Hopefully this is the right type of place to post this.
I followed this instructional video to make a Home Assistant controllable light strip: The BEST Digital LED Strip Light Tutorial - DIY, WIFI-Controllable via ESP, MQTT, and Home Assistant - YouTube
I'm new to this sort of thing so I found it quite tricky but I got it to work eventually and it looks great.
It's wired as per this diagram.
I purchased an LED strip IP67 rated but it turns out it's not because it's shorter strips soldered together and the solder joining the strips is exposed on the rear.
I have the strip mounted outside which is completely exposed to the elements. I've tried to use a decent amount of glue around the parts that are exposed to seal it and I've sealed the 12v wire to the strip as best I can but it's not perfect and could also degrade in the weather. The strip is powered by a 240-12v 5A power adapter which is plugged in inside.
Is there a risk that if water got into the circuit and it short circuited that a fire could start at the power adapter? I'm hoping it would just stop working and I could replace it but even the possibility makes me nervous.
I was thinking of installing a fuse near the adaptor on the 12v side. How would I calculate the fuse size and is this something that would help?
That's always pretty hard. See "water proof" as splash proof. If it's protected from direct water it should be fine.
did you try heat shrink (maybe even the kind with glue in it)?
Might be, you have 100W of power.
You pick a size determined by the normal load. So what is the normal max load? Aka, what strip, length and do you use full brightness?
You should have done this in the first place to pick a proper power supply
And I would turn off the 12V to the strip if you don't need it to be lid. Can be done with a mosfet. Again, you need to know the current.
The most likely outcome is electrolytic dissolving of the conductors if moisture gets in. The best way
to seal for outside conditions is proper potting compound in a plastic box, but I guess these connections
don't have much space around them. Perhaps glue-filled transparent shrink-wrap tubing is a reasonably
robust and weatherproof method to join the strips.
I have a couple of thoughts that might be useful:
- Is you power supply current limited? Many power supplies will protect them selves from over current and over temperature.
- What is the current of your strips? If much less than the 5A of your supply a fuse might be a good safety precaution.
- Surface corrosion between the 12V and common will likely cause a local resistance that will be destroyed by the resulting current.
- Usually I suggest RTV but it may not be compatible with the glue you have already applied. If you do try RTV do not use the type that releases acetic acid during cure (i.e. smells like vinegar)
If the power supply is from a reputable manufacturer and has [u]UL Apprived[/u] and/or other regulatory approval, there is little chance of a fire if something "goes wrong".
But if you bought the cheapest thing you can find in eBay or Alibaba...
Thankyou for your prompt replies, sorry I couldn’t get back to you sooner.
I worked out the Amp draw of the circuit as follows:
Standby - .25A
Normal Operation - 1A~
Max draw - 2.2 A
Not quite as much as I initially calculated (Just under 5A) but I suppose that’s a good thing.
DVDdoug, you’re quite right, I did buy the cheapest thing I could find on Aliexpress (see picture)
It doesn’t seem to say anything about UL Approved, but it does say a lot. Do you think it’s wise investing in a UL approved adapter?
I’ve weatherproofed it as best I can using heatshrink and silicone.
So I’m thinking a fuse next to the adapter. I guess I need to find a fuse closest to 2.2A? Do I put this on the positive or negative side or does it not matter?
The comment in relation to the mostfet to turn off the 12v to the strip is a good point. Unfortunately the way I’ve wired it up, I would need to pull the whole thing out to do this (and it took me nearly a whole day to put it in re the conduit, soldering etc)
Any other thoughts would be appreciated.