Fixing a Fathom LED Fixture

[redfishbluefish]

I wanted to document the repair of a Fathom Hydra LED fixture. This posting will be a work in progress since I've just picked these up. I'm hoping I'm successful in fixing these. I do need to preface that I don't know what I'm doing.....I don't know electronics.....but I'm willing to prod on and figure out what's happening. I began by checking the manufacturer's website HERE. I found the information about the LEDs. Note, two rows of LEDs are not working on one side:




Turning on what I could turn on (above), and looking at the manufacturer's website, here's the layout of the LEDs in the fixture:



B = Cree XPE Blue 3 Watts x 4
RB = Cree XPE Royal Blue 3 Watts x 8
UV = Ultraviolet 415-420 nm x 4
WW = Cree XPG Warm White 5 Watts x 2
W = Cree XPG Neutral White 5 Watts x 6


So it is the blues and ultraviolets that are not working on one side.....a 3 watt circuit. The whites are 5 watt and all appear to be working. It was also noted that the fan did not come on when I turned on the fixture. Not sure is it's temperature dependent or just not working, so I'll have to take a look at that as well.

Next is to open it up, but I have one of my kids stopping in tonight for dinner.......

 

[dbl]

Good luck Paul with the repair. I'm sure you'll figure it out. Keep us posted.

 

[redfishbluefish]

Opened up the fixture and here's what I found:

Fan - Fan is an 80 x 15 mm fan spec'ed at 30 v, 0.04 A.....what?




No voltage was being supplied to the fan, so I'm going to hope it's either power or temperature controlled. In doing a quick search for replacements, nothing....not a single 30 v fan came up, and putting in the manufacturer and model number....nothing at 30 volts. So I'm going to continue to repair the fixture and wait and see what I have with the fan once all repaired.

LED's - On the LED side, I pulled off a couple lenses and found what I'd consider regular beads for the UV's (D2 and D5)(very easy to replace) and tiny little squares for the blues (D4 and D6).




I've never seen these little square LEDs available without being attached to a disc. Hoping I don't have to replace them. Not even sure where I could buy those.

When checking voltage, found about 10 1/2 volts at D5, but nothing at the other exposed LEDs. I'm assuming series circuit....and sure enough, when I jumped D5, all the other LEDs lit up! Could it be that easy?

I sourced the 415-420 LEDs out of China and ordered up 10 chips. Now just have to wait for that slow boat from China to continue this journey. I'm now hoping the other fixtures I have also simply need this one bead replaced.

Cleaned up the fan and put the fixture back together because I figure it will be 3 or 4 weeks before the new LEDs arrive.

 

[redfishbluefish]

Opened up the second fixture and found the exact same thing.....D5 UV LED was toast. The fan in this fixture, like the first, had no voltage being supplied. Again, hoping that is a power or temperature controlled fan. So I have a couple questions that I'm hoping the experts can answer:

1. What would cause the first LED in this series to no longer work?.....The D5 UV LED? Why that one? (FYI, I have maybe seven more of these fixtures that have the same appearance.....two rows not working....to me, suggesting that the D5 (first LED in the series) is shot.)

2. Why do the UV LEDs have a "milked"/ textured lense? Why not clear like all the other LEDs in this fixture? My guess is either UV direct is too much, or the textured part causes the UV to scatter all over the place.



EDIT TO ADD:

Just answered my own question....number 2....they are scatter lenses:

 

[redfishbluefish]

Replacement LED's arrived today from China and I went to un-solder the old LED. Even with my soldering iron set to the highest setting, couldn't get the old one off. Looking closely, I didn't even notice solder. So I'm figuring that these must be glued in place. I then started prying the old LED and ripped it apart to get it out....sure enough they must have used thermal GLUE. Here's the destroyed LED:




So I cleaned up the spot and used Noctua NT-H1 thermal paste and soldered the new bead in place. The new bead was labeled + and - , so that made the install easy. And here's the best part.......it worked!





I am concerned about the other fixtures I need to fix and removing that glued LED. This is the first time I've pulled out a glued LED. Does anyone know if there is an easy way to remove them. I actually pryed this first one off using a large heavy duty knife.

