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I am installing an Eaton CHSPT2ULTRA surge protector to my Siemens QP breaker box.

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The surge protector has (4) 14-gauge stranded wires to connect. I had no problems making a tight connection with the green wire to the grounding bar, and to the white I added some stranded 10-gauge wire with a wire nut to reach the neutral bar, which is secured tightly.

The problem is that the black and red wires connected to the 50 amp breaker don’t seem too secure. If I tug on the wires somewhat they don’t come out, but I think if I pulled harder I could pull them out of the breaker without too much effort.

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Taking a close look at the 50 amp breaker, it’s (of course) made for a much larger (8-gauge) wire. Even with the screw all the way tight, there is still space at the bottom of the screw. So it seems to me that the 14-gauge stranded wire just isn’t big enough for the breaker screw to hold the wire tightly.

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What is the best way to fix this loose connection at the breaker?

  • Can I use crimp-on spade terminals to the two breaker wires? Is it up to code to have this connector inside a breaker box? Gardner Bender makes a 16-14 AWG 4-6 Stud Spade Terminal, Vinyl Blue (10-Pack) that is rated for 600-Volt maximum rating as building wiring and 1,000-Volt maximum rating for signs and fixtures, and has UL and CSA safety listings.

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  • Is there a better way to do this?

Thank you!

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    Isn't the problem that you shouldn't use a 50A DP breaker with those 14AWG leads? What size of breaker does the surge protector say you should use? Commented Apr 2, 2021 at 21:38
  • I stand corrected. From the product manual: "Locate a dedicated unused, or install a new 2-pole circuit breaker in an available space closest to the location where the CHSP is to be installed. A dedicated 2-pole 15 ampere circuit breaker is recommended for use with CHSP devices, but use a 2-pole 50 ampere circuit breaker to achieve the full published ratings of the CHSPT2ULTRA device. (The connecting wires do not carry supply current. Instead, they carry only short-duration currents that are associated with a transient event.)" Commented Apr 2, 2021 at 21:40
  • Completely unrelated - I don't understand how this surge protector can protect from surges if its off the side of the distribution board, rather than in-line with the incoming supply feed. I've asked about this in Home Improvement Chat because its not a real practical question. Feel free to chime in over there.
    – Criggie
    Commented Apr 2, 2021 at 23:08

2 Answers 2

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You are correct in addressing this, but the ring terminal isn't the right tool for the job

You are indeed correct that 14AWG is well outside the listed/labeled range of the lugs on a 50A Siemens QP breaker -- they're rated for 8AWG through 4AWG wire only. However, nobody's tested them with ring tongue terminals either, so your ring terminal solution is off base. What I'd do instead is use a short length of 8AWG stranded THHN and an appropriate wirenut as a transition pigtail to adapt the 14AWG leads on the CHSPT2ULTRA to a wire size your breakers are rated to accept. (If you insist on doing this using crimped connections, you can use a suitable closed-end crimp splice instead of the wirenut, as doing the transition with a butt/in-line splice requires a special reducing splice connector, the Panduit ESV8-ESV14-Q, that isn't a hardware store item.)

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  • Even though the reducing splice connector is a neater solution (but also costly & hard to get), I think I'll just do the wirenut to a short 8AWG wire into the two breaker screws as you suggested. Simple, easy, and I can do it today. THANK YOU!.
    – Jim Smith
    Commented Apr 2, 2021 at 16:56
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The type of screw terminals you have never makes reliable connections to stranded wires, the strands tend to come out and squeeze out when thermal cycling. Even with solid wire it needs to be thick enough to fill the hole, or it can wiggle around and get out.

If you want to use stranded wire with screw terminals, get a hexagonal crimper for $20 on aliexpress:

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Get your crimp ferrules:

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Thread, insert, squeeze...

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This does not solve your small wire in big hole problem though. For that I'd use a 8ga crimp ferrule since that's the size that goes with the hole, stuff it with enough stranded wire to fill it (including the wire from the surge protector) and crimp the whole thing.

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    "stuff it with enough stranded wire to fill it" needs code citation verifying legality.
    – FreeMan
    Commented Apr 2, 2021 at 18:08
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    DV since this violates the breaker's listing Commented Apr 2, 2021 at 18:17
  • @ThreePhaseEel Yeah, what would happen to the very thin wire connected to the surge suppressor if there is a short in the device and it is connected to a 50A breaker?... I've looked into the manual, and the device comes out of the box with these wires sticking out. There's even an excuse "it's only for transient current"... hmmm
    – bobflux
    Commented Apr 2, 2021 at 19:22
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    @FreeMan If there was an electrical code in the US, twisty wire nuts wouldn't be legal on stranded wire ;)
    – bobflux
    Commented Apr 2, 2021 at 19:24
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    @bobflux -- the issue is that panelboard-type breakers aren't tested, listed, or labeled to be used with ferruled wires Commented Apr 2, 2021 at 21:21

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