Thanks to all that helped here! - relay wiring.

I would think 7+8 are coil/power in.

5+6 power in.  1-4 = NO- Normally open and NC- Normally closed.  

A picture from the side(s) would be more useful. But 7-8 coil, 5-6 poles, 1-2 and 3-4 are the throws. You can look inside and see which are NO (Normally Open) and NC.

Since the armature has to go toward the coil when the relay picks, I would venture a guess that 3-4 are the NO contacts and 1-2 are the NC contacts.  In the side picture, you can see the arm resting on contacts 1-2, and I'm guessing the relay isn't powered in the picture.

Very good observation!

Take a close look at PICT004.  The wire comes down off terminal 6 so that is the throw.  The stationaries are 2 and 4.  That changes things to 6-2 as NC and 6-4 as NO.  For the other side 5-1 is NC and 5-3 is NO. 

To answers the OP question, 7-8 are the coil terminals and  it does not matter which is neutral or power since it is AC. 

Based on the schematic above, the hot should connect to terminal 5, the red light should be connected to terminal 3 and the green light to terminal 1.   Likewise it can be hot to 6, red to 4 and green to 2.     

walt rapp posted:

I started a thread (https://ogrforum.com/...-accuator-for-signal) about using an accuator to control a track-side light (sorry I don't know the correct term).  It evolved into using a relay instead.

I have an AC DPDT relay that I only used once about 15 years ago.  I lost the directions for what each post does, that is, how to wire it. 

Are you sure it's an AC relay?  The part number on the top will identify what you have and then the datasheet will have the assignment of pin number to function.  Based on the lettering I can see from your first photo, I'd guess you have an OMRON LY2 12V DC relay.

It's already been explained (like what GRJ was saying above), but here's a link to a picture in another thread that might help a little. Works for most 'ice cube' relays. This was explained to me many years ago by an 'old-timer'. Way back before I was an 'old timer' myself. 

If you are sure it is a AC relay, I would say #7 goes to the 12v positive post of your AC transformer for your Accessorary connection and #8 would go to your trigger rail for the signal.  #6 would be the plus input from Acc. tap,   will say for now that is the normally open tap. #$ & #2 would be to the red and green post of signal,   If reversed lights on then reverse signals.

Marty

If it's a DC relay, adding a diode and capacitor will solve the AC/DC issue.

Stan has great eyesight! I missed that earlier...

Here is a shot of a relay sock it I use:  OOPS when I click on the browse feature, it doesn't work...

Marty

here are some better pictures to back up stan2004's point...

here is a link to an OMRON data sheets for the LY family offered now.  the physical case looks different, but i have to imagine the functionality would be the same...

http://www.ia.omron.com/produc.../itemlist/index.html

the coil is plainly marked 12 VDC.
good luck with it....gary

ah... what an abysmal site... here is the LY data sheet.... pinouts near the bottom.

http://www.ia.omron.com/data_p...4_8_csm54.pdf?id=949

Here are two links:  #1 is for relays,  https://www.galco.com/buy/NTE-...tronics/R14-11D10-12     #2 is the sockets:  https://www.newark.com/nte-ele...ay-socket/dp/10M0358    

Marty

Here are a couple of Pics showing  relay  Wire color is signal wire:

hello

I don't know if you can read this but I will try 

kevin

Walt,  It might help you understand how to hook these up, if you have a better understand how a DPDT relay works.    So here goes my attempt:     Terminals 7 & 8 are the leads to a solenoid (electro magnetic coil),   When the coil is energized the normally open (NO) contact gets closed, and the normally closed (NC) contact opens.    

Based on your picture above  terminals 7 & 8 are for energizing the coil.   They are not polarized so one gets 12 Volts DC + and the other needs to be tied to the insulated rail on your track. 

Terminals 5 and 6 are the power source voltage for your accessory light,  could be AC or DC. If it's a typical 3 rail accessory like a green/red block signal then whatever the signal instructions call for should be wired to one of these posts.  Typically 12 to 14 VAC is what's required.  

Terminals 1 & 2 are probably NC, Normally Closed, if your powering a Green / Red Block signal the Green wire goes to the NC contact.

Terminals  3 & 4 are probably  NO,  Normally Open,  the Red signal light wire goes here.  

Keep in mind DPDT relay means  Double Pole, Double Throw, the DP - Double pole part refers to having two INDEPENDENT sets of contacts.     Terminal 5 distributes power to,  3 and 1, and has nothing to do with Terminal 4, which is controlling and distributing power to contacts 2 and 4.

If you have a small DC train transformer, like an HO set it to 12 volts, hook the positive side to either terminal 7 or 8 and the other side or ground side of the DC transformer to your U post, or outside rails...  If you don't have this type transformer, you can use a wall wart 12 volt transformer, or as GRJ noted you'll need a diode like an IN4001 and a capacitor to convert the AC to suitable DC power.   

If all this is beyond your technical abilities, reach out to me via my email, and I can provide you with a 12 volt AC relay...

Hope this makes it clearer and not more confusing. 

Chris A  

overlandflyer posted:

ah... what an abysmal site... here is the LY data sheet.... pinouts near the bottom.

http://www.ia.omron.com/data_p...4_8_csm54.pdf?id=949

i wish people would read stuff before responding.  if you want to guess, be my guest.  if you want the data sheet, here it is... again.

Why the vitriol, his guess was correct, and so was mine?  FWIW, I looked at a similar relay before posting to be sure.

I am thinking that for sure it is AC because I remember when I bought it the cost was way more than DC relays.   Another supporting reason, and probably more significant, is that I'm pretty sure that I used it to turn power off/on going to 2 different sidings.  The wires that I still have connected - I have markings still on 2 of them that say "Track +".

I will take a side shot when I get home.  I will look for markings and report what they are.

A terminology question I am having is the use of the term "solenoid (electro magnetic coil)".  When I said that I thought 7 and 8 powered the relay, is that the same as using that term?

I'll come back with better info later.  Thanks to all of you.  There's a lot here for me to digest - sorry that I'm not more "intelligent" when it comes to electrical terminology and components.  For an example, I actually had to take time to think what "normally closed" means.  I think that NC means it's letting power go thru, right?

- walt

Most relays have the schematic imprinted on the side,albeit hard to see. 

I took the asked for picture from the side.  I also wrote on a piece of paper (and took a photo of it) all of the markings on the side.

I also need to slightly amend my above comment about 'wires'.  Other than the 2 that I call the ones that are powering the relay, here is what each wire says:

Post 3: "Track Stage +"

Post 4: there's just a wire connected to it but no markings so I don't know what it is.

Post 5: "TIU +"

OK, here are the pictures:

As always, thanks - walt

The round thing is the thing you power to actuate. The solenoid and takes 12 vdc

Yes Walt, putting 12 Volts DC across terminals 7 & 8 energize the electromagnetic coil, which is the white round cylinder marked 12 VDC.....    When the coil is not energized with 12 volts, a small tension spring inside pulls the contacts over so that the Normally closed NC contact is getting voltage.   In otherwords,  terminal 5 is connected to terminal 1.   

When your train enters the insulated rail section, the metal wheels and axles bring ground to the other side of the electromagnetic coil.   In this condition, the electromagnetic coil overcomes the tension spring and moves the contacts from NC Normally closed position, to the NO normally open position.   Green light goes off, and the Red signal light comes on.....   Terminal 5 is now connected to terminal 3

WOW, I really don't remember powering the relay with a DC supply.  And to imagine it was only 15 years ago

OK, I have an HO DC trannie to use for that.

Is this interpretation of all of these great pieces of advice correct, relative to the original diagram provided by John, which I will show here:

POST 7 & 8: power from trannie (since it's known now to be DC, does it matter which post is ground and which is plus?)

