Replacing the salon fluorescent lights with LED - project write-up

Waking this thread up a tad..
John, I see from the pix that your LED strips appear to be 5050's. On a dual 18" fixture and two of those strips, is it really as bright as the tubes?

I have a test strip of 5630's that claim to be significantly brighter than the 5050, but they sure don't look like that will compete with the tubes. Am I nutz ?

Really need two of those strips per bulb in the long ceiling lights but if the light is say over a counter, two strips might produce good lighting. My 18" replacement florescence LED 'bulbs' only have one strip in each tube as far as I remember.

I tried bright white 5050s and didn't like them.  Then I tried soft white and didn't like them either.  Then my brain woke up and I tried alternating strings of bright+warm, one of each per bulb.  Perfect!  The only way you notice the difference is if you look directly at the LEDs.

The DW is happy, I'm happy.

awesome, John.  Appreciate the detailed writeup as well.  That's next on my todo list.  I also put a short strip of blue led lighting under the motorhome step when I redid the step motor and control.  Makes for a safer entry at night and is attractive as well. 

So you are running TWO strips per LAMP, total FOUR per FIXTURE? I have a roll of bright white that is a little too high up on the chart for me, and another roll of WW. That's 32' so I can double up and mix if needed. These are 5630 that according to the charts are essentually twice the output as your 5050, but can't prove it by me. These are vacuum and cleaning lights only, they are never otherwise used, so I need brightness.

You can always reduce the voltage with an adjustable voltage regulator or use a PWM dimmer if it turns out too bright.  I run mine at about 10.5volts.  Yes, two rows of 5050s per tube, four per fixture.

Yeppers Jeff, four strips in the 36" fixture. Like Muddy Paws mentioned you can buy one of those cheap Chinese buck/boost converters from eBay if you need them dimmer. I've used them for a couple of projects and they seem to work well.

Not necessarily grasshopper...

ALL of those dimmers control the negative side of the feed, not positive. That means that if you can find that return line at all it needs to control (ground return) ONLY the lights you want to dim. I ran into this in the bedroom when I converted the overhead lamps to LED then found out that the ground for those lights is also the same one for the shower and an overhead fluorescent.

I had to play some games with floating switching buck inverters and THEN a dimmer that I really don't want to do again because of the way the dimmer pot range lays out. Something I still need to figure out how to make less than 1/4t on the pot cleanly extend to a full range control on the bedroom dimmer. You're very limited working with negative control devices when the coach is wired as a common return and loops that wire around randomly where you cannot get to it.

Jeff - I wasn't suggesting you use a buck converter as an active dimmer, just to lower the voltage a bit to the strips. Come to think of it, I'm not sure what their current capacity is, might be too low for two strips.

The buck converters I used were so cheap and small I used one in each fixture, about $1.50 each.  No problems with effecting other lights at all.  The voltage regulators come in a variety of amp ratings.  No problems at all in that area.

I chose not to use a PWM dimmer because I'd have to find a place to mount it and they were all too big and at the time were known to generate a bunch of RF interference.

The problem is that LED dimmers control the negative, not the positive side of the circuit, check them out. The only way I could do this is with positive regulator in a to5 case and control the ground. That works but its just irritating that all these regulators are upside down. Since these are really service lights I may just wire them direct and go for full-on anywho.

One of the reasons for the buck was I am running no ballast so I want a hard cutoff on the LEDs to keep them from taking off.

If LEDs say 12 volts bear in mind that that's their maximum, and an RV system can be upwards of 14 volts.  I wouldn't build a LED light without regulators.

My strip lights aren't regulated and they are three or four years old.

You were lucky and got LEDs that have some extra voltage tolerance.  I wasn't so lucky.

I've purchased 3 different rolls of SM5050 LEDs and each one of them runs fine using a regulated 12 volts but when given a couple volts over they generated enough heat to be dangerous. 

Regulators are cheap.  Burning a hole in my RV (or worse) isn't.

LOL - I'd rather be smart than lucky! I'm probably going to replace them this winter with bright white, add a buck converter to each strip and tidy up my install. I've had the end of one of the strip lights come loose (two or three inches) and it's resting on the plastic translucent panel.

Get yourself a hot glue gun. 

I re-did mine so many times I got (almost) good at soldering the strips.  I originally bought the special crimp on connectors but after using them on my very first fixture and having most of the connectors fail I threw them away.  One little trick I picked up was that you don't need to solder the wires onto the end of a strip.  you can electrically join the strips together almost anywhere.

That's a good idea to use a hot glue gun. I've had super luck using double stick tape from I think 3M (Scotch?) - it's their heavy duty tape with a red backing.

I used the red tape too.  Didn't hold up, but that was when the strips were getting hot. 

Well I removed the dual 18" fluorescent, brought it home and drilled out all the rivets to drop out the ballast and sockets, leaving a nice clean white chasm for the strips. These are 5630 LEDs that according to everything I can find, are twice as bright as the 5050 LEDs. Even so I cut 4 strips of WW and 2 strips of the bright white. The bright white was way too purple for me as an interior light, even as a vacuuming light.

I ended up using 4 of the 5630 WW LEDs, and one brite white strip in the center on clip leads and took it back to the coach for a smoke test. I was completely underwhelmed and unimpressed at the results. Up against another fluorescent running WW tubes, it was TWICE as bright as the 4 WW LED strips as measured by an app on the iPhone that measures in Lux, pointed at the frosted lens of both fixtures (pix on request). I started to clip on the additional brite white strip I had added just as the other strips adheisive started falling off of alcohol cleaned metal... nice touch.

In the end I have removed the fixture and will reinstall the original fluorescents back into the fixture, it's just rivets. One more thing.. IF I were to add enough LED strips to equal the output of the fluorescents, I would also equal the current.. So what's the point? Maybe if I play games adding a boost regulator then back it off  to whatever the calculated current is I might get these LEDs up to the output I would expect, but it's not worth the effort. This test was done at ~12.5v. Mebbe if plugged in the results would be different, but I wonder.

Sure didn't expect this outcome..

SCVJeff said:

....In the end I have removed the fixture and will reinstall the original fluorescents back into the fixture, it's just rivets. .....

Click to expand...

Jeff - Nooooooo  :-\ :-\ :-\ :-\

I'll have to see what strips I used and get a lux app to measure the output on my lights.

Edit: I removed your double post.