When wiring a Lionel layout with multiple transformers, it helps to know the pinouts, or what posts output what voltages. Lionel published a few lists over the years but none were complete. Here is my list of 33 different Lionel transformer pinouts.

When you use multiple transformers, first you need to phase them. Once you phase them, you wire them consistently. The legends on the transformer don’t always match the internal wiring.

The common post goes to the outer rail, and you can connect the commons on all of your transformers together. Then you can run the hot post from each transformer to the center rail of the track you want to use it to control. Ideally, use a dedicated transformer for accessories that gives a useful fixed voltage with some combination of the common post and another post.

Without further ado, here’s my list of 33 Lionel transformer pinouts.

transformercommontrack 1track 2accessories
1010rightleftN/AN/A
1014rightleftN/AN/A
1015rightleftN/AN/A
1016rightleftN/AN/A
1025rightleftN/AN/A
1026rightleftN/AN/A
1032AUN/AA-C
1033AUN/AA-C
1034AUN/AA-C
1041AUN/AN/A
1042AUN/AN/A
1043rightleftN/AN/A
1044AUN/AA-C
1053rightleftN/AN/A
1063rightleftN/AN/A
4045rightleftN/AN/A
4050rightleftN/AN/A
4090UAN/AB-C
AAUN/AA-C
KWUABC-D
LWAUN/AA-B
QAUN/AA-C
RACFA-D
RWAUN/AB-D
SWUADB or C-U
TWAUN/AD-A
VUADB or C-U
VWUADB or C-U
ZUADB or C-U
ZWUADB or C-U
SAUN/AA-C
4150rightleftN/AN/A
CW-80UAN/AB-U

What about Marx transformers? Here’s the general rule for those. You can use Marx and Lionel transformers together and that can be a good thing, since Marx transformers are usually really cheap.