I ran my 12x32 5 track mountain cottage shelf operation as 5 power districts from 3 pw ZWs, (throttles: AUx3, DUx2) from '92 to '00/01 when replaced with 5 180 watt P0HOs . The Districts were monitored by 0-30 range VAC and 0-15 AAC 2% variation panel meters. On one district where I ran two,double-headed very long incandescent lighted passenger trains, occasionally after a time, the 10 amp rated fuses would blow at 10-11 amp load or, about 180-90 watts. I owned 5 pw ZWs over time and never saw one produce over 10-11 maximum amps under load. Current surges can change the railpower environment, but the published high wattage rating on the pw ZW is input not output.
On all the other mostly freight Districts they were fused with 7 amp and never blew unless a derailment occurred. Anyway, I quickly grew to favor the 180 watt PoHos with the comparatively quick acting breaker and fixed 18 VAC.
