New ZW-L Inaccurate??

put a load on it yet? Recently there was a thread talking about transformers needing a load to output accurately .

I noticed that descripency but I expected it. 

I'm not sure a multimeter will measure the ZW-L's "voltage" accurately.  Apparently Lionel is chopping 18-volt sine wave power with different duty cycles to get variabls amounts of power going to the track as you vary the throttle, perhaps along the lines that Mike Reagan I would not expect a a normal multimeter, perhaps with some different scheme: whatever they are doing sure works better than a CW-80 thoughy, that is certain. 

Regardless, I doubt a simple, sub-$500 multi-meter, not designed to accuratley trap and measure the energy in all harmonics, and not just the 60-cycle range,  to read pure 60-cycle sine wave power accurately, to necessarily read this outputs "voltage" or power content correctly. 

I'm very pleased with mine.  The indicators on the thottles, and the meters, do show the relative amount of power going to the track and seem to be clabrated so they are pretty linear (level 16 seems to give twice the power of level 8, etc).  So, I think of these as power levels that roughly correspond to voltage but not necessarily. 

The ZW-L strikes me as a superb unit, and I could not be more pleased with mine,  

I wondered if it would read true rms voltage or current. Seems like using analog meters, there's a better chance that it would. Was the meter that was used to check it true rms reading?

However, as a relative reading it should be useful in any case.

This might have come from the fact that a high impedance meter ( most digitals) will read a voltage even when a triac controlled output is zero. A load allows the tiny current leakage to be "shorted out" so that the meter won't record it erroneously. 

SandJam - forgetting for a moment the voltage measurement,  how does your ZW-L run your trains? 

The voltage meters on the ZW L indicate RMS voltage.

The markings on the handles are something left over

from the orginal ZW and are not calibrated.

I'm using a 400.00 Fluke meter, it's pretty accurate any other time I've used it.  The output from the transformer doesn't worry me.  It's got plenty of power.  It's just annoying the meters don't match the handle designations  or that you can't use the handles or meters to actually set a voltage.   Obviously all the extras contributed to the high cost.  I was hoping they'd be accurate.  I'm going to use a second zw-l to power switches, accessories, lighting, basically all other things except track.  i have a ton of operating accessories.  Each operates at different voltages to make them run perfect.  I was hoping I could quickly set the output using the gauges anytime I want to run a specific accessory.  

My KW transformer is right on.  Set handle to 12 volts and Meter reads 12.2.  

I guess I won't have to worry about setting the volts to high for my legacy engines since the max volts of 20 on the meters only ever outputs around 18 volts.  

PowerHouse's only put out 18v, I imagine they did the same with the ZW-L

i would of thought they would have calibrated them to match the meters for a list price of 800.00.  I mean the handles are not the same size as the postwar zw, they are much bigger so its not like they used the same spec as a postwar zw handle.   

Interesting discussion.  I have to agree with SandJam, it seems that the markings could have been more closely calibrated for the price of the unit.  Seems like it would be easy to do when the design was being readied for production.    Perhaps just an oversight at Lionel, it probably did not occur to anyone working the development to check on the alignment.  Still, its a very cool device.

I wonder if there is a series of calibration pots inside...too much to hope for. Of course this would not help the mechanical scale.

Gentlemen,

   Nasty old KW's the nerve of those old Americans to build a transformer that delivered 16 Volts when the handle was actually set on 16.  Yep got two of them that

still do it after 40 years.  Where did you say that ZW-L was built?

PCRR/Dave

Nast old KW

I really don't see why anyone is concerned.  As I said, I wouldn't trust a multimeter to read it right.  But I never assumed the calibrations on the throttle, or the readings on the meter, were accurate voltage because it just does not matter.  Personally I would suspect that if something involved in your test is wrong, it is your meter, not the ZW-L.  But that really is irrelevant. 

What is important is that the throttle calibrations and meter readings will be consistent.  For example, I have established that my Southern Crescent runs at the speed I like to set it cruising at an indicated 11.5 on the throttle, my shifter at 10, my ATSF ABBA set with seven cars at 15, etc., my MTH 241.A at 12.5.  Those voltages give the speeds and performance I like.    I've written that down on my run sheet, and I am confident when I run them next - tomorrow or next week, when I set the throttles to 11.5, 10, and 15 and 12.5, I will get that same speed with each loco, etc.  That is what is important.  I bought it to run trains and it does it splendidly. 

Lee,

 Sean makes a good point,  if the old KW was made correctly why not the seriously expensive new technology also.

PCRR/Dave 

Hello guys and gals...

Does the MTH Z4000 do that too? 

