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Re: Trolley Poles and Pantographs
Author: Dr Zarkoff
Date: 10-18-2015 - 19:39
>If you will look at the SN employee time table from Rio Vista Junction to Riverview you will find that the passenger trains had to go 52.34 mph average to stay on time. This average speed included station stops.
OK, I did, and it says: Rio Vista Jct mp 57.78, Riverview mp 86.95. Subtracting the two figures results in 29.17 miles. Time of EB Meteor at RVJ: 7:01 AM; time at Riverview 7:35 AM, no intermediate stops. Assuming a perfect run, this is 34 minutes to go 29 miles, which comes to 1:06 per mile (one minute, six seconds per mile). 1:07/mile is 55 mph. The Comet, and all other trains which had about 8 flag stops in between these two locations, had running times 6" longer to allow for the stops, giving a total of 40", or 1:12/mile, which is essentially 50 mph.
>Westinghouse 322-E motors with 36 inch wheel trucks show a top speed of 77.3 mph with 1500 volt trolley voltage and 50 amp current per motor with this gear ratio.
After consulting the characteristic curves in Richey's and adjusting for gear ratio, I get 67 mph @ 50 amps.
Don't forget that the motors cars are also usually towing two trailers in addition to propelling themselves. Additional loads tend to reduce total speed (also consult your stops/mile and speed to horsepower per ton tables).
Yes the SN's South End cars were fast by typical interurban standards, just not to the tune of more than the low to mid 60 mph zone.
OK, I did, and it says: Rio Vista Jct mp 57.78, Riverview mp 86.95. Subtracting the two figures results in 29.17 miles. Time of EB Meteor at RVJ: 7:01 AM; time at Riverview 7:35 AM, no intermediate stops. Assuming a perfect run, this is 34 minutes to go 29 miles, which comes to 1:06 per mile (one minute, six seconds per mile). 1:07/mile is 55 mph. The Comet, and all other trains which had about 8 flag stops in between these two locations, had running times 6" longer to allow for the stops, giving a total of 40", or 1:12/mile, which is essentially 50 mph.
>Westinghouse 322-E motors with 36 inch wheel trucks show a top speed of 77.3 mph with 1500 volt trolley voltage and 50 amp current per motor with this gear ratio.
After consulting the characteristic curves in Richey's and adjusting for gear ratio, I get 67 mph @ 50 amps.
Don't forget that the motors cars are also usually towing two trailers in addition to propelling themselves. Additional loads tend to reduce total speed (also consult your stops/mile and speed to horsepower per ton tables).
Yes the SN's South End cars were fast by typical interurban standards, just not to the tune of more than the low to mid 60 mph zone.
