Help me understand this kill switch wiring I found

Reposted from Reddit

Chassis is a Goth 3D eco with a removable battery, and a kill switch. No recharge port.

It has the standard high amp kill switch, located at the rear of the chassis right before the speaker.

There is a 22awg from the battery positive onto the left side pin, the center pin goes out to the board, and the right pin is cut off. Pretty standard right?

But why does it have another 22awg wire on the left hand pin running all the way back up, past the battery positive, to the NPXL connector?

Why not just run a wire off the battery positive to the NPXL connector and eliminate the extra 4 inches of wire?

Any thoughts?

Can you share a link to the actual image? I think i know whats going on but im having trouble visualizing it just by reading the description.

Hard to say without seeing it, but maybe the switch pin was easier to access or has more space around it and therefore was easier to attach two wires. Maybe the orientation of the battery positve tab meant that the two wires would have had untidy bends before heading off in opposite directions? Maybe the only way to wire up the battery positive was to glue it in first, but the installer wanted to reduce the risk of melting glue and plastic by avoiding the extra heat and duration of soldering two wires to it instead of one. Maybe the order in which the parts had to be fitted into the chassis made the extra wire run the easier option to actually make it work.

There are so many variables in lightsabers, and so many inter-related processes and things to consider when building them, that you sometimes end up with things that on the face of it seem illogical but have been done for very sound reasons.

Of course there are also things sometimes done badly because the builder was inexperienced, not great, or had made a silly slip up (we’ve all been there!) which they then had to rectify in a less than optimal way.

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That makes sense, I’ll have to visually take it apart when I get back to it and see if any of that applies. Thanks for the insight, I wasn’t thinking about it in those terms.

I was just curious if it had any benefit in doing it that way.

I don’t have any pictures of it right now, and I just put it all back together.

But basically, it looks like they just used one leg of the kill switch as a joint to go from the battery positive the NPXL connector. They made a U shaped spliced wire basically. I was just having trouble figuring out why.

Yeh it may be it’s not the most elegant solution, but sounds like he’s tried to avoid any bulky junctions, as they are often a pain in terms of space. I often use the neopixel connector itself as the positive splitter, so a 22awg wire goes from battery to neopixel +, then one of the other neopixel + pads has a 24 awg going to the switch, then the switch to the board. Because a hilt is so short, you have a lot of latitude in terms of wiring options because none of the cable runs are long enough for losses to become a big issue. :slight_smile: