Output Issue with LW Transformer

Attached is the wiring diagram. I would start with this and go through the wiring.

 

Thanks for the wiring diagram, Joe.  The wires and connection points all look good. There must be some contact point that I am missing.

Circuit breaker? Certain transformers the light will still light

The LW transformer is a tricky one. And, it's a weird design, starting with the speed control that seems like you're moving it backwards to increase the voltage!

My personal opinions aside, one thing that is not mentioned in the Service manual and the wiring diagram, is that once you remove the inner metal frame [with the terminal plate ***'y [pt. # 22-34] still attached to it]  from the base plate ***'y [pt. #22-41] you 'll  see a thin protruding metal strip that is riveted to the 'U" post. This metal strip extends to the rectifier bracket ***'y [Pt. # 22-66] where the terminal end of it MUST make contact with the corresponding terminal on the rectifier bracket ***'y!

Now, i you re-assemble incorrectly, you'll get no variable voltage. And that's is easy to do, since the metal strip must be situated BELOW the rectifier bracket assembly's contact , NOT ABOVE it, to properly activate the 'direction' function. And it is a bit tricky to get it into its correct position once the transformer has been taken apart. You see, your 'U' post would now be isolated from the core and the current, so, a re-assembly with this metal strip incorrectly ABOVE the terminal on the rectifier bracket ***'y, will put your transformer in constant 'direction' mode!

That thin metal strip is what makes and breaks the current to activate your 'direction' control. Make sure it's situated BELOW the contact point on your rectifier bracket assembly . Needless to say, make sure both contact points are sparkling clean.

I might add this design and subsequent problem with it drove me crazy many times, and I only figured it out because I had another  working LW transformer on my bench to compare!

Should you need to look further, I can only say to check to make sure all wiring is properly soldered and that there are no 'cold' solder joints which may also interfere with current flow.

Good luck, I hope this helps. Call me if I can be of any further assistance

Len Carparelli/  L & L MTC LTD /201 438-1266

 

 

 

 

 

For some reason on my post the word "***y" should be the word 'assembly'

Don't know why this happened!

 

Len Carparelli posted:

For some reason on my post the word "***y" should be the word 'assembly'

Don't know why this happened!

Most likely the automatic censor making an assembly of itself.    

As for the LS,  I've sidelined all of mine precisely because of that reverse control business.  I've had incidents where I've asked folks to slow down a train and a wreck results because they turn the handle in the usual direction and full power is applied. 

Mitch 

Len Carparelli posted:

The LW transformer is a tricky one. And, it's a weird design, starting with the speed control that seems like you're moving it backwards to increase the voltage!

My personal opinions aside, one thing that is not mentioned in the Service manual and the wiring diagram, is that once you remove the inner metal frame [with the terminal plate ***'y [pt. # 22-34] still attached to it]  from the base plate ***'y [pt. #22-41] you 'll  see a thin protruding metal strip that is riveted to the 'U" post. This metal strip extends to the rectifier bracket ***'y [Pt. # 22-66] where the terminal end of it MUST make contact with the corresponding terminal on the rectifier bracket ***'y!

Now, i you re-assemble incorrectly, you'll get no variable voltage. And that's is easy to do, since the metal strip must be situated BELOW the rectifier bracket assembly's contact , NOT ABOVE it, to properly activate the 'direction' function. And it is a bit tricky to get it into its correct position once the transformer has been taken apart. You see, your 'U' post would now be isolated from the core and the current, so, a re-assembly with this metal strip incorrectly ABOVE the terminal on the rectifier bracket ***'y, will put your transformer in constant 'direction' mode!

That thin metal strip is what makes and breaks the current to activate your 'direction' control. Make sure it's situated BELOW the contact point on your rectifier bracket assembly . Needless to say, make sure both contact points are sparkling clean.

I might add this design and subsequent problem with it drove me crazy many times, and I only figured it out because I had another  working LW transformer on my bench to compare!

Should you need to look further, I can only say to check to make sure all wiring is properly soldered and that there are no 'cold' solder joints which may also interfere with current flow.

Good luck, I hope this helps. Call me if I can be of any further assistance

Len Carparelli/  L & L MTC LTD /201 438-1266

 

 

 

 

 

Hi Len, and thanks for the sage advice. I believe I followed your instructions and still no variable voltage. Here are 2 pics. First is a pic of the U-Post metal strip and of the rectifier bracket assembly.  The second pic shows the metal strip BELOW the tab on the assembly.

