Electrician Talk banner
1 - 20 of 20 Posts

·
Premium Member
Joined
·
19,752 Posts
Discussion Starter · #1 ·
I have a customer that complained about having a dim LED sign. And some of the reverse channel letters out.
I found a couple of bad drivers 120 volt / 12 vdc, 5 amp 60 watt, and changed them.
I rode the site last night and found the sign to be kinda dim with all of the letters now lit, some a little less than others.

There are a total of three sets of channel letters, on three sides of the building, each with two drivers per set of channel letters, all demonstrating the same low light output.
The building Is about 5 years old and this is something the out of town management noticed.

Any ideas or insights about LED channel letters or LEDs used like this?
 

·
Licensed Journeyman
Joined
·
5,880 Posts
jrannis said:
Every indication points to the LEDs in this sign are approaching the end of their useful life
I thought they lasted forever. Lol.
 

·
RIP 1959-2015
Joined
·
39,618 Posts
I have a customer that complained about having a dim LED sign. And some of the reverse channel letters out.
I found a couple of bad drivers 120 volt / 12 vdc, 5 amp 60 watt, and changed them.
I rode the site last night and found the sign to be kinda dim with all of the letters now lit, some a little less than others.

There are a total of three sets of channel letters, on three sides of the building, each with two drivers per set of channel letters, all demonstrating the same low light output.
The building Is about 5 years old and this is something the out of town management noticed.

Any ideas or insights about LED channel letters or LEDs used like this?
Can the leds in the sign be changed or even add more to them?
 

·
Premium Member
Joined
·
19,752 Posts
Discussion Starter · #6 ·
Can the leds in the sign be changed or even add more to them?
Good question.
I found out that this is not an unusual problem and that after 10,000 hours, they should be changed.
Of course, the latest and greatest LEDs are much better than the 2006 technology, they say.
The replacements are peel and stick and should be just fine. They have about 60-20" letters so $100 -$125 per letter should make it a nice job including the boom lift and new drivers if necessary.

The material the letters are made from will not support the weight of or UL approved for neon.
 

·
Premium Member
Joined
·
19,752 Posts
Discussion Starter · #7 ·
if they are all dim i wonder if the incoming voltage is low. have you checked it at the source
The signs are on three separate para-pits and are fed from different sources. At first I thought maybe the drivers were overloaded until I found out the age of the installation.
 

·
Registered
Joined
·
6 Posts
Not sure if this will help but, I do some work on Able and Millwakee price signs for gas stations. I have a lot of calls for dim lit single lines, multiple lines and all lines. For example the single line would be: UNL $ 3.99 and multiple lines would be: UNL $ 3.99, PREM $ 4.99 ....
In my case my signs have a remote key pad to change prices and program the signs. In the program menu each line or all lines brightness can be adjusted. Some are wired and some wireless but they are all controlled by cheap or sensitive circuit boards. So voltage spikes and power loss can wipe out the programs easily. Im in Kansas City and I run most of these calls the day after thunder and lightning storms.
Not sure how your sign works but you may check the program settings if you have that option.
 

·
Premium Member
Joined
·
19,752 Posts
Discussion Starter · #12 ·
The units are controlled by a photo cell.
The more I read about LEDs the more the information points to LEDs not going dim but simply "burning out" .
With that said, some servicing would be in order. Exactly what type of servicing is the real question.
My conclusion is that the sign, reverse channel letters, are for one thing, due for a professional cleaning. These signs typically have an clear acrylic back that faces the building. I suspect a few years of soot and dirt could be attracted to he plastic so, we would need to clean and inspect the signs and replace any dead modules.

One week snorkel lift rental
Up to 150 modules
Cleaning supplies
Consumables

30 hours

$4800.00 would be the very low end
$ 6200 best case
 

·
Registered
Joined
·
6 Posts
Dim leds

I guess i did leave out that important part! I think that you and I may have two totally different applications, however, Many of my repairs are as simple as cables pulled from a harness (birds get in and nest), corrosion is a big one! I never take the bucket up without: corrosion cleaner, toothbrush( or some kind of brush),and electronics grease. My boards have photo eyes, and the same coating your talking about. The photo eye comes from the factory w green vinyl tape over it? Im not sure why but they tell me not to remove it, and adjust light from key pad.
My biggest issue is these parts are not desinged to be in the elements. So when the sign co. shoots 100 self-tappers through the structure it leaks like hell all over the boards. That and pigions nesting in them makes for a ton of corrosion on the cable connections.
I guess what I would try is: cover the photo eye( not too dark). Then clean and re-seat all the cables.

