Most Historic/Unique/Messed-Up/Butchered
The Detroit-Windsor Tunnel - (On the U.S.A side) This was originally a 4.6-kV, ungrounded, two-source primary, breaker-and-a-half?, three-bus, secondary selective system, which was also fed by two additional incoming alternate source feeders supplied by the Canadian (Windsor) side routed under the Detroit River (via an international highway tunnel). On the Canadian side, an identical power system existed - also with two alternate source feeders fed from the Detroit, MI side, except that on the Canadian side, the primary system was originally 4-kV, ungrounded (very strange). The total number of sources is four, with two serving utilities involved, one located in Detroit, MI and the other located in Windsor, Ontario, but cross-tied for redundancy by four feeders - two incoming and two outgoing. To add another layer, the secondary distribution system also utilized an auxiliary bus which fed six singe-ended, primary-selective unit-substations.
In the beginning, the switchgear was all open, exposed live-front equipment with knife switches...
View attachment 2557484
Throughout the years, people have came and gone, upgraded/replaced equipment, retrofitted devices, etc. so now its a beat-up 4.8-kV, low-resistance grounded converted, two-source primary, two-bus, secondary selective system (on both Detroit and Windsor sides). The secondary distribution system now has double-ended secondary-selective unit-substations. My involvement at this site was to provide support to the field-services team, who failed miserably to integrate new protective relays and translate settings as part of a service contract. In the process of executing our main scope of work, I began to notice odd things, and started to look beyond our portion of the work. I discovered how messed-up and mis-applied the culmination of all the "so-called" upgrades over the years were. I saw remnants of the ungrounded system, inadequate ground-fault detection, misapplied devices and protection settings, emergency source deficiencies, hacked-together automatic throw-over logic, overall lack of documentation, etc...