POST 5: power from (using John's diagram) center rail (I will power directly from ACC '+' post on my trannie that I power switches with)

POST 3: Goes to green post on the light

POST 4: Goes to red post on the light.  Or should this be POST 1 as hinted at by the preceding poster??

POSTS 1 and 2: not used.  If POST 1 is supposed to be used then I'm guessing POST 4 isn't used????

If I have 3 and 4 backwards then I know to just reverse the wires at the light.  I'm dumb but not that much

Ground to the light is as shown, or in my case from the COM post on the trannie for switch power.

Do I have it???

As always thanks - walt

walt rapp posted:

 

Do I have it???

Not quite right.

First, a relay is a switch just like any other switch. There is an input side and an output side. For a DPDT switch, the input side is the DP (double pole) part and the output is the DT (double throw) part. Here's a diagram of the possible connections:

Note that the double poles are posts 5 and 6. The dashed line in the diagram indicates that the throws are physically connected but not electrically connected; they act together but are otherwise electrically independent. Therefore, the posts on the left side of your relay are electrically independent of the posts on the right side of your relay.

Second, you seem to be under the impression that a relay requires a continuous source of power. That is not the case. The coil of the relay is normally off and remains that way until you want to throw the switch by applying power. In your case, posts 7 and 8 are used to activate the relay; the electromagnet powered by the coil is turned on and the switch connections are changed.

When there is no power to the coil, there is a spring that holds the contacts in place so that you have a connection between the relay common and the normally closed output. Activate the relay and the switch changes so that now there is a connection between the relay common and the normally open output.

Remembering that a DPDT switch has 2 independent circuits that act together, in the first circuit, post 5 is the common, post 3 is the normally closed, and post 1 is the normally open. In the other circuit, post 6 is common, post 4 is the normally closed, and post 2 is the normally open.

EDIT: --------------

Sorry, I've got this diagram wrong. As the other folks have expressed and according to the data sheet, the normally closed would be posts 1 and 2. The normally open posts would be 3 and 4.

Here's one way to rig your signal with the relay and DC transformer that you have.

First, setup the power supply so the relay will activate when the wheels of a train pass over the isolated section of track.

I don't know which posts on the relay are correct in terms of polarity so you may have to change the connections to posts 7 and 8. One way, they will work, the other they won't. If you test it directly off the power supply, before wiring it all up, that will give the proper indication. Either the relay will click on or it won't.

Then make the connections that will power the signal from track power.

Or you may want to use accessory power for the signal.

EDIT: ----------------------------

Sorry again. Due to my previous mistake about having the NO and NC posts on this relay reversed, I have revised the signal connections to their proper orientation.

After reading all of the posts and actually taking the time to study them all, I set up a little test track.

With all of your help, I FINALLY GOT IT WORKING

THANK YOU, THANK YOU, THANK YOU!

As always, a grateful walt

Many of us have struggled with this very topic.  Perhaps one of the individuals who responded could craft an article for OGR.  There seems to be several alternatives available, it would help some of us going forward.

There are other alternatives to doing this including:

• Using AC power with a bridge rectifier, smoothing capacitor, and voltage regulator. GunRunnerJohn has developed just such a circuit and they are available here.
• Adding a smoothing capacitor (polarity sensitive) to the coil connections of the relay will tend to hold off any problems with relay chatter caused by the wheels rolling over the isolated track section.
• Because this relay is a DPDT type switch, and the block signal only uses half of the available outputs, the other half can be used for a panel indicator, another accessory (gateman, crossing gates, etc.) or even to route power to another block of track. The voltage is independent of the other connections.
• Buy the cheap relay modules from sellers on EBay. At about $1 per relay, they are able to carry current up to 10 amps apiece. They will require DC power 5v or 12v for the module itself.

I'm glad that Walt was able to work something out. I'd sure like to see it in operation. Any videos available???

Here is my solution.  It varies from all of those suggested above.  I'll also discuss why.

