[PRCo] Re: PCC__Speeds

[boris6 at volny.cz]

When you look at 1700s Westinghouse schematic diagram, will see
that these are suitable for change from 50% to 67% field
shunting, so they were possibly capable of faster acceleration
after the accelerator resistance was short-circuited by M2
contactor. Of course, the "overspeed relay" (this term is used in
diagram) somes into play when car speed reaches the adjusted
value of that relay. But don't know, if that 67% shunting was
used.

Boris

----- PŮVODNÍ ZPRÁVA -----
Od: "Jim Holland" <PghPCC at pacbell.net>
Komu: pittsburgh-railways at dementia.org
Předmět: [PRCo] Re: PCC__Speeds
Datum: 6.10.2003 - 9:01:11

> Good Morning!
> 
> 
> > rogertrolley.1 at juno.com wrote:
> 
> > Jim Holland Commenting about 42 mph top speed for the
> > PCC's brings up the speed subject again.    I belive
> > most
> > PCC's were quite capable of reaching speeds in excess
> > of 42mph.
> 
> 
> The story I told related to this speed limitation
> stated Just
> That  --  we  WERE  doing more than 42-mph!    Outbound
> with a
> 1700-series Interurban on Library, PM rush, full load,
> heading
> south from Hillcrest thru Lindermere the Limit-Relay
> caused the
> power to cut which means we reached 42-mph.    We then
> rolled
> downhill and physics tells us we gain momentum at such
> times.   
> It wasn't until the car  *slowed*  to 42-mph rolling
> uphill
> toward Brightwood that we got our power back.
> 
> How fast were we actually going    ---- DoNut Know!
> 
> *Possibly*  as fast as 50-mph or somewhat close to it.
> 
> And I believe that a study of physics would indicate
> that the
> motors would self-destruct at much over 50-mph.    I am
> hard
> pressed to believe that without some actual 
> *controlled* 
> experiments.    Fred has already stated this.
> 
> One former SF-Muni operator claimed that a policeman
> clocked him
> at over 55-mph on the N-Judah.    Anyone familiar with
> SF knows
> that this line runs along the short ends of the blocks
> along
> Judah so that there is an intersection about every
> 300-feet!   
> Fifty-Five--mph on city streets  --  absolutely  NO 
> way.
> 
> And remember that someone claimed that one PRCo PCC was
> doing
> 90-mph  UPGRADE  on the prw on 87-Ardmore!
> 
> 
> <><><><><><><><><><><><><><><><><><><><>
> 
> James B. Holland
> 
> _ Holland  Electric  Railway  Operation....... 
> "O"--Scale St.-Petersburg Trams Company (SPTC)
> Trolleycars and "O"--Scale  Parts
> including Q-Car
> mailto:pghpcc at pacbell.net
> 
> _ Pennsylvania Trolley Museum
> http://www.pa-trolley.org/
> _ Pittsburgh  Railways  Company  (PRCo),
> 1930  --  1950
> _ N.M.R.A.  Life member #2190;
> http://www.nmra.org
> 
> <><><><><><><><><><><><><><><><><><><><>
> 
> 

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