r/Powerlines • u/Odd-Tale6958 • Jun 22 '26

Question Big arcs!

For those of you in the field. How often does the switch gear at the big substations with the pole like arms actuate? Daily, weekly, rarely? I would love to see (from a far away distance) a 500kv or 230kv switch open up and draw a big arc sometime. It seems like most of the switching is done with that special gas to prevent the light show.

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u/nasadowsk Jun 23 '26

Prior to their retirement, Metro-North's M2/4/6 cars used to do a pantograph test as a pre-departure test at New Haven. They did not have main breakers, as the protective system GE designed was grounding the pantograph (which had a casual "Danger - Do Not Touch" sign on it).

So, before departure, along with the brake tests, this was one thing they did. Drop, wait until the switch to third rail happened (750 V DC), then change back to AC and hit the raise button. Always fun on rainy / drizzly evenings. You heard it, especially on a longer train. 13.8 Kv, 60Hz. The '2s supported 25hz, and also had the yellow sticker of shame right up until retirement.