Ok so this one is long winded, but I thought it needed to get out there. Working today on 2 simplex elevators, shared machine room. Electricians were in there just ahead of me doing some touch up work, as this was my third day on the job and I had already started a small punch list for them. Turned my assistant loose on car 1 and was beginning some adjustments on car 2 to get it to run on inspection. Turned my three phase disconnect off, so I could begin detailing the controller and verifying all motor leads and incoming three phase power leads were tight to the starter. Just after turning off the three phase I turned around to work, when a green indicator coming off the three phase disco caught my eye, funny its turned off, why is the indicator light on.... Jiggled the handle to make sure it was fully down, damnit, where is that meter at now, checked the legs, holy Crap 480VAC on 2 legs....
After the deep breath, man that was close, thank you gods, I began my investigation. The disconnect is the type with internal transformers to create its own shunt trip 110VAC power. The electricians thought it a great idea to connect the two controllers, connected equals single source right? The step down transformer was now being back fed, form the still powered up car 1, and turning it into a step up transformer the other way, for the two legs. The luck of the draw, these were not the same two legs my controller used for its own transformer so, no LED readout on the soft starter, no indicator lights on the boards, just blank friendly pieces of elevator controller inviting me to touch them.
Been in the trade 13 years now, the last 7 or so as an adjuster. Mostly Hydraulic elevators as I am just getting up to speed on our tractions. I adjust or inspect roughly 5-7 cars a week, and have worked with these types of disconnects at least 200 times. I am, and forever will be, learning. Posted this so everyone can maybe take an extra 30 seconds to be safe. Glad to be around for another day, maybe the wife will even let me be the boss today!
