by /u/SuperAngryGuy of /r/HandsOnComplexity
As a (former) electrician for 10 years who went through a 5 year union apprenticeship program and a hardcore electronics geek, I want to give a few safety tips because I've seen some stuff that's got my spider-sense tingling. Everything is done at your own risk and liability. I just want to minimize that risk.
Use a GFCI!
GFCI protects you from ground path faults
That's Ground Fault Circuit Interrupter. You have electricity and a lot of moisture: that could be a bad combination. GFCI protects you from ground path faults. In other words, it prevents serious shocks from the wall power supply, through your body and to ground. Literally, this means a ground path to earth itself or a ground path to an object at ground potential. Twice I've had GFCI protect me from being severely shocked. You'll still feel a slight tingle but that's it. No dying, though. How cool is that! GFCI does not protect you from hot and neutral wire shocks because it only shuts the circuit off if there's a current imbalance between the hot and neutral wire. If there is, it means current is going to ground when it's not supposed to. That's bad- it could be going through your flailing and thrashing body. A GFCI circuit does not require a ground wire to work. GFCI can be found in breakers, receptacles, power strips or adapters. How much is your life worth?
Wet concrete floors are bad! Get them off the floor and get yourself off the floor. It's just another safety thing to keep in mind. Wet concrete has a bad habit of conducting electricity. Play it safe and think of wet concrete as standing in a mud puddle from an electrical safety stand point. This is why it's a good idea to have GFCI protection in garages.
Sockets need to be wired the right way
I don't care if it is just two wires. One is the hot (black) and one is the neutral (white). If you have a brown and blue wire, it's almost always the case that the brown is the hot and the blue is the neutral. You'll see this in some appliances and extension cords depending where you live in the world. If the socket has pig tails (it's own wire sticking out), it's always hot wire to socket black wire and the neutral wire to the socket white wire. NO EXCEPTIONS! If there's screws instead of wires, the brass/gold colored one is for the hot wire and the silver colored one for the neutral wire (more below on this). Why is this so important? Because when you screw in a bulb there might be a little metal exposed at the bulb's base.
Wired backwards and you have an energized metal part exposed (bad). Wired correctly and you have a exposed metal part at ground potential (better). Wrap any exposed with a little tape and you have very good. If you have a lighting socket with 2 of the same colors coming out, the neutral will be connected to the socket side threads, the hot connected to the metal piece deep in the center of the socket. In this case you need a continuity tester or multimeter to determine which wire is the neutral.
Splice wires correctly!
Wire nuts are easy and safe to use
With Space Buckets you're going to run in to situations where a junction box may not be able to be used so here's some open air splicing tips. If you can pull the wires apart then you have a bad splice. The preferred way is using wire nuts. Strip your wires 5/8ths of an inch, put them in the opening and twist until you can't anymore. There's a spring inside that tightens the wires together. It's not necessary to twist the wires first. You should, however, tug on each wire to make sure it's well connected after the wire nut is twisted on. Tape the wire nuts up. You should so no exposed metal parts from any angle.
The second way is a butt splice. They’re sometimes called splice crimps. Strip wires, stick them in and use pliers to crimp the aluminum tube inside as hard as possible. There are special pliers for this but any pliers can do. Again, tug on the wires to make sure they're secure and tape as needed.
The third way is tape and solder. Twist the wires in a rat-tail splice, solder them up and use a higher quality electrical tape preferable Scotch Super 33+ to wrap them up. 33+ has an adhesive that hold under a wide range of temperature and humidity. Low quality electrical tape has a bad habit of becoming undone at higher temperatures and humidity. Twist and tape alone is not recommend for line voltage splicing. The same with a T-splice unless tape and solder is also used.
Secure those wires!
This means additional stain relief and to preferably use tie wraps to secure the wire to the bucket's lid. Drill 2 small holes just big enough for the tie wrap and secure the wire to the lid that way. Sticky backs can also be used. Use some 5 minute epoxy if needed to secure the sticky back. Even it everything feels snug, it may actually be 1 or 2 out of 3 that are snug. Loose connections means fire. Push the male prongs together to the point that you have to do a little wiggling to plug something in. This is really more critical wire higher current loads like electric space heaters, HPS lighting and the like but a good habit to get in to.
Never use line voltage at canopy level! If you use LED intracanopy lighting, use a lower voltage to drive them.
If using foil as a reflector, ground it
With three conducts you'll typically have a black, white and green (or brown, blue, green or green with a yellow stripe depending where you live). That green wire is your grounding wire. Metal parts should be bonded to this green wire.
You can use a screw/nut/washer through the bucket side, through the foil and put the green wire under the washer preferably with a fork terminal stake on. If you're connecting wires to a light socket with the gold/silver screws mention above, this is the preferable way to connect the wires. Put tape over the screws with some 5 minute epoxy to make sure the tape stays in place. The best inside the bucket reflector is flat white paint with barium sulfate added. It'll be in the high 90% range.