Train blocks and multiple transformers

@Yank2304 posted:

- I have read a significant amount of material on this subject from this board and I have concluded NOT to run trains over two blocks via different transformers (a train switching from track 1 to track 2 both controlled by a different transformer.

Your conclusion actually should have been NOT to run trains over two blocks via different post on the same transformer (a train switching from track 1 to track 2) both controlled by posts on the same transformer(ZW, KW, Z, V, SW, R, eg.) as a serious damaging internal fault/short can occur when the two throttles are at different settings. While the same voltage potential can happen using different, phased transformers, the fault is external to the transformers and rarely causes damage.

Rich is correct.

Remember though that the throttles on the two transformers (each controlling a separate section of track) should be set to the same voltage before the train travels off of one and onto the other.  Otherwise:

1.) You'll get a significant speed change as the train crosses the boundary between the two;

  and

2.) You'll essentially have a short circuit between the hot terminals on the transformers as the train crosses because you'll likely have one locomotive pickup roller on the exiting track and the other one on the entering track at different voltages.  Not a problem if the tracks are set to the same voltage (throttle setting) and phased correctly, because in this case it's a very small and temporary short circuit.  However it's a much more significant problem as the difference in voltage (throttle settings) becomes bigger, even if they are phased correctly, in which case it's a large temporary short circuit.  You could trip a breaker, or even melt the wire between the pickup rollers.

Mike

Listen, this makes my life easier if this is the case.  How do I isolate the tracks between the transformers?  Just the hot or the hot and the common?

what about the two different sides of the z4000?

Yes, isolate just the center hot rails.  The whole key is to phase all the transformers .  When traversing between two blocks try to keep the two transformers voltages close to each other and all should be good.

My layout has three LW transformers, all phased and operate three main loops.  The whole layout can be run on one LW, or two LWs or three LWs and traverse between loops all the time with out issues.

Charlie