Hi all, I was wondering if someone might know how to wire these 4 pin led on/off pushbuttons? No instructions came with them and I can't figure it out. As most of you know I am dumb as a box of rocks when it comes to this stuff!
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Now that we know the switches have designations stamped on them, please ignore my previous advise.
Hi Arther, here is the best information I can give you from my ohm meter, in the photo below the 2 larger post on the to are connected when the button is pushed in, but none of the others are. I cant seem to get power threw the switch. I put 12volts to the big post, but nothing comes out on the other post.
I hope this helps.
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What is the embossed writing on the bottom of the switch next to the leads. Can you take a close up of that?
You beat me to it, Chuck. I think I see a + and - on the small posts, could be for the led.
I think that's it. The fat posts get shorted together and the thin ones are the light. Not sure what voltage lights the light though...should need a resistor. Maybe look at the same switch by different vendors to get some info.
The top two terminals marked with the +/- are obviously the light, looks like it has an LED since it has polarity. The bottom two terminals are the contacts, they are independent of any connection to the light.
I have the same switches, I can assure you that the larger terminals are the power contacts. 
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@gunrunnerjohn posted:The top two terminals marked with the +/- are obviously the light, looks like it has an LED since it has polarity. The bottom two terminals are the contacts, they are independent of any connection to the light.
Thanks John, I tried wiring hot to the plus side and ground to the negative side and nothing happened, the led light didn't even come on.
The contacts and the light are separate. The light is just an LED, so if you hooked up power without a current limited resistor, it's no longer an illuminated switch! That would have smoked the LED for sure! You need to provide a 1K resistor and diode in series with the internal light. If you want it to indicate switch operation, then you need to provide the LED a ground and the + side goes through the diode and switch to the switched power.
@gunrunnerjohn posted:The top two terminals marked with the +/- are obviously the light, looks like it has an LED since it has polarity. The bottom two terminals are the contacts, they are independent of any connection to the light.
I have the same switches, I can assure you that the larger terminals are the power contacts.
Ok so If I understand correctly I might have polarity backwords.
Next question, the bigger post is just for hot in and hot out to center rail?
Hi Steve, any diagram would be great! fYI I'm using a Z4000 if. It matters.
Mike, here's a diagram showing the connections to the 4 pins.
The two small open circles represent the two larger switch terminals.
The + and - in the diagram are the smaller two LED terminals on the 4 pin switch.
In the physical world, the diode will have a stripe or band around one end and should be connected in the orientation shown in this diagram. The resistor has no polarity and can be connected in either orientation.
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Thanks Steve ow I will have to order some diodes. And wait for them to arrive. Thank you again!
LOL Please don't laugh at me, but I was just looking at Resistors on the Bay and to be honest I dont have a clue on what one to buy and if I should more then I need right now for future projects!
You all rock, can you please help with this?
Mike, how many switches are you wiring? I can send you a few to get you started.
Hi John, I only have 10 to wire.
I have all the resistors and diodes you'll need, shoot me an email with an address and I'll send them out to you.
As a practical matter, have you guys settled on a method of shipping a few lightweight penny diodes and resistors without incurring the $5 or so minimum USPS package charge? I was thinking a piece of cardboard with cut outs keeping everything under 1/4" limit for envelopes and adding the small non-machinable surcharge because of the stiffness? No tracking but should get postage less than $1.
Hi John, I PM'ed you my address, as I stated in Steve's diagram I don't see where a diode goes.
@stan2004 posted:As a practical matter, have you guys settled on a method of shipping a few lightweight penny diodes and resistors without incurring the $5 or so minimum USPS package charge? I was thinking a piece of cardboard with cut outs keeping everything under 1/4" limit for envelopes and adding the small non-machinable surcharge because of the stiffness? No tracking but should get postage less than $1.
Stan, I ship a lot of tiny stuff in a First Class envelope, I just use a cardboard cutout and tape the stuff into the cardboard opening. When I'm giving stuff away, I don't like it to cost me any more than necessary! 
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@stan2004 posted:As a practical matter, have you guys settled on a method of shipping a few lightweight penny diodes and resistors without incurring the $5 or so minimum USPS package charge? I was thinking a piece of cardboard with cut outs keeping everything under 1/4" limit for envelopes and adding the small non-machinable surcharge because of the stiffness? No tracking but should get postage less than $1.
