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Trains News Wire FLASH: Amtrak resumes limited service south of Baltimore
No. The old PRR catenary is essentially trolley wire that is not under tension and basically just “hangs” above the tracks. The “new” wires between New Haven and Boston are constant tension.
Can the existing wire be converted to “constant tension” or must everything existing be taken out and new “stuff” be installed?
Is this “constant-tension” wire?
The overhead on the Pennsy lines can expand and sag on hot days or shrink and pull apart on cold days because it is essentially one long wire. Newer overhead is made of short lengths that are anchored at one end and have a counterweight at the other end to keep the wire stretched when it expands.
Diesels to the rescue
as no one here seems to work for Amtrak ,and I have 36 yrs of service and it happpened in my section of control,. the problem was not the wire. the cause is still under investigation.
the main problem is that dispite all 3 tracks having wire damage, transportation cannot think out of the box to move trains. the ODENTON MW base is a half mile north of where the damage was. if they had let the ET catcar out instead of 1 diesel to try to move dead trains, they could have had 2 tracks back for electric operation by 1230pm with temorary repairs.
as it was they didn’t get 1 until 300pm, 2 track after 5 and 3 track until after 7pm. the trains that were stuck still had overhead power north of Grove interlocking. the 3 trains stuck at Grovecould have been coupled together, pans dropped , an thenm have the diesel tow all 3 trains south of Bowie Md where they could have raised their pans and been on their way to Wash DC. As it was, the lineman had to work “OLD SCHOOL” off 40 ft ladders and skateing the poles to make intial start of repairs.
the continued inability of our transportation managers to make a decision with out being critized by people who do not have any experience moving/running trains and who are not at the site of the problem is sad. when I came on in 1977, the Old Time bosses would have never let this kind of thing happen.
but between the “college boys” and the bean counters worried about the monies being spent instead of the passengers needs
are sorely ignored.
As for the wire contruction. constant tension is expensive to build. and while it works on the Boston end with just 2 wires,
they are not sure how it will work with just 2 wires with the amount of trains and the current draw at 11kv on the old PRR system. plus if the wire breaks on contant tension, the wire runback damage and stress is greater then the PRR 3wire standard when damage. and for as for infomation , the main damage was to 2 steady spans that hold the wire in al
Actually, while the catenary is manually adjusted seasonally by means of turnbuckles, like with “constant tension” the wire is segmented at one mile lengths for the simple reason that it that constant length is impossible to maintain. Furthermore, the PRR Catenary is Three Phase AC, with the phases rotated at each one-mile segment, so it should have been simple to replace the wire of the one segment that was affected over each track at Bowie. It shouldn’t have taken a full day to finish the job.