Errors in March, 2007, CTT

[lionelsoni]

Joseph Rampolla says in his article "Make a Smoother-Running Rail Truck", "It's critical that you choose a quality, electrolytic capacitor rated for 50 volts.  A good rule of thumb is to use a capacitor rated at approximately triple the maximum voltage it might receive."  It is not at all critical.  In fact, there is no benefit to derating an electrolytic capacitor for voltage.  If you use it at a lower than rated voltage, it will gradually lose its ability to operate at that voltage, effectively resetting its rating to the voltage it actually sees.  You will have used a more expensive, bulkier capacitor with nothing to show for it.  Especially in a situation where you want as much capacitance as you can cram into the space available, use a capacitor rated at or only slightly above the voltage you have.  Twenty or 25 volts should be plenty for an application like Rampolla's rail truck.

He also shows a 600-volt, 6-ampere bridge rectifier, which is a considerable overkill.  You could justify the ample current rating as useful keeping the rectifier cool; but there is little point to the high voltage rating.  Fifty volts would be more than enough.

Neil Besougloff makes a common terminology mistake in his article, "Old transformers:  which terminals to use".  He calls the transformer return a "neutral or 'ground'".  "Ground" could be excused as slang for "common" or "return".  But the neutral is a completely different concept, involving cancellation of return currents.  While many are familiar with the fact that residential power-wiring neutrals are grounded, that doesn't mean that the words mean the same thing.  In fact, those who take pains, often unnecessarily, to get their transformer outputs in phase with each other, actually guarantee that the transformer common will never function as a neutral!

 

[FJ and G]

Interesting. I wouldn't have known otherwise. Perhaps they could post this in their errata or erotica column.

[dwiemer]

Bob, thanks for educating those of us "less informed".  I had thought of the "neutral" thing as being bad, but was not aware of the capacitor issue.  Perhaps we could use a "Flux Capacitor" on the Delorian

Dennis

[johnandjulie13]

This is how I like to start my day! 

In one thread I am able to get articulate cogent electromagnetic analysis and witty repartee.

Bob:

Thanks for the clarification.  I continue to learn something new about electricity everytime I read your posts.

Dave:

Some of your comments cause me to laugh outloud.

Regards,

John O

[cnw1995]

I, for one, want to find CTT's erotica column...

[anjdevil2]

What could possibly be IN that erotica column???  Nude editors with classic Lionels?

Makes you think.......

[HopperSJ]

What could possibly be IN that erotica column???  Nude editors with classic Lionels?

Makes you think.......

scantilly clad engines... 

[Neil B.]

Bob and Dennis,

We struggle with terminology because our magazine audience ranges from electrical engineers to folks that are concerned that electricity will "pour off" the rails at the dead end of a track spur and onto the floor (I'm not exaggerating). We also cope with terminology that Lionel used decades ago that was inaccurate but has become accepted jargon (postwar "trestle" bridges instead of truss bridges, for example). The Lionel "U" terminals drive folks nuts, because "U" on one transformer is "A" on another.

What word would you like to see used for the wire going to the outside rail?

"Common" to some of our readers can suggest the wire is being shared, which in some wiring diagrams is true, but in others is not. "Ground" to toy train hobbyists gets confused with the ground on extension cords or "earth ground" for metal bridges, etc., on a TMCC layout. "Return" suggests, again to typical hobbyists, that AC is a one-way street.

Seriously, I'm open to suggestions!

Thanks,
Neil Besougloff
editor

[dwiemer]

Neil,  I actually do understand your dilema.  I recall a similar discussion with regard to turnouts, etc.  Perhaps, you could on the first common term word, put parenthesis around the correct word next to it, or vise versa.  Then continue with the rest of the article.  This would, I believe, subdue the critical observer, and also educate the less informed.  I for one have a lot to learn and that is the main reason I return to the forum as there is a wealth of information to be gained in it's pages.

Regardless, I appreciate your time and efforts....y'all (all of you) at CTT do a wonderful job.

Dennis

[lionelsoni]

I feel your pain, Neil.  Strictly speaking, something like "layout common" is correct; but, unfortunately, there are other commons, like the common terminal of an SPDT switch for example, which are likely not to be connected with that layout common but will be confused with it.  "Ground" has a certain appeal to me.  It is actually legitimate (in the ANSI and IEEE standards) to use that term for the frame of a vehicle.  Furthermore, in a sense, the outside rails can be said to be modeling the (literally) grounded rails of an electrical-railroad prototype.  But, as you say, some will infer, not unreasonably, that we mean an actual connection to the earth (which, by the way, is not a bad idea for a layout, though not strictly necessary).