The woman who loves the S.F. 5011

Tiffany

Admittedly, electronics is not my forte', however, based on my limited running with the ZW-L I have been very pleased.  It not only provides enough power to operate my entire railroad, but my command locomotives have really responded well to it giving me what I perceive as better performance.  Bo 

Visit my website Bo's Trains at http://www.bostrains.com

The PWC ZW does this too. The dials are there to give the appearance of the genuine article, but the actual voltage is anywhere. It is also non-linear. For my PWC ZW, 12 (dial) is 12, 18 (dial) is actually around 15, and 20 (dial) is 18. It drives me nuts. I had high hopes for this new ZW-L, but now I am not so sure. I also can not abide the "off" delay the PWC ZW exhibits.

Mine does.  My Z4000, Tech III, and ZW-L all give readings that do not correspond 1 to 1 with a multi-meter voltage measurement .  All three use a type of voltage chopping/non-linearly synthesized output.  So I never expected the Z4K and ZW to "measure accuracyly" on an AC multimeter scale, or the Tech III on a DC -- and they don't.  That is not the fault of the units, nor in my opinion of the voltage measurement device.

People may have noticed that the "inaccuracy" in voltage measurement, mismatch, whatever-you-call-it diminishes as one gets near the maximum output, just as one would expect (the chopping diappears as one gets to full output and thus the harmonics content that causes poor RMS reading in low-cost voltage measurement units is reduced to near zero): I get roughly the same "inaccuracies" reported at the top of this thread in the 11-14 volt range (read my review and note I report trains run at lower indicated voltage) but at maximum, I get almost exact agreement.

Meaning no offense, but I will stick with my point that this is a tempest in a teapot. It just does not matter when running trains. We are dealing at both ends - in the loco and in the power supply, with non-linear devices.  The manufacturers of both the Z4000 and ZW-L have given some markings on the throttle as a guide to consistency in setting the throttle, as I explained above, and meters that may or may not measure RMS or may have adjustment circuit to try to mitigate effects of the non-linearity, but neither is perfectly 1:1 in correspondence with what a multi-meter would measure but that doesn't mean they are wrong, or the multi-meter (they are just measuring different things). 

Where I have myZW-L mounted the benchtop completely blocks the view of the meters unless I bend down to look directly under it.  The meters on both the MTh and Lionel units work for me mainly as a diagnosis of short circuits, etc. - I will note than on both Z4000 and ZW-L, the current meter is accurate at the one point where it really should be: both units indicate right at 10 amps just before thir 10-amp breakesr opens. Now that is useful. In the six years I used the Z4000, while I found the meters interesting and useful because they are consistent to the unit for setting trains at levels I have written down, I have only depended on the absolute accuracy of the meters once, and that was the current meter only, when setting the unit to stay at 9.9 amps at an indicated 2 volts so I could feed a fault and find it due to overheating of the track. 

Funny how we keep excepting less for more and make excuses for it. OMHO

quote:

I wondered if it would read true rms voltage or current. Seems like using analog meters, there's a better chance that it would.

I have read that there are circumstances where analog meters are more reliable / accurate than digitial meters. There are plenty of folks that seem to want Simpson 260 VOMs and other analog meters of similar quaility. They are still being made. Amazon has them listed at $249.00.
Perhaps this is one of those cases.

But Officer, the speedometer said 65.

Gerry

   In my experience, the Z-4000 does not exhibit this behavior. When mine says 8V, I have 8V to the track. When it displays 14V,  I get 14V, etc. My PWC ZW does not have this action. The voltage clearly jumps from 14V to 18V more quickly than it does from 0V to 14V and this is not reflected on the dial markings.

   Taking the meter out of the discussion, I consistantly have a very hard time operating locomotives conventionally with my PWC ZW. The voltage delivered is either too little or too much, it is very hard, if not impossible to find a setting that works well. For example, my 746 operates nicely on 13V (displayed) from the Z-4000, but the same performance is attained just above the 16V mark on my PWC ZW. Moving the lever slightly forward causes it to rocket, and setting just below the 16V mark causes it to stall. This rapid voltage change can also be seen in the headlight and any passenger cars.

I have found my Z4K's to display the same voltage on it's meters within +/- .1 as what it is actually putting out as measured with my top of the line Fluke meter which I have found to be highly accurate over the years.

Maybe it has something to do with the Licensed professional engineer's Simple Green pollution that his meters doesn't measure the same.

The MTH Z-4000 digital readout is darn near right on. I have to agree with Sandjam, why install meters if they give an inaccurate reading, especially for the big bucks.

I thought the Z-4000 had a pure sine wave output.

Or does it have a chopped/non-linearly synthesized voltage output?.

