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 |   They may be small, but they're easy to work 
with   Our 2x3 LEDs are surprisingly easy to  work with. Having flat 
surfaces, they're simple to hold  for soldering, gluing, painting, etc. The 
gold plated solder pads make connecting wires a snap and the ceramic case is 
quite durable.   How's the LED going to be used?   The type of wire you connect depends on your application. If you 
plan to install them as smaller (and brighter) replacements for lights currently 
in your locomotives, and you expect the locomotive shells may be removed 
regularly for mechanism cleaning, etc., you may want to consider using a 
multi-stranded wire (about #30 or so) for flexibility in case you need to move 
things around a bit. If your application is as a light source in 
a structure, solid conductor wires like our N5030 #30 red, black, or white are 
	excellent choices. They're 
inexpensive at $3.95 and are on handy 50 ft. spools.  If your plan 
is to make flood lights or some type of lighting that will use tubing (like our 
.018" tubing) for conduit, you'll definitely want to use insulated magnet wire. 
Or, if in your plans you want to hide the wires totally from view (in cracks or 
grooves in structures), magnet wire's the choice. Four of our 
	N5038 #38 
insulated magnet wires will fit through a hole made with a #80 drill. This 
stuff's easy to hide. Whatever the choice, one rule to remember: 
Always pre-tin the wire and make sure that your solder has a flux core or 
that you're using a small amount of liquid flux. This ensures that the amount of 
time required for your soldering tip to be on the LED's solder pad to make a 
good joint is going to be the absolute minimum. The two easiest ways to kill an 
LED are: excess heat from soldering and excess voltage (or current). With good 
soldering  practices and protection from excessive current, these LEDs will 
easily last 50 times as long as an incandescent bulb, give off much more light 
and virtually no heat. What a deal!  
   Prerequisites: Regardless of the type of wire you're going to use there are 
several things that will aid in your success in working with these LEDs.  
    
Good optical magnification (Optivisor, etc.)
Bright lighting that's position adjustable.
Comfortable work area  so you 
can sit upright with your arms relaxed while soldering (helps prevent the shakes 
and fatigue).
Good magnification (really important)
	  A tool for holding small parts delicately but firmly. We 
	  recommend our NT301 LED/wire 
	  Holding Tool, it is designed specifically for this process and is not 
	  expensive
Small, low wattage (we recommend 
our 12 watt) soldering iron 
with needle tip or small chisel tip. Alternately, a temperature controlled 
soldering station (much more expensive but hard to beat).
Low-temperature wire solder with a rosin flux (not acid flux) core. Our 
N4200 (Kester, 
2% silver solder in the handy dispenser) is an excellent choice. Alternately, Kester 
63/37 or most  silver-bearing low temperature solders will work. 
To aid the speedy and smooth flow of solder and thereby minimize 
the heat the LED is subjected to, you will find that a small amount of liquid 
flux, applied with a tiny brush (or toothpick) applicator will be very helpful. 
Select a flux that is easy to clean. GC Electronics' #10-200 is an excellent 
choice.  Only a very tiny amount is required.
Simple test fixture (9 volt battery, an appropriate resistor, and 
clip leads) to test every wired LED prior to installation. All of 
our LEDs are pre-tested but you'll want to make sure you didn't zap one during 
soldering. It's better to know this prior to installation than after. Our N8021 
LED tester works great for this.
Good magnification (yes, we know...) Wiring LEDs We'll focus on wiring our LEDs using magnet wire. We feel that 
once you've got this technique down, it can be applied, in general, to the other 
types of wire we mentioned earlier. 
    
Pre-cut your wire 
longer than you think you'll be needing and tin/strip both ends of each 
wire. Even if you plan on putting this wire inside our .018" tubing and will 
probably have to snip off that tinned end. The reasoning here is that while 
you're setup to tin/strip, you'll probably be doing more than one wire and it's 
easy to do both ends at that time. This will facilitate easy testing of your 
wired LEDs. Test every one. The wire stripping & tinning procedure 
is covered in detail here. The wire can be found 
at the top of our web page titled Lighting Accessories.
	  
