What happens when I press the "direction" button

I'm sure there's a way, the direction button merely interrupts the power until it's released.  If you just run the track power center lead to the other end and through a normally-closed pushbutton, it'll do the same thing as the direction button on the transformer.

As GRJ says a momentary pushbutton should do the job.  Look for an SPDT type which will have normally-closed contacts that open when you push the button.  There are many handsome looking SPDT pushbuttons on eBay for less than $2 shipped.

I assume you're aware of the Z-4000 remote control that would allow walk-around direction control - though pretty spendy if all you need is direction control!

But if you're interested in walk-around direction control rather than just from the other side of your layout you can cobble together some eBay modules for less than $10.  The idea is a wireless relay that "opens" when you press the remote button.  The wireless relay module is powered from 12V DC which can be derived from the Z-4000 14V AC accessory voltage using voltage converter modules.  Like a pushbutton the relay has SPDT contacts which open/disconnect when active.  Can shave some cost if willing to do some soldering or have a voltmeter.

OK, thank you very much GRJ. What I need to find now is a SPST normally closed relay that I can mount to under the table and wire in a momentary switch to activate it. Anyone have leads to a relay that will work?

thanks

Frank

If you don't want to mess with AC vs. DC take a look at this contemporaneous thread which recommends this 12V AC relay that has the normally-closed contacts.  Since you have a Z-4000 you can power the relay with 10V Accessory AC and simply run a single-wire (via an SPST momentary pushbutton) from the outer rail "ground".  10V is sufficient to activate the 12V relay.  By doing it with a relay you don't have to run heavy duty cabling out to the switch since only control current are involved (milliAmps instead of Amps).

Thanks, can you email me the link to that relay direct to choochoo@technologynation.us  I clicked on the link in that thread and it takes me to a removed page. It sounds exactally like what I need.

thanks

Frank

Looking more closely at that automation site I found this part number, 781-1C-12A         . However I have no idea if it is normally open or closed.

The one you list above is a SPDT. It's a C-form contact so it has both NO, NC and COM. Just wire it to the COM & NC terminals. However, it's not a DPDT like Stan pointed to if that makes a difference? I see farther up you only wanted a SPST so you should be ok with the number you picked. There is a schematic on the side of the relay showing the proper terminal numbers to use on the base or you can plug the relay in base and ohm it with your meter.

For some reason on the Automation Direct site you can not link directly to a specific page or part, no idea why? Others have tried and also failed trying to link there.

Stan, those really are very nice relays although they can't come close to the prices of the ebay stuff. These are what I used in my working life and am more accustomed to, but different than what is usually the norm around here. It's a lot, but they have free 2 day shipping on orders of $49 or more and they have other stuff too. 

Yup, there's something screwy about that site - the links are not "portable" so it's fruitless to share.

As rtr12 points out the relay you identified is a single-pole version (SPDT) which is all you need.  So you save a buck relative to the double-pole version (DPDT) recommended in the other thread.  Hmm, I wonder if you'll pay more for shipping!

Here's how to hook it up:

The red wires should be "fat" wires as what you'd run for track power - #14, #16, whatever.  The blue wires can be "thin" wires as what you'd run for control signals - #22, #24, whatever.  Since you're using a relay, the SPST pushbutton does not have to be "heavy-duty" since it is switching a small current.  Virtually any pushbutton you can find will have the electrical capacity but if you want to be sure just post what you're considering and someone here will confirm.

Stan's explanations are much better than mine! 

Here's a google search link to the relay.  https://www.google.com/#newwindow=1&q=782-2c-12a.  Click the top item in the search, that's the relay.

Why do you need a relay? What's wrong with just  a normally close push button? The placement  of it might be the tricky part since it would have to be   first on the main feeder  from the transformer to what ever else is hooked up .(toggles terminal blocks) You could actually put it anywhere but might requires a little more wire. Finding one heavy enough might be a problem .

Well, he wants the relay at one end of the tracks and the transformer on the other end.  Running the heavy gauge wire end to end is probably more expensive than using a $6 relay and small gauge wire.

I started that other relay thread linked to above.

Yesterday I received a couple of the Omron SPDT relays I ordered from Digikey. I haven't permanently wired them in yet but tested them last night. Work great activating various trackside signals. I use insulated track sections to fire off the relays.

These:

http://www.digikey.com/product...DC12/Z1012-ND/280369

Yep! just an option.  When I was a kid I used a screw driver between the outside & center rail.   (don't do it)

gunrunnerjohn posted:

Here's a google search link to the relay.  https://www.google.com/#newwindow=1&q=782-2c-12a.  Click the top item in the search, that's the relay.

That was pretty slick!  Wonder how Google does it and I can't? Google must have some very talented linkers on the payroll. 

This is kind of like the Digikey links from your order lists that don't work. These electrical places are quite sneaky! 

Gregg posted:

Yep! just an option.  When I was a kid I used a screw driver between the outside & center rail.   (don't do it)

I like your thinking here, but doesn't that leave black spots on the screw driver and tracks?