Wiring crossovers in February CTT

[lionelsoni]

I found the article "Wiring for double crossovers" on page 82 to be rather confusing.  For example, the section "One-throttle operation or command control" refers to figure 1, which shows middle-rail gaps and two tracks powered from the A and D terminals of a ZW transformer.

However, as some of you may guess, my main complaint about it is that it is advising how to wire the crossover to allow crossing from one output to another of the ZW.  This is unsafe, since any difference in those outputs' voltages, whether deliberate or accidental, will cause a fault condition:  Current can flow across the rail gap through the locomotive or lighted-car pickups from one center rail to the other, bypassing the transformer's circuit breaker, which will therefore not trip due to overcurrent, no matter how great.

This situation is a fire danger when a train stalls over the gap.  But, even when the train gets across, as it usually will, the sudden connection and disconnection of the rails can cause voltage spikes of hundreds of volts, endangering modern electronics-intensive rolling stock.

The wiring of the crossover itself is not dangerous, and it would not be any different in a proper block-control system.  The problem is in not having the electrical switches needed to connect both blocks (the two main line tracks) to a single transformer output when running across from one track to the other. 

[JTrains]

I thought the same thing when reading the article - just hadn't found the time to post something here.  It appears that there is a divide about whether this is significant concern or not, at least in normal operation.  At a minimum, I think the article could have made the reader aware of the possible risks.