• General Electric U-Series Manufacturer Data

  • 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 Allen Hazen
About a dozen posts up, the question of when CHEC ("Constant Horsepower Excitation Control") was introduced came up.
Data point.
I have the 1974 edition of the (Simmons-Boardman Publishing, published for or in collaboration with the AAR Mechanical division) "Car and Locomotive Cyclopedia," published (according to date on title page) in … 1974. This isn't quite a General Electric document, but… Chapters aren't signed, so it isn't clear who actually wrote various parts: Simmons-Boardman employees, AAR committee members, or manufacturer staff are all in principle possible. However, it LOOKS to me as if the information in the technical chapters was PROBABLY provided by the manufacturers: the descriptions of GE, EMD and MLW engines and control systems differ enough in format and organization that I think the final writer must have been essentially cutting and pasting material provided by the three manufactures. SO: for the moment I am tempted to think the Cyc should be accorded "almost official" status.

Punch line. The half-page description of CHEC (page S17-2, near the beginning of the section on GE control systems) says that General Electric locomotives with AC transmissions have CHEC. No suggestion that it is an option, or that it is something that is about to be introduced, just a blanket statement. So I think a cautious, minimum, guess is that any U-series GE unit with AC/DC transmission built in 1975 or later had a CHEC engine, and that it is likely that CHEC became standard a bit earlier: 1974 maybe.

What units would this cover? (Many late U23B had AC transmission, but for the moment I'll limit myself to models with 16 cylinder engines.) The last U33C (for Southern Pacific) and U36B (the units ordered by Auto Train and a few years later delivered to Conrail) were built in 1974: so, maybe-maybe-not. Units built in or after 1975 include (i) Amtrak's P30CH, (ii) the last five U30B (for SLSF), (iii) a few late U30C for BN, (iv) a large number of U30C (two orders, one in 1975 and one in 1976) for UP, and (v) some U36C for ATSF and NdeM (both railroads had sizeable orders built partly in 1974 and partly in 1975). (Tally from roster at the mack of Greg McDonnell's "The U-Boats.")

(Pretty puny piece of information compared to Will's posts, but the best I could do!)
  by Typewriters
Good stuff, Allen.

I think it's likely that the reason I cannot find a specific mention of CHEC in official materials is that the CHEC excitation is included as part of the engine monitoring system introduced as a part of the "1975 improvements" that were phased in over the two years prior to the introduction of the "New Series" or Dash 7 line. If that is indeed the case, and it appears to be from the manufacturer information I can piece together here, then your assumption is right on target about the date of introduction.

-Will Davis
  by Allen Hazen
…Though CHEC is not one of the 58 improvements listed as part of the pre-(New Line) design changes in your blog post (*) on the New Line. My own guess is that CHEC would have been just bait earlier, though the description in the 1974 "Car and Locomotive Cyclopedia" is at best weak evidence for this. Still, it couldn't have been much earlier, since it apparently wasn't used on the U34CH of 1973.
  by Allen Hazen
Sorry about that. Since GE had devoted a paragraph to CHEC, under that name, in the material it (I assume) provided for the 1974 Cyclopedia, I was naively looking for it as a named item on your list!
(B.t.w. -- in case other people are wondering what list we are talking about, see the "Railroad Locomotives" blog post on GE's 1977 line of locomotives at
http://railroadlocomotives.blogspot.ca/ ... chive.html" onclick="window.open(this.href);return false; .)
  by obsessed railfan
Pneudyne wrote:These had KC92H (right-hand drive) or KC92J (left-hand drive) control stands. Although some later exports were fitted with newer controller types, the KC92 seems to have been used through the 1970s at least.
I often wonder if the early domestic Universals would have been more popular with crews if GE had installed KC92 export controllers once they discovered their domestic controllers were not well liked. A simple, easy to use controller with selector, 8 notch throttle, and reverser. It also had years of proven service, being the standard export controller since the Universal line debuted in 1956. I am not sure if it was used in any pre Universal locomotives. The KC92 also looks good, compared to the domestic monstrosities.

It seems the AAR control stand first appeared on export Universal roadswitchers around the same time as domestic Universals. But the KC92 seems to have been very well liked since it could be ordered as an optional controller through at least the mid 1970s as previously mentioned. I have seen a U15C cab photo with an AAR control stand, but conversely I have also seen a late U20C cab photo with the KC92.

Once again, it seems to be another classic example of the "two sides of GE", with the export Universals being extremely popular, but an entirely different story with domestic Universals.
  by obsessed railfan
Typewriters wrote:The A variant of the manual is unknown, but the GEJ-3856B variant published beginning in 1972 is quite common.
The A variant from 1969 was edited to include the U36 model. Additionally, the 1973 C variant was edited to include the U18B.