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Big Ed is correct! Lionel 3-rail engines are AC. Lionel 2-rail items are DC operated.
 

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The DC motors started to appear in the 70's. Later they adapted to AC with the electronic E units. Today a lot of engines use the DC motor.
T-Man

I made a mistake, I mixed up the two different types. You are correct! 3-rail is DC while two rail is AC. :laugh:

PW
 

· Yard Master & Research
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O OK Technical. A DC motor needs DC and an AC motor needs AC or DC. With an AC transformer you can convert to DC with a do hickey called a bridge rectifier. The DC transformer you do not need to convert but give up all hope of operating a post war whistle because it activates on DC. It will run constantly under DC power. Hows that!
 

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O OK Technical. A DC motor needs DC and an AC motor needs AC or DC. With an AC transformer you can convert to DC with a do hickey called a bridge rectifier. The DC transformer you do not need to convert but give up all hope of operating a post war whistle because it activates on DC. It will run constantly under DC power. Hows that!
Sounds Good! :thumbsup: :smilie_daumenpos:
 

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OK T-Man, etc.

Here's a techy "powering" question for you...

I just bought a new Lionel CW-80 AC transformer on ebay. Before I hooked it up to the track, I touched my multimeter to the output terminals ... the multimeter was set to AC volts. To my surprise, the multimeter was showing something like 19 volts AC regardless of whether I had the transformer throttle off, midway, or full power.

At first, I figured my CW-80 was a lemon ... not functioning right.

But, I went ahead anyway and wired it up to the track, and tried to run an old loco (my 249). Sure enough, the loco runs just fine, and the CW-80 gives me reasonable throttle control. As I vary the throttle (with the loco on the track), the multimeter voltage ranges from around 8 to 16 volts.

So, I'M STUMPED ... why does the multimeter show 19 V AC coming out of the CW-80 transformer when there's no train on the track, regardless of the throttle setting???

Seems counterintuitive to me ...

TJ
 

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TJ,

I'm no electronics expert, but is it possible you're inadvertently running off your accessory current? If you've managed to cross your wires and have your hot line for the accessories connecting to your track, I think it would give you constant voltage with the transformer in the "0 mph" position. If you want to test that theory, disconnect the accessory leads from the transformer and see if your power goes away.
 

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Hey Reckers,

Good thinking ... but that's not it. I'm wired to the proper transformer terminal (on a simple oval track), with no accessories hooked up.

Maybe my understanding of what a transformer does is "old school" ... Ohm's law, and all that ... two separate wire coils, common iron core, transfer of power, reduction of voltage. Certainly, with an "old school" transformer, the output voltage varies as you dial the throttle (rheostat).

But with this "new school" stuff, I'm wondering if there's some internal circuitry that somehow senses the load demand, and then adjusts output power (voltage, current) accordingly???

I've pinged my question to the "contact us" section of the Lionel website. Not sure if I'll get an answer any time soon. I'll post it here, if I do.

Again, the train runs OK ... it's just that it's ME who's stumped !!!

Maybe I (!!!) need some fixing !!!

TJ
 

· Railroad Tycoon
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Okay----I don't know the solution, but I have something for you to read. This is the manual for your tranny: http://www.lionel.com/media/servicedocuments/71-4198-251.pdf

On page 7, it talks about internal circuitry that varies the output all by itself as you start up or slow down. Hope it helps.

I don't think you can adjust the volts on the 80 watt.

Though when I got my 80 watts (2 of them) the advertisement said adjustable voltage.
I asked how to adjust the voltage and got no reply. (2 sellers on e bay) I guess they didn't know either.:rolleyes:
Got one for $20.00 and the other for $30.00. When I got them Lionel was selling them for over a hundred!
So I just assumed it adjusted with the throttle lever. I never put a meter on it.
And now I got my ZW and use that for power and the two 80 watts are for accessories.I know on the ZW's you can as there's a separate dial to set the voltage.

I did read something about a bunch of bad 80 watts transformers sold. Something about the way they built them. A wire was switched or something. it was an easy fix though.

You got to watch because they sell a 30 watt (or 40?) that looks just like the 80 watt too.
If you find the answer let us know.
 

· Yard Master & Research
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My cheep little tyco reads 20 volts That is only the potential difference not the real output. You need something running on the track to get the right reading. So by adding resistance the voltge will drop.

What I am saying if it works run with it. If i could explain the reason it wouldn't make any difference.

The CW 80 does have an adjustable output voltage for accessories.
 

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Re: Transformer voltage ...

That is only the potential difference not the real output. You need something running on the track to get the right reading. So by adding resistance the voltge will drop.
I think T-Man has it right when he refers to the "potential difference". It's been a long time since I cracked open my old EE books, but I suspect "adding a resistance" for a voltage drop is the correct rationale.

Thanks, T-Man!

I downloaded the CW-80 manual from Lionel today. Same link, Reckers ... thanks! (My ebay buy didn't come with a manual.)

From what the manual says, the CW-80 DOES have a user-defined variable voltage LIMIT on the accessory side. One has to go through a proceedure of holding down the DIRECTION / WHISTLE / BELL buttons at the same time, then moving the throttle to get the desired accessory output voltage, then releasing the buttons, etc. Sort of a "twister" back door programming procedure.

I don't have any accessories hooked up, so for me, it's a moot point.

Anyway, my CW-80 seems to drive the train OK. So, T-Man's "if it works, don't fix it" philosophy likely wins the day.

But, still ... I wish I had paid more attention back in my old EE classes...:)
 

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Re: Transformer voltage ...



I think T-Man has it right when he refers to the "potential difference". It's been a long time since I cracked open my old EE books, but I suspect "adding a resistance" for a voltage drop is the correct rationale.

Thanks, T-Man!





I downloaded the CW-80 manual from Lionel today. Same link, Reckers ... thanks! (My ebay buy didn't come with a manual.)

From what the manual says, the CW-80 DOES have a user-defined variable voltage LIMIT on the accessory side. One has to go through a proceedure of holding down the DIRECTION / WHISTLE / BELL buttons at the same time, then moving the throttle to get the desired accessory output voltage, then releasing the buttons, etc. Sort of a "twister" back door programming procedure.

I don't have any accessories hooked up, so for me, it's a moot point.

Anyway, my CW-80 seems to drive the train OK. So, T-Man's "if it works, don't fix it" philosophy likely wins the day.

But, still ... I wish I had paid more attention back in my old EE classes...:)



So that's how it works.:thumbsup:
I didn't get any manuals with mine.
Thanks

The ZW.....you can dial how many volts you want to get to the rails.
 

· Yard Master & Research
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In working with trains I find I need an understanding but I have limits with theory. The conversations just get too technical That it makes no practical difference. That is where my line is. I just like to know what I can do that works.
 

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Hi guys,

Re: CW-80 "no train" voltage (referenced above) ...

A tech rep at Lionel responded to my question (rather quickly, I'll say ... in less than 24 hours I had a response ... excellent customer service there!). He said:

"Yes, there isn't an internal load on the CW 80 transformer like there would be on an older transformer, so you will get inaccurate readings when powering up the transformer if it isn't connected to anything."

So, straight from the horse's mouth ...

Thanks, gents!

TJ
 
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