I tried that with some RF signal diodes and they were crushed by some roller at the post office. All the guy got was four leads and some glass dust.
When you think about it, 5$ is an incredible bargain for someone to carry a package across the country and deliver it to a front door.
Wondering if all leds could be fed with one resistor and diode to a pair of terminal strips, or does that get into the iffy part of paralleling leds
You could use individual resistors and one diode.
Mike's resistors/diodes are in the can.
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Thank you so much John I also got your watchdog generator hooked up, but havent powered it up yet. I came in to make sure is just 2 wires to the output of the TIU channel for my sidings. I don't want to burn anything up! LOL
@mike g. posted:Thank you so much John I also got your watchdog generator hooked up, but havent powered it up yet. I came in to make sure is just 2 wires to the output of the TIU channel for my sidings. I don't want to burn anything up! LOL
That's all that's required, just connect the two wires from the terminal block to the TIU output, or anywhere on the track.
Sounds great John! Thank you again. photo of it below installed.
Also whileI have your attention, I wanted to get your input on the photo below. I have a 2 stall engine house, if it were you would you just power the siding with the push button? Or power both engine house tracks?
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@mike g. posted:Also while I have your attention, I wanted to get your input on the photo below. I have a 2 stall engine house, if it were you would you just power the siding with the push button? Or power both engine house tracks?
Clearly, I would want each stall to have independent power and then another switch for the siding. That's the way I did my freight yard, there are a couple switches for the entrance siding and each actual yard track has it's own power switch.
@mike g. posted:Sounds great John! Thank you again. photo of it below installed.
Also whileI have your attention, I wanted to get your input on the photo below. I have a 2 stall engine house, if it were you would you just power the siding with the push button? Or power both engine house tracks?
I'm with John on this one Mike. Three separate power blocks.
Bob
Thank you, John! That's what I was thinking and why I bought so many switches. Just wanted to run it by someone who has vast experience in model train building!
@John H posted:Wondering if all leds could be fed with one resistor and diode to a pair of terminal strips, or does that get into the iffy part of paralleling leds
It "could be" done this way but the individual LED brightness would dim as you turn on more switches. Since resistors are just a few pennies each (or free if you can cajole GRJ into sending you some)...
@cjack posted:You could use individual resistors and one diode.
I like this alternative. Actually the individual LEDs will dim a bit as you turn on additional switches but the change will be so small as to be un-noticeable.
Here's one implementation of this approach showing just 3 switches but hopefully it shows the roadmap to get to 10 switches.
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Wouldn't a better use of the non-lighting diode be to protect the LED in reverse bias? So, the diode across the light terminals, in reverse, and then all that in series with the resistor? I mean, if the LED is working, in forward bias, it will be between 2.5 and 3.something depending on the color. The reverse voltage will depend upon the reverse leakage characteristics of both LEDs and would probably have to be solved with some SPICE simulator, or just fire it up and see what happens on a guinea pig.
I have at several locations LEDs back to back, and then a 1k resistor, soldered directly to the underside of the track. Some of them are these ancient rectangular LEDs from the 1980s but hey the still work (soldered them maybe in 2005). When you do a conventional whistle on a transformer, one LED gets brighter than the other, as it should.
@stan2004 posted:It "could be" done this way but the individual LED brightness would dim as you turn on more switches. Since resistors are just a few pennies each (or free if you can cajole GRJ into sending you some)...
They're in the mailbox and should be on their way today. I tossed a few extras, just in case.
@illinoiscentral posted:Wouldn't a better use of the non-lighting diode be to protect the LED in reverse bias? So, the diode across the light terminals, in reverse, and then all that in series with the resistor?
The LED and diode in series only puts half the power through the resistor. The series diode IS protecting the LED from reverse voltage.
Morning guys, just wondering if you all think Stan's method would work? Sure, looks easy.
@mike g. posted:Morning guys, just wondering if you all think Stan's method would work? Sure, looks easy.
It looks good to me.
Looks fine, truthfully I did my ten switches on my yard with one diode. 