My best suggestion is one that I have tried to follow here on the forum and is actually right there in your question, "What word would you like to see used for the wire going to the outside rail?"  It is, of course, "outside rail(s)", or perhaps sometimes "the transformer terminal connected to the outside rails".  The latter is a bit wordy, but probably doesn't need to be repeated very often, while "outside rails" compares favorably to "neutral or ground".

[Anonymous]

I was thinking about this... why not refer to it as 'Transformer Common'?  That would indicate that the terminal(s) are not always 'U' or 'A' or 'whatever letter they use tomorrow'...

It would read something like this: "Connect the outer rails to 'Transformer Common', then connect the center rail to 'Transformer Variable'."  This makes a heck of a lot more sense to me!

The problem with switching up the 'A' and 'U' as common can create a real hazard IMHO.  Just look at the older CW and the new CW.  Since they switched them, you can no longer connect 'U' from the old CW to the outter rail, you would have to connect it to the center rail and connect 'A' to the outter rail, then on the new CW you connect 'U' to the outter rail and 'A' to the inner rail... switch them with two CWs powering adjacent blocks and well... damage to equipment is quite likely to occur...

I also can't figure out why they aren't labeled 'O' and 'I', for the ZW it would be 'O1', 'I1', 'O2', 'I2', 'O3', 'I3', 'O4', 'I4'... that would make more sense to me!

Brent

 

Brent

[Jumijo]

What could possibly be IN that erotica column???  Nude editors with classic Lionels?

Makes you think.......

 

Ahhhhhh! I'm blind! I'm blind!!!!! 

[Jumijo]

Bob and Dennis,

We struggle with terminology because our magazine audience ranges from electrical engineers to folks that are concerned that electricity will "pour off" the rails at the dead end of a track spur and onto the floor (I'm not exaggerating).  . . .

Thanks,
Neil Besougloff
editor

Thanks a lot, Neil.  I thought that "pouring off the rails" thing was supposed to stay between us.

Jim 

[FJ and G]

I thought you knew about the erotica sextion...

 

 

[Neil B.]

Thanks for the feedback on terminology.

Here's another one for the "electricity pouring off the end of the rails" concept.

A few years ago, a CTT reader set up a loop of track for Take a Train to Work Day. He told me that one of his younger co-workers was absolutely stunned to learn that the track was actually electrified. The co-worker had never heard of such a concept and presumed the train was battery-powered.

Neil

[laz 57]

Thanks for the feedback on terminology.

Here's another one for the "electricity pouring off the end of the rails" concept.

A few years ago, a CTT reader set up a loop of track for Take a Train to Work Day. He told me that one of his younger co-workers was absolutely stunned to learn that the track was actually electrified. The co-worker had never heard of such a concept and presumed the train was battery-powered.

Neil

Track electrified?

WOW and I thought it was done with mirrors or magic?

laz57

[wrmcclellan]

Neil - LOL

[Buckeye Riveter]

Thanks for the feedback on terminology.

Here's another one for the "electricity pouring off the end of the rails" concept.

A few years ago, a CTT reader set up a loop of track for Take a Train to Work Day. He told me that one of his younger co-workers was absolutely stunned to learn that the track was actually electrified. The co-worker had never heard of such a concept and presumed the train was battery-powered.

Neil

I have not had that happen to the layout indoors, but several people have asked about the type or size of batteries I use for the Gardern Railroad LGB Mogul.  

BTW, if you put a 5 gallon bucket at the end of the track, you can catch some of that electricty pouring off and use it to run the trains onboard radar so that it doesn't wander off the track.  

[lionelsoni]

"...presumed the train was battery-powered."  Not that there's anything wrong with that; right, Dave?

[wrmcclellan]

The batteries in the train allow you to put lockon's onto the rails and power your accessories!

[Anonymous]

Bob and Dennis,

We struggle with terminology because our magazine audience ranges from electrical engineers to folks that are concerned that electricity will "pour off" the rails at the dead end of a track spur and onto the floor (I'm not exaggerating).  . . .

Thanks,
Neil Besougloff
editor

Thanks a lot, Neil.  I thought that "pouring off the rails" thing was supposed to stay between us.

Jim 

LOL Jim,

That'll teach you to be careful what you say to the press!

Seriously though.  Would not the use of negative (-) and positive (+) clarify things considerably?  Whether it's technically correct or not isn't the point since it's clear there is already no standard terminology.  The point is to standardize something universal that common folk already understand.

Bruce Webster

[johnandjulie13]

HA! HA! HA!  That's nothing compared to the guy who asked "How do you wind up that thing?"

Regards,

John O

[anjdevil2]

That's funny.....I always thought that this stuff was run by smoke...Every time the smoke comes out of the wires, nothing works....

