by F-line to Dudley via Park
Greg Moore wrote:It seems to me that ultimately it would almost make more sense to bit the bullet and move as much to one standard on the NEC as possible. It seems it would simplify the locomotive side quite a bit if for example we did move to one frequency.Frequency AND voltage don't need to be done in a monolith. Amtrak was clearly biting off more than they could chew in the 80's-90's studies about whole-hog 60 Hz/25 kV conversion. Frequency change from 25 Hz to 60 Hz at same 12.5 kV was done low-key and without service disruption on the New Haven Line in 1984 by Metro North over a series of weekends because all it involved was: state-of-repair catch-up on component replacement to the actual catenary OCS in the years immediately prior, temporary staging for the source transition at the substations, then swapping out the circuit breakers to make the actual changeover and dismantling the temp structures for the changeover. Pretty seamless. Everywhere that's gotten constant-tension cat renewal in ex-Pennsy territory already has the OCS components that are compatible with 60 Hz because Amtrak specs that future-proofing detail. So it's mainly working one converter territory at a time starting from Sunnyside converter at the Hell Gate phase break down to wherever the phase break is between Sunnyside and Metuchen converters...refreshing any remaining state-of-repair to-do's with the OCS, returns, and signaling power that haven't been taken care of yet...then doing the staging. Expensive, but not the backbreaker that 25 kV is because the feeders running high atop the poles piping from Safe Harbor don't have to change, and none of the clearances have to change.
I know as you say moving to one voltage is a real bear, but dang, do different standards suck.
Of course I need to toss this out: https://xkcd.com/927/" onclick="window.open(this.href);return false;
After you've gotten everything to D.C. Union changed over to 60 Hz/12.5 kV and put every E-mode vehicle on the East Coast on a diet with slim-down from porky 25 Hz transformer cores to svelte(-er) 60 Hz transformer cores, THEN you can start evaluating 25 kV upgrades. Those are mainly going to be upgrades to the feeders you didn't touch for the frequency change, very expensive upgrades and layout changes to the substations between the former converter sites (Sunnyside, Metuchen, etc.), and upgrades to other sub components at the former converter sites. Because any parts you order for OCS state-of-repair are going to follow Amtrak specs and be future-compatible with 25 kV, you really aren't duplicating efforts breaking the frequency job and the voltage job apart and scheduling them in separate decades lumped in with different state-of-repair jobs. And the weight + cost/maint savings for taking out the automatic voltage taps in the vehicles are far more negligible than getting rid of those 25 Hz transformer behemoths. Which buys you a lot more time to save Connecticut and those painfully short ex-NYNH&H clearances for last. It'll be more manageable to administer such a far-reaching megaproject that way to work the more consequential frequency change first, voltage second.
