I've owned the ZW-L for over a month now and its one fine transformer. On my 16x13 layout, I have 2 main loops, plus sidings. It powers all my track plus all my switches. As others have reported, conventional engines do run better with it. I have an FM trainmaster than can really crawl now.
I did manage to bring the ZW-L to its knees unexpectedly. I was running 4 heavyweight lighted passenger cars pulled by a TMCC Pul-mor GG-1. To get the GG1 moving the amps read 6 on the gauge. The ZW-L starting flashing the red light indicating I was drawing too much power. But I am only at 6 amps. I should be able to go 10 amps before this happens. The only way to get the red light to stop flashing was to decrease the power to the track from full power (18 volts) down to 16 volts. Then the GG1 and its lighted cars ran perfectly.
I then tried to double head the GG1 with another TMCC GG1. The amp gauge was reading 9 amps but the ZW-L was handling it - BUT only at 16 volts. I could not bring the voltage up to 18 volts or the red light would flash.
I know the ZW-L can handle it but why not at full power? I then tried other TMCC Pul-mor engines I had. Same result. With the 4 lighted cars in tow, I ran 2 TMCC gp9s. At 18 volts to the track, the ZW-L would not let me pull more than 6 amps or the red light starts to flash. Decreasing the voltage to 16 volts and it runs perfectly.
This problem only occurs with pul-mor powered engines. I tested a can motor engine (TMCC K4). I had to put 12 passenger cars on the track and the smoke unit on on the K4 to get the amps over 6 on the gauge. (Those can motors are really efficient!) But the ZW-L worked perfectly at 18 volts to the track and I was pulling over 6 amps. I then double headed the K4 so I was pulling 7 amps. No problems. At full voltage to the track, it was handling the high amps (as I would expect).
For some reason at full voltage, I can not run a pul-mor powered engine if the amps go above 6. It will work fine if I decrease the voltage by one or two volts. Yet over 6 amps with a can motor engine at full volts and its fine.
I tested all 4 channels with the same result. To eliminate any possible wiring issues with my track, I setup a test track. The ZW-L, the legacy base, GG1 and the 4 cars. Same result.
I called Lionel and they thought my ZW-L was having a problem. They gave me another ZW-L and I sent my original to them for review. I get the same results with the new ZW-L. It appears to me that there is some quirk it has detecting the overload when a pul-mor engine is running. Any TMCC pul-mor causes this problem. I tried GP9s, Century Club S2 turbine, GG1, and K4 Torpedo.
The simple fix is just to decrease the voltage and all is good.
Has anyone else seen this?