1033 Transformer question

[Anonymous]

Need someone to tell me which of the four posts go to the track and what two are for accessories. Have been using a couple of old 1053's at Christmas but now have a couple of 1033's. Thanks, Jerry

[ChiefEagles]

U is common and A is center rail. Should show you on top next to the post. There are various voltages for fixed. A-C is 16V, B-C is 11V and A-C is 5 V. I have some uncoupling sections powered with 11V [B-C]. Be sure the transformers are phased if you use common ground [all hooked to outside rail].

[lionelsoni]

If you have no accessories connected to insulated control rails on your track nor switches that you want to power from a fixed voltage, you can wire A and U to your track either way, then select fixed voltages from among A, B, and C. Otherwise, wire A to the outside rails and U to the center rail. You will then have a constant 5 volts at B and 16 volts at C, relative to your outside rails.

Here is a schematic diagram:
http://pictures.olsenstoy.com/cd/transfmr/ps1032a.pdf

Having the transformers in phase is necessary only if you intend to run a train across the boundary between two blocks powered by different transformers, in which case you should also be careful to set the two transformers to the same voltage.

[ChiefEagles]

Bob, if you use more than one transformer to power various things around the track and a transformer to run trains. You use U as the common [outside rail] and, with all of those using the same common [outside rail], all transformers have to be in phase. If you do not use U as common, the whistle on post wars will not blow right. Look at your Lionel manuals.

Here is one:

[lionelsoni]

Frank, postwar whistles shouldn't care which polarity they get. What you say would apply to modern bells and whistles however; but, in that case one of the two won't work anyway.

For something that you want to operate from a fixed accessory voltage using control rails, like an 022 switch or a crossing gate, you need a voltage that is fixed relative to the outside rails. If you connect the U of a 1033 to the outside rails, there will be no voltage available from that transformer that is fixed relative to the outside rails, because the U terminal connects to the transformer's wiper.

You could, as you say, dedicate one 1033 transformer for running trains and the other for accessories. But Jerry seemed to be looking for both track and accessory voltage from the same transformer, which suggests to me that he wanted to run two trains and some accessories. I think we both agree that he can connect U to the outside rails if his accessories are not associated with control rails. But we disagree about the need for phasing except in the case I described of running between blocks.

[Chris F]

Since I was used to using Terminal U as the outside rail ("ground", or "common") connection, I was surprised to see Peter Riddle recommend Terminal A as the outside rail connection in his book, "Greenberg's Wiring Your Lionel Layout". I had to read this about a dozen times before I understood it:

"Most Lionel trains run well with 5 to 16 volts of power, so the track should be connected to posts A and U. Post A can also provide either 5 or 16 volts of fixed current in combination with B and C respectively, and is the ideal choice for the ground wire."

The 1033 is not the only Postwar transformer that often does not use Terminal U for the ground. "Be Careful Out There!"[:)]

I recommend phasing, but for a different reason. Wiring can be simplified by running a loop of wire around the layout to handle the ground return. This way you don't have to run two wires from each accessory or track connection all the way back to the transformer. The ground wires, both track and accessory, can be connected to the nearest point of the ground loop wire. Just be sure the ground loop wire is sized large enough to handle all the current (in the case of two 1033's, about 10 amps continuous).

[Buckeye Riveter]

Here are the specs from the Lion.


A clearer posting of the chart above can be seen and downloaded at:
CHART

[lionelsoni]

Chris, you can have a common ground between track and accessories with supplies that are not in phase, or that are not even the same frequency, or that are ac and dc, as on my layout. However, phasing is harmless; so phase away, whoever wants to!

[martinden]

This matter of the "U" post seems to cause endless confusion, though it's actually pretty clear-cut.

Here is the rule -- applicable to all postwar transformers that have more than two posts, except the "R" (which doesn't have any "U" posts).

On single-train transformers, "U" is the variable post (connected to the center rail), and "A" or "B" is the common or base post (to the outer rails). I'm not sure what the story is on modern-era power supplies, but for one-train postwar transformers, this rule always applies. This includes (in numbers-first, then letters, more-or-less chronological order) the 1037, 1041, 1042, 1032, 1033, 1034, 1044, 1144, MPC 4090, Q, A, S, RW, TW, and LW. On all of these, A-U is for track power; on most, B-U gives a lower voltage range.

On two-train (multi-train) transformers, the "U" posts are common, or base, and "A" and "B" (sometimes "C" & "D") are the variable posts. These include the V, Z, VW, ZW, KW,and SW. (On the first four, of course, the "C" & "D" posts are also variable.)

Just why Lionel chose to use the "U" post in two different (opposite) ways is completely unclear at this point, and we'll probably never know the answer. But once you grasp the idea, it's easy to keep the "U" and "U" business straight.

Martin

[Anonymous]

Thanks guys, I really do appreciate the info, Jerry

[ADCX Rob]

This matter of the "U" post seems to cause endless confusion, though it's actually pretty clear-cut.

Here is the rule -- applicable to all postwar transformers that have more than two posts, except the "R" (which doesn't have any "U" posts).

On single-train transformers, "U" is the variable post (connected to the center rail), and "A" or "B" is the common or base post (to the outer rails). I'm not sure what the story is on modern-era power supplies, but for one-train postwar transformers, this rule always applies. This includes (in numbers-first, then letters, more-or-less chronological order) the 1037, 1041, 1042, 1032, 1033, 1034, 1044, 1144, MPC 4090, Q, A, S, RW, TW, and LW. On all of these, A-U is for track power; on most, B-U gives a lower voltage range.

On two-train (multi-train) transformers, the "U" posts are common, or base, and "A" and "B" (sometimes "C" & "D") are the variable posts. These include the V, Z, VW, ZW, KW,and SW. (On the first four, of course, the "C" & "D" posts are also variable.)

Just why Lionel chose to use the "U" post in two different (opposite) ways is completely unclear at this point, and we'll probably never know the answer. But once you grasp the idea, it's easy to keep the "U" and "U" business straight.

Martin

And Lionel has continued this tradition on the CW-80.  The A post (along with the other red post - "B") is common, the U outputs are the variables.  As this is a 1 train transformer, this is likely the reasoning for this scheme.  Lionel still messed up the functions/labeling of the whistle/bell buttons, they are reversed when using the commons as ground on a layout.

Rob 

[Anonymous]

One other thing to consider is which combination of posts are protected by the circuit breaker and which ones are not -- assuming that the breaker in an old postwar transformer still works reliably. This issue varies from one model of transformer to another.

Those of you who can read circuit diagrams may be able to determine this from the Library at Olsen's toys and/or one of the Service Manuals, such as the ones published by K-Line or Greenberg.

My safety precaution is to install an inline, fast-acting fuse in every set of posts that I use. So far, no problems....