actinic pc end cap melted...

[rtgordon]

I was lifting my canopy to do some work and my actinic bulb went out. It's only a couple of months old. I started looking and the end cap came off in the harness. I tore it up getting it out. It was pretty stuck.

What happened? Did it overheat? The canopy is open in the back and about 4-5 inches away from the wall to accomodate the HOB filter and skimmer. I assume that I can just go get another bulb and endcap. Any idea what they run? Should I consider any upgrade (if there is such a thing) from the standard actinic?

I put a pic to show what happened. Any suggestions as to what to do are appreciated.

Thanks!
gordon

[ruhspolostar]

it seems like when they get old, they tend to diseegrate, especially being around SW

[rtgordon]

Originally Posted by ruhspolostar

it seems like when they get old, they tend to diseegrate, especially being around SW

it is brand new

[Eric P]

I have had this happen to me also. It seems that if the pins don't fit tightly together when they are new or they aren't pushed in all the way, they get hot and melt the plastic. I will no longer be using pc's for this and other reliability and high cost reasons. It's back to vho for me...

Eric.....

[jesspaul]

I would say the endcap was faulty to begin with and was overheating. Might have been a bad joint in the wire with a poor connection.
BTW VHO's get pretty hot too! There are a couple of small indentions in the tank rim where the bulbs touched till I fixed the canopy.
I have a question! Does anybody use any thpe of greese on their endcaps or sockets for keeping the salt and water out?

[yardboy]

The endcaps on my PC's are waterproof and have never gotten salt or water in them. As do my VHO's, though they can be kinda tricky to remove after they burn for awhile due to the gaskets sticking to the bulb. Might also be due to my metal halides being pretty near.

[Eric P]

Jesspaul, I don't use anything on my endcaps. There are a number of reasons that I prefer vho to pc.
1: reliability. I have had some problems with my pc systems. (I have had 3 systems, 2 have had major failures.)
2: VHO actinics have a better color IMO.
3: Bulb repacement cost. My pc's have been costing almost double.
I agree vho's get as ho or hotter than pc's. They both need fans imo.
For some folks pc may be the way to go but for me it's back to vho. I would look into t5's but I am only using the flouro's for actinic suplementation, mh for daylight.

JMO, Eric...

[Ryan Mackey]

The strange thing is that if it were heat that caused the failure, the rubber would have melted and curled prior to the base plastic on the bulb. Also, the plastic looks to be fractured and not "cooked" by heat. Does the rubber boot AKA "humid location endcap" show any signs of melting? Does the base of the bulb? This looks more like a case of mechanical failure either from impact or explosive failure, or perhaps an unseen crack in the bulb base when purchased. We have more problems with PC bulbs than VHO, but they are run a little harder than VHO. PC technology has come a long way, but for us, we like the VHO actinic enough to avoid PCs in many set-ups. Ryan@advancedreef.com

[rtgordon]

There wasn't any melting. It seemed like the metal pins were "glued" in. I assumed it was from heat. It is a possibility that it was really tight (for some reason) and the cable was stuck on something when I opened the canopy. *shrug*

Thanks for the replies. It doesn't look like a wire/harness issue, does it?

I know more about pc's now than when I bought the system. Oh, well.

[Eric P]

Gordon, sounds like a different problem than what I had. The pins on one of mine started to get real hot, it then began to melt the plastic around the pins. After this it was verry dificult to remove the bulb. FWIW my pc fixtures were made by JBJ and they warrantied one of my fixtures twice. Great customer support.

Eric...

[tdwyatt]

actually, thes are pretty much all the same problem to different degrees (NO PUN INTENDED). The issue usually involve a not-too-tight connection between the pins and the socket, or between the socket and the wiring for the power being supplied at the socket. In the presence of salt, or even high humidity, these endcaps may start to arc, and it is this heat that causes the problem, and is not limited to PC setups (any lighting that uses high voltage to start an ARC at/between the filliments or high voltage to make a plasma will do this.) The use of silicone grease to "water proof " the endcaps helps some, but the use of a non-conductive silicon at the end of the socket that is exposed to the atmosphere is of utmost importance to caulk for water vapor exclusion. What good does it do to make a water tight seal at the bulb/socket interface if you don't do the same for the back side of the socket?

A good dielectric grease for the socket itself will both prevent this issue and prevent the gaskets for the bulbs from sticking. There are bulb/socket greases made specifically for this use (and I use them on the mogul bases for MH as well)

In additiion to doing the waterproffing of the bulbs/sockets, I currently use ARC fault breakers and GFCI sockets for each aquarium to prevent this and other shorting issues that may result in home fires if left uncontrolled and unchecked.

hth.

[rtgordon]

Take a closer look at the pic. One of the the recepticles in the socket is burnt. I think that must have been where it arced. I will check with cust service tomorrow or monday. I will replace it for now, though. I need to route the wires better, though. I just put them up there with the intention of "cleaning up" around the tank at a later time. I guess I waited to long. Much of what you guys say makes sense... with the wires laying around, occasionally, the wire would catch when I remove the canopy on my own. one time, it caught and pulled the bulb out of the holder. I can see how this would loosen the connection and cause it to arc and heat up.

Now, any tool to reset the pin holders in the socket to insure tightness.
Do i put the dielectric grease on the pins when i insert them into the socket?

Thanks!
gordon

[Phishnoob]

I have a couple of these. I looked close and it looked like the pin fried a little melting the plastic. The cables are 15 bucks at Marine Depot or Premium Aquatics and you splice them in to the cable from the ballast. The only thing that can reduce this is to ensure the pins are engaged as much as possible in the sockets to avoid any arcing.

[rtgordon]

Originally Posted by Phishnoob

I have a couple of these. I looked close and it looked like the pin fried a little melting the plastic. The cables are 15 bucks at Marine Depot or Premium Aquatics and you splice them in to the cable from the ballast. The only thing that can reduce this is to ensure the pins are engaged as much as possible in the sockets to avoid any arcing.

So, get a new cable to be on the safe side? don't reuse the one that I have?

[rtgordon]

I put a sunpaq in place of the coralife and I must say... it's much more intense and makes the tank look much nicer and alot less yellow.

gordon