Toggle switch/LED wiring help.

[CR6707]

Hey everyone! 

I want to wire up some toggle switches for blocks on my layout and want to use LED's with the switches.  when you flip the toggle switch up or down i want to have indicator lights to show which power pack has control of that block.  Either i am not searching correctly, or dont understand what i am reading.  I am not electrician by any means so some of the advanced schematics might as well be in greek!  It cannot be that hard seeing everyone uses them.  If i need resistors as well, what do i need??  Thanks in advance for the help!

[engineshop]

With such a toggle switch, you can easily wire it. I found this toggle switch with 3 sets of pins but in your case, a toggle switch with only 2 sets is enough.

http://www.micromark.com/toggle-switch-3-pole-double-throw,8424.html

You would use one sets to wire the block with the power packs, another set you hook up the LEDs with a 2,3 volt source.

You could use a just a single toggle switch but you will have a more complicated wiring (with resistors) if you use the adjustable power from the power pack to light up your LEDs.

[DKS]

You could use a just a single toggle switch but you will have a more complicated wiring (with resistors) if you use the adjustable power from the power pack to light up your LEDs.

Using the power from a "power pack" for LEDs is not recommended. See this thread for more details: https://www.therailwire.net/forum/index.php?topic=27923.30

You really should use a separate regulated power supply (or even just batteries) for the LEDs. You'd only need one resistor per switch, since only one LED will be lit at a time for each block. Give me a bit to post a schematic, unless someone else can jump in here who has a few more spare cycles.

[nkalanaga]

Unless you're using common rail wiring, you really should have a 3-pole double throw switch.  Having both rails blocked and controlled makes power pack wiring much easier.

[peteski]

I'm also unclear how exactly this setup is supposed to look like.  Is there one switch per block?  Are there only 2 throttles?   If that is the case then yes, a 3PDT switch would be the best to use (2 poles for the track power wiring and the single pole for the LED).  If center-off switch was used it could be isolated with the switch in the center-off position (to park the locomotive).

No, I'm not going even going to mention DCC. 

[CR6707]

What i know so far is that you only need one side of the 3 pole switch to wire your cabs and blocks.  can you use the other side for your LEDs?  wire dc on one side of the switch and ac w/ resistor on the other side?

[DKS]

What i know so far is that you only need one side of the 3 pole switch to wire your cabs and blocks.  can you use the other side for your LEDs?  wire dc on one side of the switch and ac w/ resistor on the other side?

DC on one side, AC on the other? Not quite.

Here is one of many ways you can accomplish what you want. It assumes you are not using common rail wiring (that's where you connect one terminal of all throttles together on one ungapped rail). Thus you need a 3PDT center-off toggle switch; the one linked to above is not suitable, as it's not center-off (you should always use center-off switches so you can kill track power). Two of the three poles control which throttle is connected to the rails of the block, and one pole is used to control the LEDs.

Note that the LEDs are powered separately by either a battery pack (AAs would last a long time) or a regulated DC supply. Positive side of the LED supply is connected to the anodes (usually the long leads) of the LEDs.



Note that if you use two different color LEDs, you might need to use two resistors, one for each, that are different values to keep the brightness the same, although it's possible to find one value that strikes a good balance. You can also find pre-wired LEDs on eBay that you can connect directly, with no external resistor.

Here's a source for economical ($1.55 vs. $4.75) 3PDT center-off toggles: http://led-switch.com/Miniature%20Toggle%20Switch.htm
Scroll down to Model M303.

[CR6707]

So i went out to Radio Shack and got some 120vac lamps which have 2 wires coming from them.  None of them light.  What am i doing wrong?  I touched them for a brief second direct to fixed dc and direct to the ac.  nothing from either.  the packaging says they can be used for model railroading.  No install instructions on the package.  I never knew wiring lights on the control board was going to be this difficult!  Please help!!

[DKS]

So i went out to Radio Shack and got some 120vac lamps which have 2 wires coming from them.  None of them light.  What am i doing wrong?  I touched them for a brief second direct to fixed dc and direct to the ac.  nothing from either.  the packaging says they can be used for model railroading.  No install instructions on the package.  I never knew wiring lights on the control board was going to be this difficult!  Please help!!

120VAC? That would operate directly from the power coming from your wall outlet.
It is not recommended to use 120VAC on a layout control panel. It would be dangerous, and there is no need to do so.

If the diagram I presented in the prior post makes no sense, you may want to find a friend who understands basic electronics to help you out; otherwise, you run the risk of damaging models or creating hazards for yourself.

Or, you can take a break from modeling and bone up on basic electronics.

For starters, here are some terms you will need to understand. (I'm leaving out "current" for the sake of brevity.)

V = voltage
AC = alternating current; polarity ("positive" and "negative") switches back and forth at a fast rate.
DC = direct current; polarity remains the same (positive is always positive, negative is always negative).

AC would be present at your wall outlet. The rate of alternation is 60 times a second.
DC is what you will get from a battery, which has positive and negative terminals.

The reason your Radio Shack light did not work is that they needed 120 volts. Your power pack only delivers one-tenth of what it needed.
Voltage ratings are critical: your power supply must always match the voltage requirements of the device being powered.

Your wall outlet delivers 120 volts, which is a dangerous level (if you touched the wires with your fingers, you'd receive a nasty shock).
A typical battery delivers 1.5 volts, perfectly safe to touch the terminals.
A typical power pack delivers around 12-16 volts, also a safe level. Conventional (non-DCC) model locomotives run on around 12 volts DC.

The subject is much deeper, and beyond the scope of a message board thread, but this will help you identify some of the terms used in modeling.

[GaryHinshaw]

Please heed the good advice from David.  You might want to pick up a basic reference book about wiring, for example, this one from Kalmbach:

http://www.kalmbachstore.com/12403.html

-gfh

[robert3985]

Great drawing DKS.  Talk about quick service!

Excellent advice Gary.

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