Solar Panel Security

[The Short Short Trailer]

PART 1

Hello All,

This post pertains to securing my solar panel from idle hands. The solutions I suggest will not stop a determined thief but will be annoying enough that things will probably stay put against the casual opportunist without tools. I bought my materials through McMaster-Carr. It is, by far, my favorite website because the search mechanisms are so helpful. Supply is great and delivery is fast, but it does come at a premium. If you have time and like the hunt, I am sure you can find all of these materials more cheaply at other suppliers.

Basic Theory:
Goal: lock my panel to my trailer via a steel cable.
Problem: I don't want to see (or trip over) additional cables and clutter in my camp site.
Initial Solution: heat shrink my 15' power cable and the steel cable together into one bundle. Loop and lock ends of the steel cable to my bumper and to a drilled hole in the solar panel's frame. Much cleaner (visually and physically). I considered just cable-tieing them together but campsites are often dusty/sandy and I didn't want to stow a bunch of extra dirt between the cables.

Here are the materials I bought:
__steel cable
__combination locks
__crush sleeves (for making loops in the cable ends)
__roll of heat shrink tubing

Here are most of the tools I used:
__heat gun (or a candle might work if you're VERY patient)
__tape measure
__electrical tape
__drill driver
__#2 phillips screw driver
__pick
__scissors
__vise
__two small drill bits, roughly equal size, at least one larger than the loop on your lock.
__(I wished I had a fish tape for threading the cables)

Up next... Fabrication Process.

 

[The Short Short Trailer]

Part 2

Fabrication Process:
1. Measure your solar panel's cord. Mine was 15'.
2. Add at least 2' to your cord's length and cut your steel cable to length. (I added 16" to the trailer end and would definitely NOT go shorter. By the time I added my loop and wound once around the bumper it was snug. 8" at the panel end was fine).
3. Record the correct wiring positions and remove one end plug end of your cord. (This assumes you have a removable plug end, not a molded one).
4. The hard part: feed the cable and cord through the heat-shrink tubing. This is where I wished I'd had a fish tape. After much ridiculousness and several different strategies I ended up cutting my tubing into two lengths and overlapping them in the middle. There's more I could say about this but if you get this far, message me and we can preemptively commiserate.
5. Make loops in your cable ends. The crimping tool is over $200. Here's my workaround:
5A. After looping your cable through the sleeve, tape two small drill bits on either side of the fitting.

5B. Then use your handy vise to crimp away. Just think of all the fun things you will do with all the money you just saved. If you don't already own a vise, go buy one... you'll use it a lot more than the crimping tool.

6. Heat shrink. 15' of heat shrinking will take a long time to shrink with the wrong tool. I strongly suggest borrowing one if you don't have one. Your local auto parts store may lend you one for free. I've previously used flame for short runs. If you are careful and patient a candle might do the trick.
7. Re-install your plug end.
8. Drill a hole in your panel frame.
9. Set the combinations on your locks.
10. Test the fit.

Up next... Summary

 

[The Short Short Trailer]

Part 3

Summary:
Here's the fit at the trailer end:

And the panel end:

Secondary Solution:
One night after all of this I realized if the goal is to make it hard for someone to simply walk off with the panel, the power cord alone might serve the same purpose. It won't be 100% as secure as with a steel cable but it would be very easy to implement with only two padlocks. As long as the head of your plug is too large to fit through the loop of your lock, no one is walking off with your panel without cutting the cord or lock - and that requires a motivated thief outside the scope of this design.

For example (it works through a drilled hole in the panel frame, too):

I hope these simple options help make trailering even more relaxing.

Cheers,
-Ken

 

[Randy]

Brilliant!

 

[Van_and_Terri]

Great solution and illustration. Thank you!

 

[Tour 931]

Thanks for the posts. I don’t have solar panels but will someday.

 

[rotus8]

Great idea.

For feeding the cables through shrink tubing, it helps to pull rather than push. I put a string through the tubing, pretty easy using a shop vac to suck the string through. Then tape the string to the cables and pull.

You can feed the cable through the loop on the end after wrapping around the bumper. Then you only need one lock. You do need to make the cable long enough for this to work.

 

[Tour 931]

Great idea.

For feeding the cables through shrink tubing, it helps to pull rather than push. I put a string through the tubing, pretty easy using a shop vac to suck the string through. Then tape the string to the cables and pull.

You can feed the cable through the loop on the end after wrapping around the bumper. Then you only need one lock. You do need to make the cable long enough for this to work.

Brilliant!

 

[Lane and Michael]

What a great way to crimp the cable! Might even get away with Vice-Grips if you don't have a proper vice.