• U23C

  • Discussion of General Electric locomotive technology. Current official information can be found here: www.getransportation.com.
Discussion of General Electric locomotive technology. Current official information can be found here: www.getransportation.com.

Moderators: AMTK84, MEC407

  by TerryC
What is the horsepower rating for Conrail's U23Cs? Conrail Cyclopedia gives the rating as 2,200, but I thought it was 2,250; the same as the U23B. What was it like to watch them and/or ride them?
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  by Allen Hazen
I think there may be a bit more loss in the transmission with a CC unit than with a BB, so it may be that a dynamometer car test would show a U23C as a bit less powerful than a U23B with the same engine, but I doubt the difference would be as great as 50 hp. (My recollection of the 1984 Dash-8 prototypes is that the B32-8 was quoted as having about 10hp more power tan the C32-8, but that's a hazy memory of figures I wouldn't be too confident of anyway.)
George Elwood's "Fallen Flags" railphoto site has a number of Conrail locomotive documents (go to Conrail in the site index, then click on "Locomotives"). I looked at one, from 1980. It doesn't quote power for the different models, but does give tractive effort and minimum continuous speed-- assuming the tractive effort figure is for t.e. AT the minimum continuous speed, this would allow calculation of the drawbar horsepower (typically, for locomotives of that era, about 82% of the nominal engine rating) AT THAT SPEED. Eyeballing (I didn't do the arithmetic CAREFULLY or with a calculator), it looks as if Conrail may have thought the U23C was about 25hp less powerful than the U23B-- but that might just be a rounding-off error (minimum continuous speed is given to the nearest tenth of a mph, and tractive effort to the nearest thousand pounds: so rounding-off errors could easily be more than 25hp).
My guess is that PC/CR's U23C were officially 2250 hp (the conventional locomotive rating is engine power input to the main generator, and so does not take transmission losses into account!) and that the 2200 you found in the Conrail Cyclopedia is either a typo or someone's decision to round everything downward. But that's a GUESS.

  by TerryC
Thank you so much Allen Hazen. Where is this section of Conrail documents in the Fallen Flags website? That was not quite clear. Thank you again.

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  by LCJ
TerryC wrote:What was it like to watch them and/or ride them?
I remember clearly when these units arrived on the property. They were my first experience with new locomotives (whoopie!). They were much nicer to work with than what they replaced (a mixed bag of RSD12s mu'd w/ GP9Bs, RS32s, GP20s, etc.). Selkirk received units 6710 through 6718 (later renumbered 6910 to 6918).

6714 and 6716 were equipped with hump cab signals with three positions -- green for shoving toward the hump, yellow for humping, and red for stop. Signals were controlled by the conductor on the panel up in the hump building.

We used single U23Cs as pullers on the East End of Selkirk to pull cars out of the class yard to make up trains in the departure yards. A double unit set was used on the hump (with pilots trimmed to clear the retarders). Two U23Cs would handle any train the humpers had to shove or pull back. They were used for this purpose until the SD38/MT-6 combos replaced them in the early '80s.

The cabs were very warm in winter, with a heater blower that made very little noise -- a definite improvement over the stuff they replaced. Some ground folks complained they were too warm for times when the brakemen were suited up for the terrible Selkirk blowing cold. We'd just say, "Well -- go back out there, then."

Cabs were painted dark green -- typical for PC units -- changed to light grey in the CR period.
Last edited by LCJ on Sat Jun 25, 2005 12:59 pm, edited 1 time in total.

  by MEC407
Thanks Allen for the technical info, and thanks LCJ for sharing your memories!

  by Typewriters
Both U23B and U23C were given ratings of 2250 HP. This rating, as for the majority of diesel-electric locomotives, is "horsepower for traction." This means that the diesel engine delivers 2250 HP to the generator; there is no distinction between U23B and U23C, or, for that matter, either type with either straight DC or AC/DC transmission.

Naturally, characteristics at the drawbar would differ between the four and six axle variants, but that does not affect the advertised horsepower rating.

-Will Davis

  by TerryC
THANK YOU ALL FOR YOUR EXPERIENCES, INPUT, MEMORIES, AND YOUR POLITENESS. It is too bad that none of these locomotives were saved.

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