MTH PS-3 steam engine and postwar ZW transformer

It should be able to operate conventionally under a postwar ZW. 

Does the engine have to be set by the DCS controller to recognize conventional operation with the ZW?

No.  It should come up in conventional because there is no TIU to send it the "watchdog" signal that tells it to come up in DCS mode.  I'm really not the one to help on this topic, since I don't run MTH locos in conventional mode.

I am aware that sometimes you have to hold the direction button, or cut power, for a few seconds to get a reaction.  A quick cut won't do it.  Try holding the direction lever on the ZW for varying durations of power off.

Yes I have already tried that, just do not know if the problem is the ZW or in the engine.

 What does the manual say for a conventional reset . Never mind you don't have a bell button with the ZW.

However there is way with the dcs remote.   Set up  a var channel to var mode.

turn off the dcs signal  to that channel . scroll the voltage up to around 10 volts and try the conventional reset  using the dcs remotes whistle and bell button  combination.  

You need to do a conventional reset.  Maybe locked in neutral for conventional.   G

GGG,

I dug out the z-500 from an old set and reset the engine in conventional mode with the bell and whistle buttons. This unlocked the engine and it ran fine in conventional. Out of curiosity I ran it in command mode and then tried conventional, it locked up and had to be reset again. This makes going from the main layout to the Christmas tree a little frustrating. Any idea why it has to be reset to run in conventional after it has been run in command?

No I don't, interesting.   G