First there was this suggested solution:

But that solution was offered when it was still thought, because I said it was, that the relay was an AC relay.  It was subsequently found to be a DC relay.

Then there was this:

But it's incomplete in that it does not show a few things:

1. the DC power source

2. How the relay contacts would get 'triggered' when the engine hit the insulated rail.  In this diagram, the light would forever stay green.  

Here's my solution which combines the thoughts.  And then I have a BIG question.

My BIG question is this: Is this safe????   By that I mean having the DC power pack connected to the rails which are AC power coming from the Train transformer.  But note that the wire connected directly from the DC supply to the rail is going to a ground rail.

It works, I know that.  But I'm concerned about keeping the power on for longer stretches. 

I'd like to also remind: I'm not interested in spending any more money on solutions.  If Radio Shack still existed, and we had 3 or 4 local shops, I would be less hesitant to buy inexpensive things.  But since they don't exist most electrical parts suppliers only sell larger quantities when I would only ever need one, and put shipping on top of it - sorry, but I'm just not going to do that.  I had the relay so I thought I would try.

Thanks for all of your help and understanding of my lack of electrical components.

As always, thanks - walt

That shouldn't be a problem. The power only flows through a completed circuit. Almost "mysteriously" the electrons know where to go.

As long as the DC supply is transformer isolated from any other power source, it should affect anything.

-----

I am confused about the Radio Shack comment and not buying mail-order.  I find it far cheaper to buy mail-order, even when Radio Shack actually had parts. 

The biggest mail-order parts supplier actually sell almost everything in quantity one if you desire, for small quantity orders, First Class Mail shipping is around $3.50-$4.00, hardly a King's Ransom.

Digikey or Mouser are my go to places.  If you're patient, you can also get tons of stuff from China with free shipping, and those prices are generally even cheaper.

Walt: The diagram below was also in a different post in this thread but maybe it didn't actually show up. Sorry about that. I've been having trouble with downloading pictures lately. I must have missed the problem. Anyway, the diagram is the same as what you've come up with on your own. I think you may have a bit more practical knowledge for electricity than you're letting on.

The answer is YES; this arrangement is perfectly safe. As @stan2004 wrote to me when I asked him about running AC and DC through the same conductor, he responded: "It's like two ships passing in the night". I had my doubts but Stan is known for, not only giving good advice, he likes to put his answers to the test. He built a test circuit and made a video to prove the concept.

So I think your good to go. I'm glad you were able to work this out.

Thank you for putting my mind at ease Scotie and John!!  Much, much appreciated.

John, I can't remember the last thing that I looked for at Mouser but I had to buy something like 50 or 100 and there were no smaller options.  I needed 2.

Maybe for some things 'one' is available but not for the small things that I looked for.  I don't really buy electrical things hardly ever, not the kind anyways that I can't get at the big box home stores.

I believe this topic can FINALLY be put to rest thanks to all of you for helping out.

As always, thanks - walt

Leo,

Just a FYI, I can see all your pics, doesn't appear to be anything missing here.

Thanks Tom! I wasn't quite sure. That's good to know.

Consolidated Leo posted:

Walt: The diagram below was also in a different post in this thread but maybe it didn't actually show up. Sorry about that. I've been having trouble with downloading pictures lately. I must have missed the problem. Anyway, the diagram is the same as what you've come up with on your own. I think you may have a bit more practical knowledge for electricity than you're letting on.

The answer is YES; this arrangement is perfectly safe. As @stan2004 wrote to me when I asked him about running AC and DC through the same conductor, he responded: "It's like two ships passing in the night". I had my doubts but Stan is known for, not only giving good advice, he likes to put his answers to the test. He built a test circuit and made a video to prove the concept.

So I think your good to go. I'm glad you were able to work this out.

Thank you for the confirmation and updated diagram.  If it was in this thread earlier I apologize for missing it.

- walt

Leo, you are most welcome! I have had trouble myself and it's sometimes nice to get verification from someone on the outside so to speak.