Well, this discussion isn't going anywhere.  I bought the ZW-L to run trains, and it does that well.  In fact, it is the best unit I have ever seen to run O gauge trains conventionally, far superior to any other unit (including the old ZWs, etc) in making trains run  slowly, smoothly, with a very linear and granular response to the throttle, and so they respond consistently to the direction button. 

I sense an opportunity here . . .  I would really like to have another ZW-L.  So, anyone within driving distance of me who is uphappy with their ZW-L, I'll trade you a perfectly good, working Z4000 and $200 cash: I'll drive to you or you to me with the unit, we'll check the units both work fully (voltage accuracy aside), swap them, and you get $200.  If that works for you and you are within two hours of central NC (Raleigh-Cary), e-mail me!

Lee

This post probably belongs on the FOR SALE or TRADE Forum

So whos gonna be the first to contact Lionel regarding this issue?.............. 

I posted it there, but its really here because I'm putting my money where my mouth is and wondering if others will, too.

I imagine they have seen this thread by now.  Earlier this morning I e-mailed Allan Miller and suggested an OGR investigative/educational article about power supplies, "pure" sine waves and chopped & synthesized voltage outputs and why some work so much better than others for some tasks, and how the various old and modern supplies work.  I'm not sure who he would get to write it - I made it clear I would not touch it - too much work and probably controversy and I've written whole chapters about harmonics and power measurement and I'm sick of it.  But I hope OGR does it.

Ladies & Gentlemen,

   My Z4K  is right on the money says what it delivers to the tracks.

This is not to say I would not purchase a new ZW-L.  However for the purchase price it should be engineered correctly.

PCRR/Dave

The answer here is simple,,,,,,,,,,,,"Return to where you bought it, and ask for your money back.

I have never run my trains on dials, since my 180 bricks showed 17 volts, returned them , got 2 more, and they showed 19.5,,,,,,,,,go figure. i kept them and hooked them to "400 by IC CONTROLS', everything fine since.

Rod

I think this would be a great article if written by someone like Dale M. I imagine he has more to do with his time, but some of his posts on this very subject (not so much the accurate metering, but the nature of the waveforms) have been enlightening and in my estimation right on the money as they say.

As to the Z4, I believe that waveform is a sine wave that is made up of segments rather than a chopped off sine wave. I would guess that it is easier to read accurately by most meters, true RMS or not.

In addition, when the whistle is activated on the Z4, the amplitude of the positive half cycle goes up about one volt, but the negative half remains the same. And as well pushing the bell causes the negative half cycle to go greater negative about one volt and the positive half sine says the same. This is how the DC offset is accomplished to activate the whistle or the bell. BTW the somewhat perfect sinewave from the Z4 does have a tiny glitch at the zero crossing which is no issue whatsoever. So any digital meter true rms or not, analog, or whatever will read true AC voltage from a Z4.

Don't get me wrong.  This transformer runs trains great.   And no I'm not selling it, hahah.  I love the 3 levels of power protection, I love the 4 individual breakers.  The output works fine.  But my main point is that after how many years waiting for this unit and the high price I think the calibration could have been better. I mean this was a brand new design.  Otherwise save us the money and lower the price instead of putting on a feature that doesn't work correctly.  It's still a great transformer.  But if the meters/handles were calibrated right (or at least close) it would have been an incredible transformer.  Oh, and yes I'm still getting 2 to run my entire layout and dumping all the bricks and individual tramsformers I have now to power all the other stuff. Just another little item to learn to live with, thats all.

Thanks

At the Hamburg, PA train show yesterday these beauties were going for $616-$625.

HAHA Lee I like you, you are so funny.   You are the guy who is usually so picky about his Lionel stuff.  I see your posts all the time.  You are always modifying something.  I just saw you tore apart your brand new Blue Comet passengers cars because you didn't like the window color, haha.

Have you already torn apart your ZW-L and made it work right!   Just kidding.

I'm not seeling my ZW-L its a great transformer.  But just pointing out we expect a lot for our money.  And I think the calibration could have been easily done on Lionels part.

Another thing that Lionel pointed out in their video on the subject was that the shark tooth waveform provides a rather high peak voltage when the average or RMS voltage is set somewhat low when running an engine in conventional mode. What this does is provide the smoke unit, which in the newer engines apparently stores the high peak voltage in a capacitance, a higher voltage to produce more smoke. Their video shows a conventional running engine using both types of transformer outputs and the result is pretty dramatic.

The topic title needs to be followed by a question mark (?) since the posting individual is only relating one person's experience with one example of the product.  His findings may or may not be valid or accurate.

Hopefully Jon will see this and chime in, the ZW is his baby and I am sure he can tell us what is to be expected