constant voltage cord for 027 switch

No Postwar O-27 switch has constant voltage plugs.

Are you referring to the O Tubular switches like the O22? If so, the part number 711-151 or 6SP-5132-152 is what you are seeking and widely available from most any parts dealer.

Additionally, while I personally think a lot of the offerings are sacrilege,  @TinMan3rail has dual conductor pig tales that can power both the track and switch independently through the fixed voltage post ( https://www.tinman3rail.com/?page_id=423 ). I've used them extensively on my layout.

Just for clarity;

Lionel 027 switch 

Lionel "0" gauge 022 switch 

bmoran4: thanks for your help and clarification. 

A switch in the 027 series can be modified for fixed voltage operation, but you need to do some surgery and soldering. Anything is possible if you don't mind doing the work.

A.P.Bloom. Thanks for the post. I did see a Lionel video of what I think you are referring to, where you cut the wire connecting the 2 coils and connect the new wire to it. 

I haven't done it in about 40 years, but...yes...that's the theory. You find the spot where track power (middle rail) is connected to the common between the two coils. Sever that connection, add a suitable small connector (4th binding post, small socket, etc) and power the coils directly. They look for a "ground" from the outside rails (for non-derail feature) or through the controller contact(s) for normal operation.

The 4th binding post can be installed in the side of the plastic switch motor housing, with a suitably long wire pigtail inside, to allow removing and replacing the cover. 

A person I knew back in the day connected the common coil connection to the outside rails inside the switch, and used binding post #1 (counting from the switch housing) to provide the "hot" connection, which allowed the conversion without the need to install a 4th BP.

Basically, the HOT and NOT feeds are reversed. Since we're talking AC here, the motors (coils) don't know the difference. They are not polarity-conscious.

The connection trace from the track power to coils on the 1122 can be severed with a small slice to the underside allowing for modding without disassembly beyond having the cover off or handling the coil windings. You kinda have to see the trace position on an open one to know exactly where. (I opened one, cut it,(&  cut bottom cover) then I could cut the others by eye.

I just noticed the "0-27 sw" above is a later 5122 with an odd post on it compared to pw.  I've never seen one of those "brown ones" with a light so is that for switch motor power?  The "extra" post seems to have a boss and may not be a homespun...? 

Adriatic posted:

I just noticed the "0-27 sw" above is a later 5122 with an odd post on it compared to pw.  I've never seen one of those "brown ones" with a light so is that for switch motor power?  The "extra" post seems to have a boss and may not be a homespun...? 

No extra posts on the one pictured. Same three normal binding posts, three rivets, a manual lever, and a cover screw.

I wanted to re-wire my 5121, 22 to constant voltage. I did surgery on one but this doesn't stop the anti-derail circuit from energizing the solenoid. I wish I had gone with O22's.....

I've looked at adding capacitor's but the switches would have to come off the layout to do it. Not ripping the layout apart unless I'm doing a total rebuild.

RSJB18 posted:

I've looked at adding capacitor's but the switches would have to come off the layout to do it.

I don't think you need to take them up...

Here are screen shots from this video. You've already done the hard part.

Are these what the OP is referring to, the 1122's with the extra wire post on the switch housing?

@Penn-Pacific posted:

Are these what the OP is referring to, the 1122's with the extra wire post on the switch housing?

I hope not. Those are just the one-year-only 1952 versions and those "extra posts" are the light bulb socket brackets.  The 1952-1969 versions below eliminated this quick-change feature(along with a nearly complete re-design).

The OP mentioned "plugs into the side connector", so he was probably referring to the 022 switch.

Rob- I have that video bookmarked already. I'd still have to change mine to aux power first. I did one to try it but didn't do the one's on my layout.

I have one of the 1122's on my layout too. Same as the 5122 except for the lantern.

Bob