protection
Transmission lines have protection systems to protect themselves from lightning strikes, but in the case of a strike hitting a line under test – how is the user protected?
I'm looking for an answer in the scenarios of a strike hitting the line 20 miles from the engineer, and a strike hitting the line under test directly at the engineers location? – if there is a difference in these scenarios of course.
Wire capacitance at such current is negligibly small. Don't worry about this at all.
According to wikipedia - typical AWG 20 wire resistance is 33.31ohm/km.
With 8m distance current travels 16m of conductor total (there are 2 lines/cores in wire). 0,016km * 33 ohm = about 0,5ohm At 1A current you will loose U=I*R = 1*0,5 = 0,5V
Maybe use a bit thicker wire to reduce voltage/power losses? Additionally - resistance differences will dim your "far leds" more than "closer leds".
Long unshielded wires with few Amperes PWM signal will emit some EM indeed, and you may hear it in your audio equipment. To aviod that you may put transistors at leds, and use 2 wires - one coaxial for just PWM signal and AWG for power. At the end of power wire and before transistor put electrolytic capacitor to reduce EMC noise emitted by power wire. Like this (thats just idea visualisation):
You have very small inductance there, you don't need flyback diode.
Sorry if I did some language mistakes, my english is not perfect.
Overview:
A good wrist strap system has a large resistance between the skin contact and ground. Typically this is 1 MΩ, which is relatively large. This large resistance is there for your safety, in case an error somewhere connects you to a hazardous voltage. Even this high resistance is sufficient for protecting your devices from ESD.
A typical multimeter should be able to measure this resistance. However, most continuity tests will probably report it as open. This is because many continuity functions are looking for resistances less than 100 Ω.
Verifying your wrist strap:
Here is how you measure your wrist strap system - check from the skin contact side of the strap (red meter lead) to the part that gets connected directly to ground (black meter lead). Make sure your meter is configured to measure resistances higher than 1 MΩ, as the resistor will not be a precision tolerance. Note that in this picture I am making sure I don't touch any of the metal surfaces, which would give a bad reading.
Measure the resistance from the inside of the wrist strap to the outside or the end of the cord. Make sure you're on the high resistance scale of your meter if it does not auto range.
In the labs I work in, the resistor is in the actual lead somewhere (the black wire). On the snap housing it is marked as 1 MΩ, and all the wrist straps are low resistance connections from the skin side to the snap connector. I have seen ESD straps with a 1 MΩ resistor built-in.
Don't use the continuity test:
For kicks and giggles, here's the result when you use the continuity check function on the whole thing - it reads as an open circuit (no continuity). With my setup, I would expect the meter to beep/show continuity on the wrist strap, but not on the wire lead.
Conclusions:
Without knowing if the reviewer just used a continuity test, or actually measured the resistance (or even where they measured), it's impossible to draw any conclusions from the review. If the reviewer knew how to properly measure the system, then I would consider that a defective product. If the reviewer tried to use a continuity check across a 1 MΩ resistor, then the reviewer is not being helpful at all. The wording of the review makes me suspect the latter, but it is impossible to know from what was written.
Best Answer
There is extensive training for safety which would fill a book.
1) Insulation. > 4 meter fiberglass rods for moving live lines with hook. Tools cleaned daily. Insulated Bucket truck lift. Safety arc flash gear. Double insulated boots etc .
2) Earth bonding mobile equipment
3) Overhead protection
Meanwhile USA has that many death by firearms every week.
Anecdotal
Last year I was at the Coral Castle in a rain storm in Florida, the lightning capital of North America , our guide was too afraid to take us outside. So I asked him, has there been any recent reports of power interruptions or worker deaths? He said No but still wouldn't go out. I said see those little antenna at the top of every wooden power line pole. Its an earthed tungsten sharp tip that acts like an antenna above the trees. That's why.
Some are coiled which slows down the current ionzation but reduces the induced voltage. The best are short sharp tungsten tips on top of every pole well bonded to earth to bypass the structure.
There are still risks and more details to cover, but this gives some idea.
We went out in an umbrella surrounded by the castle and much taller poles along the street closely spaced with lightning protection. Every city does not do this, but in Florida it works. They need it.