The Power Switch seems to be the culprit.
The generators to the northeast supply power to the copper mine and the nearby loading station. Placing a pole connecting the furnaces to the grid causes the power switch to do nothing. Removing the same pole cuts power going to the station (which is still connected) but the furnaces and mine keep going (which should not have power). Power to the station is restored when the switch is toggled off and back on.
Connecting the furnaces and also bypassing the switch with a pole, then removing the pole connecting the furnaces cuts power to the furnaces as expected. Then removing the pole bypassing the switch and reconnecting the furnaces restores power as expected. But when removing the pole cutting power to the furnaces instead cuts the power to the station until the switch is toggled.
P.S. Don't mind the biters. They won't bite.
