PSX1-AC needed? for Lionel ZW-L

I personally I don’t think you need it you can sure add it won’t hurt but I think the breakers in the ZW-L are very quick. Definitely quicker than a Z-4000 😜

...and you can set the amperage that you want it to trip.

You can not do that with the ZW-L so if you want that option by all means add the PSX1-AC. Like I said I doubt there’s anything wrong with adding it or not adding it. I’d actually be interested in a test to see how the ZW-L breakers or the Legacy PM do against the PSX. Wouldn’t be surprised if the PSX beats them but I’d bet they aren’t far behind

It’s important to understand the difference between a “circuit breaker” such as the PSX, and the design of the ZW-L for handling shorts/overloads.  The ZW-L has four 12Amp circuit breakers, but uses three methods of power handling of the available 620 watts. Quickly, the first(dynamic power limiting) spreads power across the in use channels to a maximum of 180 per channel.  More details apply, but not relevant to this discussion.  Second, on a short or severe overload detection, the ZW-L “folds back power” and holds at 10amps on that output leaving the other channels alone.  This occurs for 3 seconds. The red light blinks indicating a problem.  If the short or overload is not corrected, power is interrupted to that output.  The red light is on solid and the meter for that output goes dark, indicating to the operator which output is involved.  The 12amp circuit breaker is a fail-safe for electronic over current protection, and because of the “fold back” design will trip infrequently, as the problem has been addressed and resolved during fold back procedure.  Page 5 in the ZW-L manual explains this design and operation in detail.

Edit:  I don’t have a dog in this fight.  Discussion purposes only about the difference in handling circuit breaker protection.  You make your own decisions on what you prefer.

@Windy City posted:

Is a PSX1-AC needed when using a Lionel ZW-L?

my two cents, yes.

So there is a short with 10 amps going through it for 3 seconds?  Is that good?

I think I prefer a PH180 or PSX type protection where the short lasts only a nanosecond.

Just a reminder, circuit breakers protect the transformer, not the load. If a ZW-L is "limited" to ten amps for three seconds its because it desgned to handle that much current for that long. Most all the electronics inside the engine will not tolerate 10 amps and if there is a short there they will be up in smoke long before the circuit breaker trips. Thats why you need a TVS between the transformer and the load.

Pete