Is that possible?
I was downstairs operating my layout this morning, and I noticed that one of my searchlights operated correctly with the green portion of the bi-polar LED, but when I flipped the toggle, the red portion of the bi-polar LED did not light up. I thought that it would be all or nothing on a bi-polar LED.
Or, has the red wire connection to the LED somehow come loose?
Rich
Alton Junction
Since a bipolar LED is really two in one package, it would be possible to have one device die. Or, as you say, a wire may have come loose too.
Rich,
With the power off, check to see if you have continuity to the side that won't light,both legs.
If not you have a loose,or no connection'
Cheers,
Frank
zstripe Rich, With the power off, check to see if you have continuity to the side that won't light,both legs. If not you have a loose,or no connection' Cheers, Frank
Frank,
I wish I could do that, but the legs of the LED are buried inside the signal light shield and mast.
Once before, I had this happen to me, and I wound up sending the signal back to Tomar Industries for repair.
These little guys are too expensive to mess with, at least with the tools that I have at hand.
Sorry about that,,, I forgot that they were a signal head.. I still believe though, it is probably a loose wire and or cold solder joint, I don't ever recall a led going bad.. Do they let you know what the problem was when they repair it??
zstripe Rich, Sorry about that,,, I forgot that they were a signal head.. I still believe though, it is probably a loose wire and or cold solder joint, I don't ever recall a led going bad.. Do they let you know what the problem was when they repair it?? Frank
They do. Duane and Marie own the place and their customer service is great.
The LED in this instance is resistored and heat shrink tubing protected, so I suspect that the wire inside the mast or at the signal head is loose or broken. The wire is not much thicker than a human hair, or so it seems.
I can attest to the size of the wires,, I have 6, 2 light VERTICAL signals,not Bipolar from Tomar,4 installed and 2 in the wings,waiting. I think going on 15yrs now,no problem at all with them..
Cheers,,,,,ROAR!!!!
I should own stock in Tomar Industries.
I have tons on their dwarfs, single search lights and double search lights.
It is always a joy trimming those tiny wires to get them ready for soldering onto a resistor.
I just replaced a bipolar LED on one of my turnout indictors, the Red was burned out. I removed it and tested it on the bench; no red. It can happen!
-Bob
Life is what happens while you are making other plans!
Bob, what caused it, any idea?
If it is a bi-polar LED then there are only two wires and they operate both the red and the green LED. It wouldn't make since for a loose wire to cause one color to fail and not the other. Are these three legged LEDs? If so, then they are bi-COLOR, but not bi-POLAR( I do see a lot of people refer to three-legged LEDs as bi-polar, but that is incorrect). If that is the case, then a loose wire could make one color fail and not the other.
CSX Robert If it is a bi-polar LED then there are only two wires and they operate both the red and the green LED. It wouldn't make since for a loose wire to cause one color to fail and not the other. Are these three legged LEDs? If so, then they are bi-COLOR, but not bi-POLAR( I do see a lot of people refer to three-legged LEDs as bi-polar, but that is incorrect). If that is the case, then a loose wire could make one color fail and not the other.
I actually don't know if the LEDs are 2-leg or 3-leg. I cannot see the legs because they are contained inside the signal mount. There are 3 wires, a green, a red, a white, so maybe 3-leg?
Not that this makes it correct terminology but Miniatronics, for example, refers to both their 2-leg LEDs and their 3-leg LEDs as bi-polar.
I will ask Tomar Industries when I call them on Monday.
I have the same three wires on my Tomar 2-lite vertical signal,and I know for a fact they are not bipolar..
If there is only one head, and there are 3 wires, then it's definitely not a 2-lead LED. One wire plus the common will be red, the other wire plus common will be green. There are either two LEDs, or a 3-lead bi-color LED.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
rrinker If there is only one head, and there are 3 wires, then it's definitely not a 2-lead LED. One wire plus the common will be red, the other wire plus common will be green. There are either two LEDs, or a 3-lead bi-color LED.
So, what's the difference between a bi-polar LED and a bi-color LED?
A bi-color LED has two different color LEDs in the same package. Most bi-color LEDs have either three legs our two legs. If it has three legs, then one leg is common and each of the other legs goes to one of the LEDs. To light one LED, you apply power to the common and one of the other leads. To light the other LED you apply power to common and the third lead. To light both LEDs, you apply power to the common and both other leads. If the LED only has two legs, then it is bi-polar. A bi-polar LED has the two LEDs wired in reverse-parallel - the anode of one is wired to the cathode of the other and vice-versa. You apply DC power with positive on one leg to light one LED. You reverse the polarity of the power to light the other LED(hence the "bi-polar" monicker), and you apply AC power to light both LEDs.
Thanks, CSX, that is very helpful.
Mine are two leg bi-polar and I don't know what caused it. I was replacing the turnout and disconnected the wires from the Tortise. When I replaced the wires only one color worked and nothing had changed as I use the push-on connectors, so I didn't have to unsolder anything.
It's like Déjà vu all over again! This very same thing happened to me tonight and, of course, I had a few friends over for a little operating session. I went to throw a switch (Tortoise) that happens to have A: a bipolar on the dispatcher's panel and B: one each of red and green ordianry LED in a trackside signal.
Panel LED lights red but when I toggle to green it goes dark and the Tortoise doesn't see current to throw. I have maybe 60 or 70 LEDs used this way, almost all of them 5mm milk white bi-polar and this is the second time in ten years I've had to replace one. So far I haven't had any go bad in a signal application.
Keep in mind, too, that most of what us hobbyists see are seconds or surplus stock so there's a good chance that some of the components we get are not up to Mil Spec. standards.
Take care, Ed
richhotrain CSX Robert If it is a bi-polar LED then there are only two wires and they operate both the red and the green LED. It wouldn't make since for a loose wire to cause one color to fail and not the other. Are these three legged LEDs? If so, then they are bi-COLOR, but not bi-POLAR( I do see a lot of people refer to three-legged LEDs as bi-polar, but that is incorrect). If that is the case, then a loose wire could make one color fail and not the other. I actually don't know if the LEDs are 2-leg or 3-leg. I cannot see the legs because they are contained inside the signal mount. There are 3 wires, a green, a red, a white, so maybe 3-leg? Not that this makes it correct terminology but Miniatronics, for example, refers to both their 2-leg LEDs and their 3-leg LEDs as bi-polar. I will ask Tomar Industries when I call them on Monday. Rich
I sent the signal back to Tomar Industries for repair.
I spoke to Duane at Tomar Industries, and he indicated that the search light signal is a 3-leg bi-color LED.