What am I missing?

 

Mitch, your wisdom is always right on!

Does the handle light very with the handle? Do you get track voltage when you by-pass the circuit breaker?

Granted, the LW has an unusual CCW direction to increase voltage versus CC for most transformers.  I solved that issue by installing only LW transformers and have three on my layout.  It was too confusing mixing an LW with CC transformers.

I did not want to give up the LW high output wattage and is probably Lionel's most  powerful single control transformer and it runs two trains per loop with one LW with ease.  They have a lighted dial too.  Their cost is light on my wallet too.

Charlie

Chuck Sartor posted:

Does the handle light very with the handle? Do you get track voltage when you by-pass the circuit breaker?

I will check when I get home tonight, Chuck.

 

Choo Choo Charlie posted:

Granted, the LW has an unusual CCW direction to increase voltage versus CC for most transformers.  I solved that issue by installing only LW transformers and have three on my layout.  It was too confusing mixing an LW with CC transformers.

I did not want to give up the LW high output wattage and is probably Lionel's most  powerful single control transformer and it runs two trains per loop with one LW with ease.  They have a lighted dial too.  There cost is light on my wallet too.

Charlie

Charlie, I wouldn't give a hoot which way the dial turned if the bloody thing would work

HCSader73 posted:

For some reason the power is not getting through the U-A1, U-A2,  U-B, and U-C circuits

Pete,
Your previous readings show that the return path through the "A" (common) terminals and the circuit breaker exists. And that the windings are intact for the (nominal) 18V "B" terminal, and 14V "C" terminal.
This leaves only one path to check (if the whistle button is not pressed). From the wiper arm connected to the control handle, through the whistle switch contacts, to the direction switch contact previously discussed, then to the "U" terminal for the track.

(The variable "U" terminal is only used in conjunction with the "A" terminals)

Dave

Have overhauled several LWs including removing the top frame from the bottom and thought I was getting pretty good at it until I ran into the same problem with one that would not put out any voltage from the U post and was about to give up on it when I noticed where the metal strip contacted the rectifier plate there was a burnt spot between the strip and plate causing poor contact and high resistance. Got in there with a small auto points type file, pressed up on the strip with a screwdriver and inserted the file between the strip and plates until I got a smooth service between the two. Started working ok after that. 

Make that a smooth  contact surface between the strip and plate.

Chuck Sartor posted:

Does the handle light very with the handle? Do you get track voltage when you by-pass the circuit breaker?

The throttle light varries with the turn of the throttle. No track voltage bypassing the breaker.

You guys are awesome, but there is no joy in Mudville.  

I detached all wires and carefully resoldered them. I cleaned the contact from the throttle to the core. The wires are all correctly situated.  I cleaned the contacts of the so called "U strip" and the tab beneath the the direction/whistle assembly. The "U strip" is beneath the tab. The throttle light dims as the throttle is turned clockwise. The A1-B and A2-B reading is 20V. The U connection readings are all less than 1V.

There is one little thing that is wrong somewhere. What else can I do?

So the handle light is off at 0, and then increases as the handle is moved up? About the only thing left is one or more copper contact rivets is loose/corroded.

If you can't get it, you could ship it to me, I would only charge shipping. I would like to find the problem that is stumping everybody.

Based on what you have said, it's in the whistle switch. Check the continuity from the wiper arm to the tab of the direction switch.

Dave

Well, brothers, I couldn't solve this issue, so I sent the transformer to Chuck.  Here is his description of the problem and solution: The problem was the leaf contact on the reversing button. Had a 1/16" gap between contacts when assembled. When out or not fully mounted it looks good, until the pegs that hold in place on the coil bracket, then it pulls the contacts apart. Checked whistle and other circuits. Good. I never would have figured this out,. So now I have the transformer back from Chuck and it works fine. The whistle and directional unit work well too. I am not sure exactly what a leaf contact is, so it is hard for me to picture what Chuck was describing. I repeated it here so that all of us may benefit from a solution to the mysteries of this cantankerous transformer.

Glad to hear you got the problem solved. Kudos to Chuck on a job well done!

- Lenny

The metal strip referenced earlier is more or less a leaf contact. They can be found in various forms throughout PW lionel; uncoupling/unloading controls use them, #90 etc. They may or may not have "contact points" on the leaf. Mostly folks ignore mention of the actual leaf and simply reference them as points or contacts.