 

[kschweer]

Replacement LED's arrived today from China and I went to un-solder the old LED. Even with my soldering iron set to the highest setting, couldn't get the old one off. Looking closely, I didn't even notice solder. So I'm figuring that these must be glued in place. I then started prying the old LED and ripped it apart to get it out....sure enough they must have used thermal GLUE. Here's the destroyed LED:




So I cleaned up the spot and used Noctua NT-H1 thermal paste and soldered the new bead in place. The new bead was labeled + and - , so that made the install easy. And here's the best part.......it worked!





I am concerned about the other fixtures I need to fix and removing that glued LED. This is the first time I've pulled out a glued LED. Does anyone know if there is an easy way to remove them. I actually pryed this first one off using a large heavy duty knife.

Nice work Paul!!!

 

[redfishbluefish]

Thanks Kevin....I really wish I knew what I was doing!!!

I opened up the second fixture and this was most bizarre. Solder was definitely present. When looking through a jeweler's loupe, I could clearly see a negative sign on the positive side of the LED. What's going on there??? I attempted to take a picture through the loupe and here's what I got.....note the " - " in the yellow circle:




Now what little I do know, this wouldn't have worked from day one. An LED installed backwards won't work at all. I don't get it. I was under the impression these were working.....originally from the manufacturer....and never touched. How could this work at one time with the LED in backwards?

I tried to remove this LED without destroying it, but couldn't do it. Interestingly, I took a close look at the first one I repaired and now believe that one was also installed with the negative side of the LED bead attached to the positive side.

Anyway, the new LED went in and this fixture is now working. Two down.....I think seven more to go.

 

[dbl]

I knew you could figure it out Paul...nice work, even through the confusion!!!

 

[kschweer]

Interesting stuff. I think you're doing great for "not knowing" what you're doing. I'm completely clueless when it comes to stuff like this. Does fathom still make lights?

 

[redfishbluefish]

...........Does fathom still make lights?

That's a good question. The link I included in the OP would certainly suggest they are still around. It would appear that you could still purchase directly through the site. However, in doing searches on this fixture, the only newer posts I could find on various fish sites were for people selling their fixtures. The best I could find out, they are a small local company (I believe NYC) and the guy would come to your house to set up your fixtures. On another NYC site they had their own "area" that is now gone. So again, I'm not sure if they are still around, and if so, no one is talking about their fixtures. Just look at the lack of response in this post.....I don't think many people own these lights.

I will say one thing, in their heyday (2012-13), you'd hear nothing but great raves about this fixture....in the appearance of the corals popping and the amount of growth.

 

[redfishbluefish]

It is now quite clear that the UV LED beads are the weak link. I had heard this before. Fixed two more of the fixtures this morning. Fixture #3 had UV bead D2 blown.....replaced and now works. Fixture #4 had both UV beads D2 and D5 blown....both replaced and that fixture now works. It was also very obvious that fixture #4 had these two beads replaced before.

As far as the company still being around, it's looking more and more like they aren't around anymore. It's a shame because the quality of machining and apparant electonics is quite impressive.....and reports that they were excellent in appearance and growth of corals. On R2R, FathomLED joined in June 2012 and was "last seen," November, 2013. I've also heard rumor that the owner became ill and needed to close down the business.

Now I wish an LED or electronics expert would look at this post. The question I have, with these 3W UV beads being the weak link, could they be replaced with say, 5W UV beads, and the fixture still work? And, would this 5W UV bead be "stronger" and ideally last longer? I just don't know electonics. To rephrase the question, would two 5W beads in a series with six 3W beads work, and would it be a benefit? I think Todd ( @twilliard ), is an electronics guy, maybe he'll know.

 

[twilliard]

Hi Paul!
The UV chips are harsh on everything especially the optics. These are typically the first to go. Much discussion with orphek schooled me on that one LOL
You can wire in the 5w chips but you have to do the calculation based on the voltage (output) of the power supply. Also what is the mA is the driver? I am sure the manufacture did not max out the drivers.