IBM 610 workstation computer 3383

Oh yeah. But it's 'only' 277 volts. I suspect the idiots who came up with this idea were more send in electric traction than building systems. On electric RRs, the loads can start low, build to brutal numbers, then dissapear just as fast. I was watching at Long Branch last friday, on a 25kv system (single phase, BTW. Yes, they unevenly load the utility) as a train left. Catenary currents started at 10 amps (at 25kv) and quickly rose up to 200 amps, then dropped almost instantly as the train coasted, stopped at a station, and grabbed more pbuttengers. The load then shot up AGAIN to around 180 amps and started to fluctuate from wheel slip and other things, going rapidly (i.e., in the space of a second) from 180 or so amps, down to 140, then back up. At 25kv.

This is normal operation on such a system.

I suspect in the fan plant application, they won't care because these things start up 'during an emergency only'. Oddly, right at the on site sub (13kv to 480 and other voltages), you can see the 277 line drop a good 20 volts during startup.

In any case, i give them a few years and they'll end up changing the MCCs out to a better type of starter, if only because of regular testing causing THAT much damage to things - already one MCC blew up, and the fans themselvs are not exactly 'in spec'...

A lot of places now would use a soft start or VFD. Even smoother and friendlier to the power lines, and can be programed to skip speeds where bad vibrations occur.

One place I heard about an ALS start being replaced with a soft start, they had a few centrifuges, belt drive. Mbuttive things with 10 belts or so between the motor and drum. They would pop belts regularly, and of course once one popped, the others popped even faster. Plus, the stuff being spun sometimes got down there, or grease, or something. Slipping belt and smoke and fire.

After finally convincing them to install a soft start, they went from regular fires and popped belts to no fires and belt lifetimes in the year range or better....

Oh, true.

Oh but pumps are on-off :)

Plus the instant gratification thing. And overprotective parents...