what terminal is common on the 1033?
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it should be marked U. (when looking at it, as used, the post all the way to the left).
I may be mistaken, but isn't the 1033 the Lionel transformer where the posts are opposite from the norm? Thinking that the U post on the 1033 actually goes to center (hot) rail.
Sorry to muddy the waters. I'm sure one of our PW experts will weigh in.
mlewski posted:what terminal is common on the 1033?
It really doesn't matter 'til you go add a second transformer to your layout, THEN, you should 'phase' them to get them be peaceful with each other.
Ron M
Polarity is an issue only with modern trains that have a whistle and bell. You might get a bell sound when you pulled the whistle handle.
Its obviously an issue were you using multiple transformers and had to phase them but you have a 50-50 chance anyway depending on plug orientation.
Pete
The top of the transformer has a label that explains the relationship between the posts.
A - U is for variable track voltage in the range of 5-16 volts.
B - U is for variable track voltage in the range of 0-11 volts.
If you need 12-14 volts constant for accessories, the nearest available voltage is 16, derived from the A & C posts.
The only time that the A & U post combination might present a problem, is when you need to wire an insulated outside rail to operate an accessory (with or without a relay) that needs the A & C 16 volt source. In that case, the outside rail needs to be connected to the A post, and the center rail needs to be connected to the U post. This is opposite of the way most other transformers are wired. The A post in this case is the common between the variable track supply and the fixed accessory supply.
A number of Lionel's small single-output transformers had the U post as the track power and the common was one of the lettered posts. I always found that odd, but learned to live with it. 
gunrunnerjohn posted:A number of Lionel's small single-output transformers had the U post as the track power and the common was one of the lettered posts. I always found that odd, but learned to live with it.
^---This - Most (if not all pre/postwar) Lionel single train transformers such as the 1033, RW, LW etc, the U post is actually the variable and the lettered post is the common.
For more modern electronic whistles to operate, U goes to the center rail, the lettered to the outside rails. If you get this backwards, the bell will ring instead (if equipped).