[A&Y Ry]

When one is talking about low voltage output, toy train, post war transformers, they are talking about transformers, not case problems in  "E" engineering school. In CTT Neil is trying to communicate with a general population of o-gaugers and is rightly using certain terminology that although perhaps technically incorrect has become routine useage.

The common conductor from a toy train transformer is in fact a return to complete a working circuit. It ain't a "floating ground" or a "neutral" although it does share characteristics with the household neutral which is also in fact, a return. Peter Riddle author of three volumes of "Wiring Your Lionel Layout" has used the term "ground" consistently and incorrectly in his books. However he and other authors have effectively served to assist many o-gaugers with their work just as CTT is doing with their articles. It is important for entry o-gaugers to know the alternative terminology just as it is to remind them of the technically correct terms.

Many equally learned and practicing professionals use "neutral" as an alternative to "common" in toy train discussion and in actual component labeling as Lou Kovach did with the Track power Controllers.

[dwiemer]

This has all the makings of a D**b Blond Joke.  Good that we can all have  a little laugh.  Thanks,

Dennis

[Birds]

Count me in as one of the electrically challenged.  I understand the basics but some of the things people share go over my head and I have no reference point in which to ground (so to speak) what is shared.

I'm still trying to figure out how to use the soldering methods shared on the forum to plug the holes in the end of the track on my dead end sidings so that watts don't dribble out.  After all my transformer only has so many of them...

Sometimes I wish that technical articles contained a glossary of terms. 

I remember when I switched over to three rail O gauge and read something to the effect of "connect the wire to the transformer's common", I had no idea what that was.  I had one starter transformer that wasn't labeled - it had one terminal with a metal screw and one with a plastic screw.  Then I was given a KW and everything was labeled with letters!   I finally figured that if there were two "U" posts, and one "A" and one "B", then the "U" must be "Common".  After all it was the most "common" letter used...

Then I started to get some books that explained how to use transformers, wire layouts, etc. the basics began to fall into place.  When I fried my first smoke unit during a train crash I knew I was getting somewhere.  Yes, a little knowledge is dangerous.  (Now I have in-line fuses.)

I still get lost in some of the technical posts on the forum - such as Bob's most recent response in the thread on O22 switches where he is explaining "inductive load".  I understood the word "arc", but phrasing such as "when you open an inductive circuit, the rate of change of current is infinite--it stops immediately" seem like a philosophical contradiction to me.

I like the technical explanations and accurate wording, but I often need a very very simplified example to illustrate them.

Chris

[jefelectric]

The batteries in the train allow you to put lockon's onto the rails and power your accessories!

Now if you could come up with a wireless battery charger, that would be a great system!

[lionelsoni]

Bruce, the fact is that there is standard terminology.  The problem I see is that that terminology is not only not understood by many, but also misunderstood in various ways by readers who lack knowledge of the underlying physical and engineering principles.  The challenge as I see it is to use the right terms (which do exist) in such a way that we can teach an understanding of those principles adequate to solve the toy-train-running problems.

For example, I must respectfully disagree with your suggestion to use the term positive or negative somehow as a substitute for "common".  This implies that the polarity of a DC voltage has something to do with the concept of a common return.  This is not "something universal that common folk already understand", but rather something they misunderstand.  I think that this, far from clarifying anything, would only confuse those who haven't thought about it and confirm erroneous ideas for those who have.

[Anonymous]

Bruce, the fact is that there is standard terminology.  The problem I see is that that terminology is not only not understood by many, but also misunderstood in various ways by readers who lack knowledge of the underlying physical and engineering principles.  The challenge as I see it is to use the right terms (which do exist) in such a way that we can teach an understanding of those principles adequate to solve the toy-train-running problems.

For example, I must respectfully disagree with your suggestion to use the term positive or negative somehow as a substitute for "common".  This implies that the polarity of a DC voltage has something to do with the concept of a common return.  This is not "something universal that common folk already understand", but rather something they misunderstand.  I think that this, far from clarifying anything, would only confuse those who haven't thought about it and confirm erroneous ideas for those who have.

Bob,

Please excuse my ignorance on the subject.  It is obvious by my post that I only understand the basic facts and misunderstand more than I'd like to admit.   It's clear I over simplify things to fit what I don't understand and I end up sounding like one of those who believes electricity pours off the ends of open rails.  I appologize for confusing anyone with my ramblings.

Thanks for your patience on the subject.  I really do appreciate you taking the time to set me straight. 

Bruce Webster 

[lionelsoni]

Bruce, you need only look at the almost total lack of anything resembling scenery on my layout to realize that everyone here has something he doesn't understand or do well.  The strength of the forum is that we can help each other out with what we do understand, so that everyone comes out better off.