Outdoor RGB light setup - Some safety questions - Page 1
Forum section: electronics / beginners

author: ndictu
author_rank: Regular Contributor
timestamp: November 22, 2021, 06:43:26 pm
content: Hey folks,I'm planning to set up some outdoor RGB lights with Arduino control as xmas decoration. I'm comfortable enough around basic Arduino stuff but this time I'll have to deal with some higher currents and dedicated power supplies due to larger power requirements and I want to make sure I'm not about to do something stupidWhat I ordered:- Arduino Uno Wifi (5V supply & 5V logic)- WS2812B RGB LED strips, 5V, 60mA per led, rated IP67- A 5V 20A power supplyMy plan:- Cut up the LED strips into ~2.5m pieces (roughly what I need). With 30 leds/m and 60mA/led that gives me around 4.5A max current draw.- Take four such strips, wire the power inputs in parallel using thick-enough wire to the PSU. That should stay well below the 20A limit, and of course I won't light up all the LEDS to full brightness at once anyway.- Use the same supply to also power the Arduino, wire up one signalling line per strip to the digital outputs.- Heatshrink every connection, stuff the Arduino+PSU into a waterproof box with wire glands to protect it from rain.Seems simple enough, right? But I do have a few questions:1) While testing / programming: Can I just plug in the arduino via usb to my computer? Do I need to worry about the PSU output not being properly grounded or stuff like that?2) Do I need some extra fusing on the 240V input to the PSU or anything else? It is one of those sheet-metal cheapo PSUs.3) Anything else I'm not even thinking of that will cause me trouble?

author: RJSV
author_rank: Super Contributor
timestamp: November 25, 2021, 06:04:44 am
content: (Keeping in mind, I've often been very critical, of 'consumer product' quality, please don't take offense).When I read terms used, like: "...stuff like that...",not too impressed, especially in same paragraph, with safety concerns.However, I'm no big genius, when it comes to (proper) device grounding: it's often confusing.I can address some of this. For outdoor use. Uh, that 20 amp DC supply, likely a bench top application ? Indoor use ? OR, is that a supply rated for outdoor conditions?Right away, I can visualize, some power supply plugged in, in garage or shed closet. Cables running, dogs, lawn sprinkler hoses, dogs and really 'chewwy' puppys... So, I'm thinking about the whole of this, not just one device. Using 5 volts, certainly inherently can be safer. That's some heavy Guage wire, I guess.Heck, even running the cables, has some tripping injury hazard. But keeping the mains voltage portion back inside somewhere dry, inside the garage, that keeps hazard contained.Industrial settings probably more strict, about much much more, but you have to consider, maybe can't control who, (young children / dogs), who aren't thinking 'safety', in back yard, there.My best suggestion, keep aware of cable runs, for avoiding trip hazard. Plus, take time in placing that power supply box, (not just set on top of washing machine, etc.)

author: m k
author_rank: Super Contributor
timestamp: November 26, 2021, 09:15:23 am
content: Around here xmas lights have been drawn back because their cables have been stamped with better values than the cables actually are and some fire hazards have happened.