Our  LEDs are packaged 
in a black conductive plastic carrier strip. This strip contains pockets, or 
cavities that contain the individual LEDs and are held in place by a clear 
plastic cover-strip that can be pealed back to remove the LEDs. The reason that 
the carrier strip is conductive is that the LEDs are 
STATIC ELECTRICALLY SENSITIVE DEVICES. Therefore, before removal or 
handling of the LEDs, precautions to prevent static discharge should be taken 
(good grounding, anti-static mat or wrist strap, etc). Please review the 
	  packaging and handling procedure here.
Holding of the 2x3 
LEDs for soldering and holding the wires in accurate position is the essential 
part of the wiring process. After much experimenting, we have developed a tool (NT301) 
that does the job easily. It greatly simplifies the wiring process by holding 
both the LED and wire allowing you to have both hands free to 
make your solder connection. Shown below is a wired 2x3 LED with the anode (+) 
wire being held by the padded spring clip at the left. This tool works very well 
for all of our LEDs including our tiny Nanos. 
 
		
		Pick a pattern and stick with it. That is, get in the habit of 
soldering the cathode side first or the anode side first. We recommend using red 
wire for the anode (+) side. This follows normal electrical convention (the plus 
lead on your car battery or train power supply, for instance). The green wire 
for the cathode (-) side. If you're doing several, do all of one color first. We 
like to solder all of the cathode connections first because the LED face is 
marked with a small line denoting the cathode connection. Once this is done, 
there's no possibility for confusion (and shorting LEDs).
		To solder the first wire, lay it down on the solder pad so that 
the point where the tinned portion of the wire stops  and the insulation 
starts in lined-up with the back edge of the solder pad. Let the remainder of 
the tinned portion hang off the side of the solder pad. Or, you can pre-cut the 
wire so that the tinned portion is no wider than the solder pad. It's up to you. 
Follow the soldering procedure we covered in detail in the Using the 
		wire section 
of the Magnet Wire, making sure to minimize the time your iron spends on the 
solder pad of the LED. If you've left the tinned part long, snip it flush with 
the edge of the LED. Carefully slicing it off with a sharp scalpel also works 
well. Don't nick the gold pad.
		Gently  bend the wire slightly to the side so it's not 
hanging over the other solder pad. How you position the second wire depends on 
how you're going to use the LED. If you're making an HO ditch light for example, 
you'll want both wires exiting the LED from the same side. In this case, you'll 
want to trim the second wire so that the tinned portion is only the width of the 
solder pad and position it so that insulation starts as the wire exits the pad. 
If this LED will be mounted as a floodlight, you'll probably want the wires to 
exit up away from the LED back and be twisted together. In this case, turn the 
LED around and solder the second wire so that it exits the LED in the opposite 
direction from the first wire.
		If you've used additional flux, gently clean the back and sides 
of the LED.
		A graphic representation of the above procedure in 
		step-by-step format (wiring our Micro LEDs), including complete use of 
		our NT301 LED/wire Holding Tool, will be very helpful and can be reviewed by clicking
		here..    Testing your work Whether you're planning on wiring a bunch of LEDs 
or just one, we cannot overemphasize the importance of testing your work 
before placing wired LEDs in you structures or other projects.  Imagine building for 
example, a streetlight and discovering after the detailed assembly that somehow, 
the LED got fried or is shorted. At a minimum, strong words would likely 
ensue...  We use to recommend 
building a small portable tester and even included a circuit diagram and parts 
list on this page. Well, no more. We now carry an
Intelligent LED Tester that is very 
inexpensive and will automatically test any 20ma LED regardless of color 
or pin configuration. It has a built-in state-of-the-art current source to 
ensure each LED receives 20ma (± 1%) current. Simply snap it 
onto a standard 9-volt battery and you're ready to go.  
  It's extremely portable so 
it can be used to 
see how different lights look at various places on a layout, or in and around 
different structures. Happy testing and may all of your wired LEDs work the first time. Please 
let us know if you have any questions or problems.  © 2008 Ngineering |