Lionel model R transformer--stumped

How (where) is the choke wired?

Thanks, Prof, but no, that is for a postwar R. The prewar R is wired completely different. There is no long wire wound resistor. As a matter of fact, there is no resistor at all. The choke or secondary transformer (?) is wired to the 110 volt line and also the overload light. Unlike the postwar model this has only one circuit breaker.

Here's the pictorial diagram from the manual for the postwar version - it does look like the one 115 leg is connected to the CB, but it obviously can't be. Now I will have to look at mine and see if it is a prewar or postwar unit. I didn't realize there was a big difference.

Thanks, Rob, but again totally different. The 110 volt line cord connects directly to the circuit breaker. The choke buzzes when there is a short, then the overload lights. Very complicated wiring.

Thanks Prof. that sounds as logical as I could guess. What throws me is the 110 volts at the low voltage circuit breaker. That's a lot of voltage so close to the metal nameplate.

Indeed, the 1942 parts list identifies that transformer as R-27 "Pilot Light Transformer":

What throws me is the 110 volts at the low voltage circuit breaker. That's a lot of voltage so close to the metal nameplate.

I don't care for any of the Lionel transformers with metal cases. I don't use them, and don't recommend them to anyone.

I have a prewar Type R.  The power cord should not connect to anything but the transformer primary.  Some jackass rewired yours.  I no longer use my Type R, since the circuit breaker does not protect some of the terminal combinations, and the insulation is "tired."

No, some jackass did not rewire it, it is factory wiring as I stated in a post above.

Chuck, I stand on my statement.  You spurred me to open a prewar Type R I have sitting on a shelf.  I know it is prewar because I was given it for Christmas in 1941.  There are no wires connected to the line cord terminals except the transformer primary wires.  It also has 2 circuit breakers.  The wiring diagram Rob posted is accurate but misleading; the line cord is not connected to the terminals labeled as 2 & 3.  Also, it does not have another transformer inside.

Pictures are attached.

How do the control knobs mount, friction fit or with a set screw?

Friction fit.  The knobs have slits for proper alignment.

Ok, you have a postwar version. Friction fit knobs did not appear until after the war. Prewar knobs were exclusively set screw mount.

Addendum: I see with your photos that your transformer shafts have double splines. Prewar versions have a single spline.

Chuck, no I do not have a postwar version.  I received it, personally, for Christmas of 1941.  I know; I was there.  Maybe Lionel did a redesign shortly before the war????

Is it possible it was replaced unbeknownst to you following an operational issue/failure with a postwar version by a parent who didn't think it would be noticed?

Well ok RJR, all I can say is it has all the indicators that it is postwar. 

Anything is possible, Rob.  Just like the possibility that Lionel did a redesign and made only a few before closing down for the war.  I do recall that sometime in the 40's the red light would stay on even though the breaker hadn't opened.  My father had it repaired and told me that the repairer said a set screw was the issue.  I'm certain that if it were being replaced, he'd have proudly told me he got a new one; I also doubt that he's spend the $$ for another if this could be repaired more cheaply.

Ah yes, back in the day, even when things were just as expensive to repair vs. buying new, folks would take great pride in keeping the original piece going for years to come! My Grandfather was the same way, he instilled that same thought in my head with a lot of things! Still running a ZW Transformer from at least 30 - 40 years ago, belonged to my father in law.

It may have been replaced without his knowledge, then, too.

StillPlaysWithTrains1469 posted:

...Still running a ZW Transformer from at least 30 - 40 years ago, belonged to my father in law.

The newest ZW was made at least 50, & possibly as much as 52 years ago as of 2016! The last production run may have been 1963-1964.

I'm reviving this old thread as I just got  type R and I am also stumped. I replaced the cord inspected the wiring, everything looked good, and proceeded to test it. Both throttles provide the correct voltages but the short circuit light just barely glows. I checked with a voltmeter and the socket is getting 3.9 volts even when the throttles are in the full off position. Does anyone have any idea why this is happening?

Also I don't really like the old thermal breakers, does anyone have any recommendations for replacing them?

Also I forgot to mention it looks like the diagram that Rob provided above with 2 breakers.

@Pete in Kansas posted:

I checked with a voltmeter and the socket is getting 3.9 volts even when the throttles are in the full off position. Does anyone have any idea why this is happening?

If the breakers have not cycled recently, they may not be closing completely on reset due to dirty or corroded contacts which will bleed a small current to the bulb when under load. They should probably be replaced - 6-7 amp self resetting automotive breakers like the BUSSMANN UCB-6 should work.

When not under load - there might be some capacitive coupling, but not usually enough current to light a bulb.

Rob thanks for your quick reply. I did clean the points inside the breakers ( just like cleaning the points on an old distributor ignition car) and I will be replacing those breaker as I still don't trust them.  I did get lucky and after closely examing the circuitry going to the overload indicator I did find a broken wire on the left side of the coil like assembly that is between the 2 breakers ( I'm assuming this is a resistor?). I unwound 1 wrap twisted the broken ends together and then soldered it.  No more light and the breakers work as they should but they're slow so as I mentioned I will replace them.

This old R now makes the perfect small transformer for my small Christmas tree layout. Maybe I'm a bit paranoid but thermal breakers scare me so I also have a Marx manual reset breaker inline since this train may be run by children who might just leave it if it stopped running.

@Pete in Kansas posted:

No more light and the breakers work as they should but they're slow so as I mentioned I will replace them.

The breakers on the Type R usually fail by opening too quickly.  Unbelievably, the spec for this transformer is 3-18 seconds at 16-18 amps for the breaker test.

And that's why I use it only for primary power to a bubbling oil derrick and a flashing billboard.

Jon