Doing Something Wrong: Constant voltage to 1980’s O27 Turnouts

From one of your pics, I am assuming that you are powering the track lock on from the same ZW as you show connected to the switch coils. If this assumption is correct, then you have to make sure that the wire from the U ZW terminal is feeding the outer rail.

Another thought I had was, that magnet wire is coated in a varnish for insulation, so just wrapping around a wire might not make a good connection or any connection at all. The reddish wire clearly was not prepared with the insulation removed but the other wire is probably in the same condition with a clearer insulation not stripped either.

Vernon, using a razor blade to remove varnish for insulation on the turnout coil was the key. I added additional pictures for future reference. Tested originally using both train power handles. Then moved to the accessory handle and continued to work.

MED, yes I am using the same ZW to powering the track lock. Not sure what "U ZW terminal is feeding the outer rail" means. Kindly clarify. I discover that in order for the "Toggle switch" to activate the "Turnout" the track lock does need to be connected to the track. Maybe this ties into the guidance you are providing.

Thank you both.

Three turnouts were acquired for proof of concept. Unfortunately the other two turn outs have a different coil set-up. See pictures. There is one center wire but don't see any wires on the sides. Additionally there seems to be very little excess wire to pull out and connect with external power wire.

Question: Is there a way to provide constant power to the turnouts with the different coil set-up? (Pics 8 and 9)

I'm "ok" with a cannibalizing/ taking apart these switches as a trial.

When I converted all of my old Lionel O27 switches to external power, I had to remove the plate from the bottom to find the wire from the coils to the 'power' post.

walt

I have two diagrams from an O27 switch similar to yours, one unmodified, one has the modification you are working on.

Here is the unmodified switch

Here is the switch showing the modification you made

The modification pic depicts in red where you cut the wires. The green represents the wire you added and show in your pics connected to the "D" output of your ZW. As you can see in the pic, the wire you added feeds power to the two solenoid coils. Each coil requires a ground path back to a ZW "U" output (the ZW has four "U" outputs, also labeled COMMON, as shown in your pic) . Each coil's ground path is independently controlled by the controller shown on the right side of the pic. As depicted in the pic, pushing the controller arm up completes a ground path from the right coil, whereas pulling the controller arm down completes a ground path to the left coil. We have to get the ground of the O27 switch back to a ZW "U" output. Internal to the O27 switch, the two outer rails and one of the controller's connections are all connected together - thus whatever you connect to one outer rail of the O27 switch is fed to the other outer rail and the controller ground connection. So connecting one outer rail via the lockon shown in your pic to the a ZW "U" output will get ground to the switch controller. I indicated in Blue the O27 grounds that are internally connected together.

Hope I made things a bit clearer.

Next time you need to strip enamel wire, fine grit sandpaper works like a charm. I learned that from a motor kit I had when I was a kid where you had to wind your own armature.

Walt, appears I'm about to do the same.

CK, nice option. Safer than a razor blade.

MED, started getting lost here..."We have to get the ground ..." Need to read a few more times and with a fresh mind tomorrow.

Net/net seems to be getting power to the wires which leave the coil and go to the thin metal arm within the "Turnout" that connects to the center rail.

Tomorrow I'll use the Dremel to cut around the Blue tape (See Pic) to make an opening. Hopefully I'll be able to see the wires and where they connect to the thin metal arm to center rails. Depending on availability of wire underneath two options might exits:

1. Remove the wires from the thin metal arm. Connect to my wire which goes to ZW B output.
2. Solder my wires to where the coil wires connect to the thin metal arm. Create a gap/ cut the thin metal arm somewhere in between the solder wires and where the contact to the middle rail.

Does the above (1 & 2) sound logical?

• Either scenario I'll need to figure out a way to snake the 16 Gauge to the correct location and ultimately out of the "Turnout." From various articles my understanding is 16 Gauge is safe for a constant 14 Volts. 18 or 20 Gauge not unsafe but doesn't come across as the suggested Gauge. Is that a fair understanding?

For the bigger picture, should I be successful in converting all the switches, I'll have around 13 switches. My thought is to have one wire (Positive from ZW) going into a "Bus" like device and 13 wires going out (one wire to each switch coil).

I was able to make my switches work on constant voltage by applying higher constant voltage to the switch power wire from the transformer. That's the wire coming from the controller, not to the switch body.  You can select what voltage you want by selecting which terminal you power it from.

@OriginalMadman posted:

... the wire coming from the controller, not to the switch body.  You can select what voltage you want by selecting which terminal you power it from.

I'm going to need to see a schematic & photos of that...

Walt, appreciate the email, article and additional detail. The video link is nice. It seems to show a different Turnout. The "buzzing" resolution is interesting. I'll need to research and/ or get additional assistance.

CK, Used the sandpaper for my other two trial turnouts. 100% better than the razor blade.

MED, the diagram seems to be a different Turnout. My Turnout doesn't have light bulbs. The electrical insight might still apply. However still lost on the second half of the paragraph.

Since my workbench (aka dining room table) was going to be reclaimed by my wife I needed to take action.

1) Frankenstein surgery on one Turnout to open up the underside (Pic 13). With the Center Rail wire identified we moved forward.

2) Using the third experimental Turnout I used painters tape to outline the cutout area. (Pic 20)

3) Last cut made was closest to the outside of the Turnout. Didn't want to cut to deep and damage the wire. Used that side to bend the cut area. (Pic 21)

4) Picked up the safety paper. Center rail wire in view. (Pic 22)

5) Cut wire and pushed to top side of Turnout. Sanded/ cleaned wire of protective coating. (Pic 23)

6) Connected positive voltage, tested and success! Now to go back and protect the wire, run wire out of cover, re-attached cover, etc. (Video)

Hopefully this serves as a resource to help others in the future.

CK, MED and Walt...Thank you again.