One more thing because you mentioned the chanels. 1 bad channel can drag down all the others or just a couple. Isolate the chanels one at a time to find the bad one. The try to isolate the device (power supply, driver board, cable, LED card) in that channel that is causing problems.
I can remove a bad chanel from the whole unit and everything else will come up-OK.
Ive started installing a switch or some type of disconnect in the sign because you have to cycle power all the time! I sucks going up and down in the bucket to flip a breaker. Hope some of this will give you some ideas! Good luck
 

·
Premium Member
Joined
·
19,752 Posts
Discussion Starter · #14 ·
Thanks for the update.
This system has two drivers for the sign.
Each driver powers about 13 pieces of the total of 26 letters and logos

The sign is uniformly lit and uniformly dim.

It wouldn't be very practical to test each one and try to observe which one could be bad.
I proposed cleaning the signs and put in an allowance for changing %25 of the LED modules and %25 of the acrylic backs.

They are now asking for us to replace %100 of the LED modules.
 

·
Registered
Joined
·
56 Posts
Thanks for the update.
This system has two drivers for the sign.
Each driver powers about 13 pieces of the total of 26 letters and logos

The sign is uniformly lit and uniformly dim.

It wouldn't be very practical to test each one and try to observe which one could be bad.
I proposed cleaning the signs and put in an allowance for changing %25 of the LED modules and %25 of the acrylic backs.

They are now asking for us to replace %100 of the LED modules.

A few questions for ya...

How far are the drivers from the first LED module.?
What gauge wire was used for the secondary run?
Are the letters each fed by their own secondary wire from the driver?
Or are they powered in series?
What is the brand of LED and DRIVER?
What color are the LEDS?
Did you verify adequate primary voltage?
Is their a chance due to the placement, the drivers are over heating?
Ambient temp around the driver exceeding 120F?
What is the wattage per foot or wattage per module on the LED product?

Are the LEDS facing the back of the face?
If so, is the inside of the face painted white?
Or are the LEDS attached to the face, and facing the acrylic?
What is the spacing from the back of the letter to the wall?

Pictures of the modules would be helpful.
 

·
Premium Member
Joined
·
19,752 Posts
Discussion Starter · #16 ·
A few questions for ya...

How far are the drivers from the first LED module.? Just a few feet
What gauge wire was used for the secondary run? It looked small, maybe 16s
Are the letters each fed by their own secondary wire from the driver?Each letter in in parallel connected in a junction box with a blue wire nut
Or are they powered in series?
What is the brand of LED and DRIVER? Brand of LED is unknown, Drivers were one brand, half of each sign was changed to another brand of driver with no apparent difference in brightness
What color are the LEDS? They are thought to be Blue as the light coming out of the back is Blue
Did you verify adequate primary voltage? Three signs fed from two seperate electric rooms with separate utility vault. The letters are about 8 years old and just recently been "flagged" as dim. Most likely they have been dim for a while buy just now noticed due to the recent time change
Is their a chance due to the placement, the drivers are over heating?
Ambient temp around the driver exceeding 120F?
What is the wattage per foot or wattage per module on the LED product?
Unknown but nothing has changed environmentally
Are the LEDS facing the back of the face? Assuming yes they are reverse channel letters
If so, is the inside of the face painted white? Unknown but were acceptable at the time of installation
Or are the LEDS attached to the face, and facing the acrylic? Unknown
What is the spacing from the back of the letter to the wall? Unknown

Pictures of the modules would be helpful.
Not really possible unless the costumer commits to hiring us to investigate

Good points. Thanks for the interest
 

·
Premium Member
Joined
·
19,752 Posts
Discussion Starter · #17 ·
Good points. Thanks for the interest
Guys,
Just needed to bump this in case someone has any more info.
I spoke to the manufacturer and they insist that the LED modules would be expected to be dim after 8 years of use, every night, seven days a week.
Close to 30,000 hours of operation.
 

·
Never Used Scotchkote
Joined
·
2,811 Posts
jrannis said:
Guys,
Just needed to bump this in case someone has any more info.
I spoke to the manufacturer and they insist that the LED modules would be expected to be dim after 8 years of use, every night, seven days a week.
Close to 30,000 hours of operation.
That looks like the answer then. Start the bid for a whole new retrofit. If you can get the same brand then you could re use the drivers. And maybe bring up a tube of silicone to cover any holes that may be leaking onto your LEDs
 

·
RIP 1959-2015
Joined
·
39,618 Posts
Guys,
Just needed to bump this in case someone has any more info.
I spoke to the manufacturer and they insist that the LED modules would be expected to be dim after 8 years of use, every night, seven days a week.
Close to 30,000 hours of operation.
I wonder how true that will be..
 
1 - 20 of 20 Posts
Top