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I acquired this transformer around 30 years ago and it has sat in the basement since then.  I wanted to try an "experiment" and plugged it in.  The variable winding seems to work okay.  I'm getting 18v fixed from the fixed terminal and variable voltage from the other set of terminals.

The fixed voltage side, however, does not put out any power.  I opened the case and the circuit breaker is functioning properly.  Checking continuity on that winding shows that ALL of the terminals seem to be going to ground.  I have the service manual, but I'm getting the sneaking suspicion that the transformer winding might be shot. 

Any ideas as to what might be going on here?  This unit looks like it has been opened previously as one of the case screws is stripped out.

Thanks

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I believe that the TW is one of a kind from Lionel in that it has two transformers and two circuit breakers.  You indicated that everything seems to be going to ground.  There should be no connection on the low voltage side of the transformer to ground.  Do you mean "common"?  In a transformer if you check for continuity everything should be tied together.   If the transformer secondary coils are shorted, when you plug it in there should be a lot of heat and maybe smoke.  I think you should be looking for an open circuit, probably the circuit breaker that protects the fixed voltage transformer. Do not give up on it.  If there is nothing that looks overheated or burned inside the case, the problem is probably repairable. If the transformer still has its original cord, that could be the biggest hazard.  Look carefully for missing or cracked insulation. It probably should be changed. 

Thanks David, yes common is correct.  As the variable side is okay, I think that we can rule out the power cord ( which looks okay). I would think that I should not have continuity between the fixed voltage posts and common.  I'm thinking that the secondary windings might be wrecked.  Can't use a smell test as this thing has been sitting in the box for about 25+ years.  Circuit breaker is closed.

Last edited by Trainman52

I tend to agree with David, TW's are pretty robust little units, rarely have I seen bad windings, if there was a bad winding its usually because of a misgiving by a previous owner overzealous with a soldering iron....if you can, check the voltage on the incoming wire to the fixed voltage circuit breaker. if the transformer has been set up for a while, corrosion most likely has set between the contacts of the thermal breaker.....

another sneaky little thing old lionel transformers like to do is the binding post stud will come away from the solder lug and lose contact all together. sometimes you can catch them in the act if they try to spin, but sometimes they will stay put and just not make connection. TW has a shared common lug with two binding post studs....you mentioned your variable voltage is working.....borrow that common binding post stud to check the fixed side

The secondary of the transformer is a single wire wound around a steel core. It may have taps. Power comes from attaching your load to the two wires coming out each end of the coil. It is all connected together.  The magnetic flux in the steel core is generating the power in the coil. If the coil has a break in it, it will not generate any power. If you use a D.C. source it will, and should, show continuity between all the leads coming from the secondary windings. Do not forget there are two circuit breakers in the TW. They both need to be checked. 

I have found through the years, the TW was the worst transformer Lionel made. Many issues. First is overheating of the transformers. The heat goes through the control shafts and warps the large plastic handles where sometimes you can't operate the variable or whistle handles because they bind on the case.  Lionel also had problems with them too, as they revised the internal wiring in 1954 and added another binding post ( There are 2 models of the TW ).  I wouldn't be surprised if the transformer went bad due to it's reputation. This model had a short production run.

Are you getting voltage out of the auxiliary transformer? Check the jumpers on the primary side, and maybe re-heat the solder connections on both transformers. Carefully clean the contacts on the circuit breaker. As harmonyards stated, check the binding posts, when you completely tighten the nut, does the post spin?

Last edited by Chuck Sartor

I have several TW's and like them. The statement above is true. "Lionel also had problems with them too, as they revised the internal wiring in 1954 and added another binding post ( There are 2 models of the TW ).  " I recently ran in to the two version problem while replacing a power cord. I got lazy and used a older TW as a guide to reconnecting wires. Did not work right. I found a diagram of the newer TW made a few changes and it now works.

Richard

Chuck Sartor posted:

I have found through the years, the TW was the worst transformer Lionel made. Many issues. First is overheating of the transformers. The heat goes through the control shafts and warps the large plastic handles where sometimes you can't operate the variable or whistle handles because they bind on the case.  Lionel also had problems with them too, as they revised the internal wiring in 1954 and added another binding post ( There are 2 models of the TW ).  I wouldn't be surprised if the transformer went bad due to it's reputation. This model had a short production run.

Are you getting voltage out of the auxiliary transformer? Check the jumpers on the primary side, and maybe re-heat the solder connections on both transformers. Carefully clean the contacts on the circuit breaker. As harmonyards stated, check the binding posts, when you completely tighten the nut, does the post spin?

There is no voltage out of the auxiliary transformer.  The variable output works fine.  I put a meter on the internal solder connections of the auxiliary outputs, as previously stated, they all give continuity to the common side of the transformer.  The breaker for the auxiliary side has continuity, but I will jump it and see what happens.  There isn't much to resolder on the auxiliary side as all of the wires disappear inside the transformer.  I don't see any solder attachments other than the hots back to the AC cord (which should be okay as the primary transformer works).  Noteworthy is the fact that I found a glob of solder inside the case.  Someone other than Lionel has been in here before.

Stay tuned.

Noteworthy is the fact that I found a glob of solder inside the case.  Someone other than Lionel has been in here before

I had a fellow bring me a transformer that he had tried to repair himself.
When he prepped the eyelets for a new cord, he broke off the primary wires leading from the eyelets into the transformer coil.
That is something to check.

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