I have been out of the loop for awhile. Recently purchased new ZW for my uncle who has had several of the original ZW’s. He informed that he could not use the current ZW with his current setup of 20 years. He states that he would have to replace all of his old track, etc… Is this in fact true? If so what type of changes must be made? Thanks, Raildoc
Raildoc -
A little confusing, can you elaborate? Was their a specific reason for the new ZW? Did you get any power bricks? Assuming his 20 year setup is tubular or Lionel track, correct? Do you have any idea of what type of trains he is using? Assuming Lionel type O scale. Not HO or something else correct.
On the surface the new ZW would work, but there must be more to cause his comment?
No, on both counts.
To my knowledge, the new ZW can opperate as a traditonal transformer such as the old ZWs and a power supply for TMCS. I see no reason that this controler couldn’t be wired in (even phased in) with old ZWs.
I run my two new ZWs with both old and new track. No problems.
laz57
I was running a 681 with six Madison style passenger cars, bulbs wired in series, last night. Pickup rollers badly worn which I think contributed to the overload circuit cutting power with a new ZW. Need to find another PW loco and see if I still have the same problem.
Mel Hazen; Jax, FL
Don,
Old ZW’s tended to short out excessively requiring them to be rebuilt. Family just wanted get him brand new transformers since he is in relatively isolated rural area, also he is older now and in need of trouble free operation:). O27, likely Lionel track and 2 bricks purchased with transformer. How is the wiring different, what else has to be done?Thanks,
Raildoc
I have old 027 track Marx & Lionel from the 50’s and the new ZW works just fine. No problems. Wiring is the same.
It’s probably not track but the way he’s using his old ZW’s. The old ZW is a variable transformer It puts out a more or less pure sine wave with amplitude varying by the roller tap on a winding. The new ZW is an electronic chopper type circuit. Basicly you can think of power supplied as the area under the sine wave and it cuts the voltage to zero at some point on a max curve to adjust power.
Under certain conditions using both transformers together you can get cross currents between the two. This could most likely happen in layouts with common ground and insulated loops bridged by a crossing engine and at times between Postwar Switches powered by different transformers. These cross currents would only flow at points in the AC cycle where the max peak voltage of the two transformers is different. If you use a meter to measure it may appear the voltages are equal. Hook them to a dual channel oscilloscope and you’ll see the problem.
Therefore, it is best to either use the old only or the new ZW only in a layout. I believe his old ZW is fried again anyway. Any literature or sites that specifically address the operation and specs of the new ZW?
If money is not an issue then all new ZW’s are the safest and most convenient way to go. Add a TMCC controller and you will have remote control operation of your old PW engines. I think Lionel has a copy of the new ZW manual on their website.
At the risk of giving you too much information…here are some links from the FAQ index.
What transformer to use?
http://www.trains.com/TRC/CS/forums/1022084/ShowPost.aspx
ZW-Old vs. New
| Lionel Fastrack Setup |
|---|
Should I purchase a new or old ZW? How can I run conventional locomotives remotely using new ZW? Should I update conventional engines to command control?
http://www.trains.com/TRC/CS/forums/1022598/ShowPost.aspx#1022598
http://www.trains.com/TRC/CS/forums/1034084/ShowPost.aspx
How do I run conventional engines with DCS?
Pat, it reads like you are describing a phase-control circuit, like that used in the CW80. Have you actually looked at the waveform? I have never had a new ZW to examine; but I imagined that it was something more sophisticated, like chopping, since there seem to be relatively few complaints about it compared to the CW80.
Pat, it reads like you are describing a phase-control circuit, like that used in the CW80. Have you actually looked at the waveform? I have never had a new ZW to examine; but I imagined that it was something more sophisticated, like chopping.
There are two ways to generate AC power without the variable transformer. One is essentially a low frequency amplifier giving you a near sine wave. The other is chopping a fixed AC wave. Again power is area under the curve. Chop it once on the half cycle and you have the CW-80 or mix AC and modulated pulse width for the more sophisticated version. Both are syncronized to input AC. Both lead to small but measurable instances of voltage variation on the hot side of the line between the two outputs
One of the problems with O-Gauge is the lack of Universal Standards, Company A can produce items that work with all it’s other products but not those of Company B. I’ve used postwar ZW’s forever and never had one fry or burn out. Yet this poster describes burnout as almost routine. The only service I’ve done on my ZW’s or KW’s is relace the carbon rollers. There has to be a reason for his problems and without more information about his track or operation the most likely cause would be mixing the new technology with the old.
It sounds more like some of his PW trains are in need of serious maintenance. If he has a bunch of open frame motors that need replacement brushes and/or work on main bearings these could be leading to excessive current draw and tripping of the modern ZW’s breaker and possibly problems with his PW units older style thermal breakers. I seriously doubt he is frying the transformer cores.
Most likely he has issues with the breakers in the ZW’s giving him touble. I also can’t think of any scenario that would be helped/fixed by replacing the track?
I understand chopping and phase control (which can be thought of as a special case of chopping). I’m just curious to know which is actually used on the modern ZW and thought you might have seen the waveform, from your comment about the oscilloscope.
By the way, the power (into a resistive load) is not proportional to the area under the waveform (which is zero over a full cycle), but to the area under the square of the waveform. The (root-mean-square) voltage is proportional to the square-root of that.