I was wondering if I properly crimp using ferule crimp connectors and I solder the copper within the crimped ferule would this not be the same as solid copper wire? When it comes to mechanical lugs or the screw down type used in a circuit breaker what would be the difference in solid copper wire let's say 10 gauge vs 10 Gauge stranded copper wire with a ferrule crimp connector soldered together, is this code compliant?

I am located in Florida.

  • 4
    Why are you even asking this? What make and model is your breaker panel? Commented May 27 at 3:30

3 Answers 3


In theory, that is all true. In reality:

  • Unless you are really good at soldering and prepare everything just right, you will end up with a high-resistance connection. That may be OK, or it may overheat. That is particularly a concern with 10 AWG wire. Why? Because at least with 14 AWG (15A) or 12 AWG (20A) circuits you might really be using just a couple Amps and not have too much to worry about. But nobody uses 10 AWG unless they are really expect to use at least 16A (80% of 20A) continuously. In fact, typical 10 AWG wire on 30A breaker is for a 19A - 24A continuous load such as a water heater. Even just a little extra resistance will create a lot of heat. Not a good idea to try that.
  • Breakers and other devices (e.g., receptacles) are normally designed to handle stranded wire without a problem. So this is a lot of work for no real benefit.
  • If you happen to have a device that can only use solid wire, just get an appropriate UL or ETL listed wire nut. For example, most Ideal brand wire nuts and In-Sure Push-In wire connectors list exactly what size solid and stranded wires they can use. For example, an In-Sure Blue is rated for 30A, #14 - #10 solid and #12 - #10 stranded. The Twister Wire Connectors specifically mention "solid-to-stranded" and 341 Tan should work fine. Many other options, and that is without even looking at other brands of connectors.

So if you have any concerns about stranded, just get a short piece of solid wire, same size, same type (copper presumably - don't mix copper and aluminum unless you absolutely must), same color family (e.g., black or red or blue or orange or yellow for hot, white for neutral) and a good connector and you're all set. Leave the soldering iron for low-voltage projects.

  • 3
    Even in theory, soldering wire ends that go into screw terminals is a really bad idea. Solder is too soft and not "springy" enough to go back to its original shape after it heats up due to the flowing current and cools down again. Instead, the heating cycles and the clamping force will gradually make the solder yield and flow away, eventually increasing contact resistance (= a fire risk). Ferrules are the way to go if the terminals are rated to accept them and not rated for plain stranded wire, but I have never seen terminals rated for soldered stranded wire (at least not here in the EU).
    – TooTea
    Commented May 28 at 8:13

Every terminal in your breaker panel is already UL listed for stranded wire. Just groom the strands and give them a twist so they stay together.

I use almost exclusively stranded, and I don't do anything special.

You must torque all breaker panel terminals to spec. The spec calls out a torque for solid and stranded wire. It doesn't call out any torque for a stranded wire crimped with a ferrule and soldered. The manufacturer and UL would say "Don't do that, we haven't tested for that".


solder the copper within the crimped ferule would this not be the same as solid copper wire?

Most of your questions fall under NEC 110.14(B) "Conductors shall be spliced or joined with splicing devices identified for the use... Soldered splices shall first be spliced or joined so as to be mechanically and electrically secure without solder."

In other words, it's only code compliant if your crimp connector is listed for 10 gauge 120 V electrical splices and for the number of wires being crimped.

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