When your pw ZW get hot it loses efficiency but as long as it doesn't trip a good, reliable breaker you are okay. That is why most everyone recommends a reliable external breaker or fuses to replace the old internal original equipment breaker on the pw ZW.
A cooling fan on the newer Z-4k reduces the heat problem applicable to the pw ZW. I have read of O-gaugers ventilating the pw ZWs case and blowing air over it with a small fan but have never seen one so modified and equipped.
A regards frequency of track connections you can measure for voltage drop under load[both with all train consists running and clear of trains]with a portable meter by comparing the reading at the transformer post to that of the distant location. Also, check to see if your long trains are slowing at the far distant point. I have always used permanently mounted analog AC amp and volt panel meters[fuzzy photos] to monitor at a glance the voltage and amperage load for each of the power districts.The panel meters can be an indicator of some problems but you still have to trouble shoot and find it. A portable meter is very useful for trouble shooting.
As indicated in an earlier post, I have operated "super powered" districts by paralleling fixed voltage Power House transformers, both 135 watt and 180 watt. But today I have no need for more that 180 amps per district.
If you use a test track to short and test the effect of a derailment on, for example, a pair of paralleled 180 watt transformers[20 amps] you will quickly learn that you have achieved scale welding capability. I used a pair of 135 watt effectively and safely, equipped with a magnetic circuit breaker. I can see where some Clubs with very long trackage might desire that kind of power or even 20 amps for very long, multiple trains as opposed to utilizing blocks.
