LED corncobs

[kcollinsdesign]

We have been having problems with LED corncobs failing. These are usually for large cabinet signs that were designed for HID lamps. These lamps are installed correctly, with adequate ventilation, exceeding manufacturer's recommendation for the amount of air (envelope) around each lamp. Sometimes they just need to be tightened (again they were installed correctly - the design of the base is different, of course, from the original HIDs with a hard metal contactor at the base of the lamp instead of the soft metal on HID lamps, but usually they just stop working. All wiring is to spec, power supplies working properly, and voltage at the socket is well within spec.

This is more of a nuisance with signs that have easy access (the manufacturer usually provides a five year warranty), but beomes a major expense when the sign is 75' - 130' in the air (highway signs), that you have to jump into and often rent equipment to reach.

Does anyone have any recommendation for reliable LED corncobs that can be screwed securely into sockets and will last at least five years? The current job has failed corncobs (400w HID replacements) and the owner is sick of paying several thousand dollars each time they need to replace faulty lamps. He replaced lamps (once again) just a few months ago, and they are already starting to fail. The client wants a five year parts and labor warranty, and is willing to pay for premium lamps and whatever it takes to stop bleeding money.

Like I said, this is not a one-off problem. I have been seeing this since the corncobs came out.

 

[weyandsign]

"Feit Electric" corncobs seem reliable.

 

[kcollinsdesign]

Used MaxBrite one's in the past, but they too fail in a couple of years, not nearly 5 as the warranty states, then the warranties are pretty useless because as you said, you need a 3 grand lift to get to it so who cares about the $100 you saved returning one lamp under warranty.
The best looking one's I've put in were from France, the maker's of the original Franceformer. They had fans, directed airflow, and little chains to secure the lamp to the frame in the event that the socket broke (because the lamp weighs 10lbs for a 400w equivalent).

Hey, thanks! I'm looking into those France corncobs. They also offer a 5 yr part/ 1 yr labor warranty (with caveats, etc., of course). Anyhow, seems like they may have figured a few things out (they have been making sign lighting products forever).

 

[Notarealsignguy]

Can you go back to the HID? IMO, all of these LEDs are junk, even the good ones. My electrician friend said he sees them fail all of the time, warranty covers the light but customer has to pay the labor. Pretty worthless when you could get a solid 5+ years out of cheap fluorescents.

 

[Notarealsignguy]

Ya can, but then you need to install the ballast and cap, that takes a decent chunk of time depending on conditions inside the cabinet, and since it's been gutted and wired around to get the sockets 120v a/c, it's tough. Additionally the components are always going up in price, to the point that cutting 4 wires, splicing them together, and slapping in a corn cob is cheaper than troubleshooting lamp vs ballast vs cap, and carrying all 3 on the truck, especially if the service switch is on the ground and you don't have a helper sitting on the ground playing minesweeper with friends or whatever. Plus there isn't even the illusion of a warranty on the lamps and the power consumption will quadruple. Yet in the end, if it burns for longer you might as well go back to glass and all around save money, I just wish there wasn't that explosion 5 years ago of service trucks swapping out to garbage modules that left cabinets in a absolute mess. Ever see what happens when some dummy tapes modules to existing lamps, then the lamp gets broken? It's like a frickin cat o nine tails!

Not sure on HID but the energy consumption on LED vs fluoro isn't really substantial if at all. It's all overrated. Ballasts have went up but really, if you're on a service call you just change them all. For tubes, it's almost faster to change bulbs/ballasts than it is to to convert to LED.
Honest question here, couldn't you just throw some cheap 8' T8 fixtures in there and be done with it?

 

[kcollinsdesign]

The lattice modules work well and tend to not fail as regularly as the corncobs. For the problem I have now, I would need to place two arrays of SF modules in order to get the correct distance from the face. That leaves no space for a guy to climb around inside the sign (lots of fun, I tell you), so the sign would need to come down, at least one flex face removed, and essentially be re-built. Then if any of the modules or wiring failed, the sign would need to be taken down again, face removed again, etc.

HID lamps needed to be changed out every two years or so. LED corncobs last longer on paper, but they go bad and need to be changed all the same. I guess, considering the power savings, they may be coming out a little ahead if the corncobs last a couple years.

The customer wants a 5 year parts and labor warranty. Well, I can handle that on the parts end, but no way labor. Best I can do is find the best corncobs I can and charge them each time we go up there. Hopefully, for the customer, that is only once every two years or so (same as with the old HID lamps, only the corncobs cost 6x as much to replace)!

 

[kcollinsdesign]

I'd say they won't take up that much room, you'll be left with the same squeeze around the central frame, but it would be a nightmare to get tangled up in with nothing but a flex face holding your weight, been there, I'm good.
We often pull a side and bottom loose on such a sign to work up under the face, doesn't work so good if you have a hanging basket though. Depending on the clips used, this is either easy, kinda easy, or impossible if they doubled the face around some flat stock and screwed it down, then added filler. What kind of clips are ya working with on this thing?

I dunno. Likely a SignComp type system (that's what I usually find). I would need to go up there to see, which (for us) would require a $1500 equipment rental. I am trying to get info on the OEM; if I can figure out who made it I might be able to get info on the tensioning system, along with the exact size and the number and size of the original HID lamps. It's a Shell sign, so probably Federal Heath. I would need to go through the Shell branding program, and of course they will want to send their own vetted (and union) contractors to do the job. The last company who worked on this sign are not returning calls to the sign owner, and are reluctant to share any informaion with a competitor (they would prefer we figure it out ourselves).