Multiple transformers on the same layout/section of track Article left out PHASING! Newbies Read This!!!!!

instead of a direct short between TX posts use an old style 11/2 Volt flashlight bulb. More Better.

Be careful with generalizations!  On some older (but still used) transformers, the U post is not the same as it is on newer transformers.

Chuck

@PRR1950 posted:

Be careful with generalizations!  On some older (but still used) transformers, the U post is not the same as it is on newer transformers.

Chuck

Example:  1033 transformer.  U post goes to center rail

John

You can nitpick, but the important part is your transformers connected to the same piece of track MUST be phased correctly.  A new hobbyist probably has no idea at all of the importance of proper common source transformers having their secondary's in phase.  Yes, you guys are correct, the U post is not always the U POST!  A even better example of this is the early CW-80 transformers. U on them is not like U on a ZW or Z etc.  Lionel was given plenty of timely advice to be able to correct this, the CEO at that time just chose to ignore it.

They had in their possession a 30 page detailed engineering report including graphs, heat transfer curves, and a slew of other data supporting the claim that this transformer' electronics would fail like crazy.  Guess what?  The electronics did fail like crazy.  John Brady never ignored my advice again!

Don, I want to ask you specifically about the ZW. I have been running my locos on one circuit with that one handle maxed out, but am finding that with heavier trains or MUs, that the voltage dips to ~ 16, and maybe sometime less. If I parallel in another circuit from that same ZW, will they be in-phase?? (yes, I'm a bit of a newbie!) I have additional circuit breakers to the track, so I'm not relying on the ZW breakers.

All the ZW outputs use the same internal source of power, so there is no advantage to wiring them in parallel. Yes, they are in phase, but you can't add them up and get more power.

Thanks Arthur. Very helpful!!  As my brother would say, "you can't get blood out of turnip".

I do have some small parasitic loads (lighting for example) that I could remove from the ZW.  If I read your post correctly, though, I may be able to add another power source in parallel, such as a 75 watt single-handle Lionel transformer so long as I phase them. Did I read that right?

No, you can't practically add another transformer. The only solution is to get the power from a larger transformer.  But a ZW, with 275 input Watts, providing, on its best day, 190 Watts of output power, ought to be enough for any reasonable train. Unless you're running many MU'd locos and lots of lighted passenger cars. It's probably time to convert to LED's

@donhradio posted:

You can nitpick,... ...the U post is not always the U POST!

The "U" post is always the "U" post.

However, the convention up until the MW transformer was introduced, with very few exceptions, is the "U" goes to the center rail Lockon clip 1, the "A" post(and frequently some optional post for lower voltage operation) is common on single train transformers.

"U" is common on multi-train transformers(Type R is an exception).  This is very important when phasing power supplies.

@donhradio posted:

A even better example of this is the early CW-80 transformers. U on them is not like U on a ZW or Z etc

The original CW's have the red posts common(A & B), later units (2006-up)have the black posts common(U & U).

If the original CW(OR any CW, for that matter) was connected with "U" to the center rail, the whistle & bell functions would be transposed. The work-around for using the early CW on common ground layouts, using "A" & "B" as common, works well as long as you accept that the whistle & bell functions will be swapped.

Arthur,

Understood. Thanks. Last question: If I understand correctly, the ZW is 275 watts whether used all on one channel or split amongst the four. Correct?

My trains seem to run fine, but when I see all the newer locomotives listed to run at 18 volts, I was concerned when I read 15 or 16 volts on the app. I don't know the tolerance for running out of spec with lower voltage and thought I should do a little research.

Thanks again. Bob

@endless tracks posted:

..the ZW is 275 watts whether used all on one channel or split amongst the four. Correct?

The 275 watts is the input rating at the AC mains, the ZW, any version(250 or 275) 1948-1966, will put out 190-200 watts continuously as tested at full load.  The output voltage will fall off somewhat as the full load is reached... completely normal.

"My trains seem to run fine, but when I see all the newer locomotives listed to run at 18 volts, I was concerned when I read 15 or 16 volts on the app. I don't know the tolerance for running out of spec with lower voltage and thought I should do a little research."

As long as the locomotive works, lower voltage is never a concern.  This 18V is not a specification, but a general recommendation.  Most command control locomotives do just fine with lower voltages as a general principle.

Thanks for the info. I guess I'm in better shape than I thought!! Always something to learn here....that's for certain!

Just as an FYI   Phasing is important in newer transformers too.  Just because the transformer has a polarized plug doesnt mean the phasing doesnt have to be checked.  We run the layout with 18 Z4000's for power  One of those Z4000's had its internal wiring reversed and the polarized plug put it out of phase with the others   The transformer was powering different section of the layout but when a passenger car bridged those two power districts through its pickups there was 40 volts to the track  Poof went the engines electronics