One last time here is a post written by a friend of mine some years ago on the other major three-rail forum. I re-post it here to try to help folks who wish to know the facts about the confusing Lionel "small black transformer with the orange handle on the side." You may encounter them on either the primary or secondary markets and need know what you have, are seeing, or are considering purchasing. Photos alone, especially those taken of the front only, can be very confusing.
I have taken the liberty of doing some editing and updating and attempted to remove all opinions.
Two things I would add to his 2008 post are that the newest production of the real CW-80 will now operate on both 60 Hz current (standard in the USA) and also on 50 Hz current (of the proper voltage) which is standard in much of Europe; and that the term VA equals Volt-Amps equals actual watts deliverable to the track.
-------------------Quote, with ammendments:
This post is intended to help owners and prospective buyers to distinguish among the several look-alike small transformers that Lionel® has produced in recent years. It is confined to the small "black ones with the orange handle on the side." (If you want responsible answers to questions on this subject, or desire to make you opinions known, you MUST specify which of the following models and/or versions you are discussing.) The term "specs" is used for "specifications" as transcribed from the official http://www.lionel.com/ website as of July 21, 2008, and beyond.
These data are offered for reference only. I have minimized opinions here so for the most part these are verifiable facts. Volt-Amps (VA) may be read as as "watts" more of less. V means volts; A means amperes or amps. All specs are alternating current. Any of the following types may possibly be found in "sets" or offered for individual sale by dealers, auction houses or private citizens. There is no such thing as "The CW-80" There are several versions of CW-80 and even more look-alikes. You need to know exactly what you are buying or posting about:
1. CW-80, Revised. Product number 6-14198 Output Specs: 18 Volts, 80 Volt-Amps 5 Amperes. Has four output terminals on the back. In production since 2006; corrected the problems with he early version. Voltage of accessory output factory-set at 12 volts but can be changed by owner. Black posts marked "U" are "common;" Red posts marked "A" and "B" are "hot." "G" prefix to date code.
Edit/Addendum: suggested by Phil (pmilazzo) and Nicole (N.Q.D.Y.) in posts below: Recent production of this device was modified to be able to run on either 60 Hz AC "house current" (standard in most of USA) or 50 hz AC current as used in many other parts of the world. This modification is indicated by a sticker that reads: QC50-OK. In the absence of this sticker use with 60 HZ current only!
2. CW-80, early version.. Product number and specs exactly the same as above, except that the Black posts marked "U" are hot; Red ones marked "A" and "B" are common.(Evidently all examples of this original version were factory miswired.) Considered to have been manufactured under poor quality control. Generally considered to be prone to immediate or early failure. Owner's Manual confusing and inconstent. This version has an unusual rate of problems for a modern electronic device.
3. CW-30, aka PowerMax 6-14275 18V 30VA 1.8A. No accessory terminals. Evidently the post marked "U" is common, "A" is hot.
4. CW-40, aka PowerMax Plus, 6-24253 18V 40VA 2.4A. No accessory terminals. Posts as in 3, above.
================================================
In addition to the four listed above, as of this update there are two Lionel controllers that appear similar to the ones above, except that they use a separate power "brick":
5. BW-80 6-14003 18V 80VA 5A Has accessory terminals factory-set at 12 volts; cannot be changed by owner. Not known by author which terminals are common. Check with Owner's Manual or use ohmmeter. Predecessor to CW-80. Only produced for a year or so back around 2000. Relatively rare.
6. GW-180 6-37947 Brand new design (late 2012.) Much more power than any of the other "look-alikes." Like the older BW, it also uses the familiar small "black case with the orange handle" and a separate power "brick." Input: 120 VAC 60 HZ ONLY. AC Output 18 V, 180 VA. (Specs taken directly from Owner's Manual.)
That's it -- to the best of my knowledge -- except for the general cautions to know exactly what you are looking at; don't expect to get perfectly accurate voltage readings on devices that utilize "chopped waveforms" from non-RMS meters; and don't believe everything you read on the forums.