copper cable can support 1,067lbs. A soldered 0ga fine-strand copper cable will pull out of its connector at 221lbs. https://www.instron.com/en-us/resources/test-types/tensile-test A properly crimped connector will have zero-voids, and with glue-lined heat shrink over the seam, it will have no moisture intrusion. Soldering has a place, but the automotive world, on wires and cables, it is largely unheard of.
My 150A alternator in my Falcon is wired back to the battery wiring with the same gauge wire as the main battery cables.
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