Western Railroad Discussion > What locos have DPU

What types of modern wide nose engines have DPU capabilities?
The only 2 I can think of are SD70MAC and AC4400. Have the railroads every put a DPU dome on a Dash-9 or SD70m?
Steven

The new ES44's have DP capability, SD90MAC's, AC6000's, SD70ACe's. I don't know of any SD70M's or Dash 9's, but UP equipped the 9300 series C40-8's with DP capability. I saw only one in DP service ever.

Huh? I do believe that BNSF has several Dash 9's with DPU capabilities.

UP:
SD9043MAC
SD70ACe
AC6000CW
C60/44AC's
AC4400CW (including ex SP)
C40-8 (some of the 9300 series)
ES44AC
Im surprised that the SD70M's didnt come equipped with DPU software

BNSF:
SD70MAC
SD70ACe
ES44AC
ES44DC
C44-9W (Not sure about the ex ATSF)
AC4400CW

DPU (what was commonly called "Locotrol" up until the mid-'90s) is most easily installed on locomotives which have electronic air brake, not "conventional" locomotive air brakes. That's because the electronic air brake package is easier to "connect" electronically-and-pneumatically to the DPU electronics, and also eliminates a ton of pneumatic hardware. Older locomotives with "Locotrol" with conventional air brakes had to have a large air tank/valve device installed to serve as the interface between the Locotrol electronics and the locomotive brake pipe. I recall many of those devices were from a company called Davis & Metcalf in the UK.

The big batch of SD70Ms, the 1400+ built for UP in 2000-2004, were all designed for and built with conventional air brakes so including DPU with the as-built conventional air brakes would have entailed a lot of extra air piping and equipment, and building with electronic air brakes would have entailed re-engineering the entire air brake system.

The primary functional difference, by the way, between "DPU" (distributed power unit) and the old "Locotrol" is that DPU typically allows up-to-2 remote consists in the train, whereas "Locotrol" could only control 1 remote consist in the train. Equipment-wise, "Locotrol" itself was quite bulky. Locotrol installations in the 1980s required several electronics boxes the size of several large suitcases (remember the SP 8300 and 8350 series of SD40T-2s with the extra-long "snoot" noses?). Earlier versions of Locotrol were often installed in dedicated remote-control cars to which regular locomotives would be coupled and MU'd, for mid-train power. The BN, C&NW, CP, Southern and SP all had "radio cars" for that purpose back in the 1970s-80s. The first Locotrol operator that did not have "radio cars" for the remote consist was, I believe, Detroit Edison, which had a fleet of about 26 SD40s and U30Cs built around 1969-1971, some as Locotrol leaders, some as Locotrol remotes, the remainder as non-Locotrol units. The DEEX units were used to power Detroit Edison unit coal trains from mines around Washington, Pennsylvania to Monroe, Michigan over Penn Central (later Conrail).

What was inside those "radio cars"? The Locotrol electronics and air equipment was probably about the size of two or three refrigerators. The rest was concrete for ballast.

Mad_dog quoted: "AC4400CW (including ex SP)"


Whoa!!!!! Only the former SP 100-199 were sans DP capability, and some of them may have since been retrofitted as they became UP units. SP 200-389 all had DP capability, although I can't recall for sure, it was either the 200-203 or the 300-303 that came without it but were immeadiately retrofitted.

And "BNSF:
SD70MAC"

The former BN 9400-9712 were delivered without DP capability. The 9712 has been retrofitted along with some 9500, 9600, and low 9700s. 9713 and up all came with DP.

Double K

With Locotrol III (Harris Box) like found on BNSF 960 class dash-9's, up to 4 remote consist (not including the lead consist) can be in a train.

With IDP, (all other Dash-9's(excluding 600 class), AC4400CW's, ES44DC/AC, some but not all SD70MAC's as noted above, SD70ACe) up to 5 remote consist can be in a train.

Just some useless DP info.

Now do BNSF SD75M's have IDP??? It would have to be the higher numbers (8251+++ ???) as they have ICE screens. Haven't been around many of these units, as they are stuck somewhere else on the system.

Yes BNSF SD75's 8251-8275 have DP. They have been in DP service, being added to and removed from the head end as DP leaders and the rear end of trains as DPUs at Sheridan, WY for the last year or so. (Some SD75s have been stripped of their DP radios and other equipment though so we can't use just any of them).

If anyone has a complete list of BNSF SD70MAC DP units I'd like to have a copy. The hostlers have to continually check on the computer each individual unit coming towards town to see if it is DP equipped to figure out which can be used for a leader or rear end DPU. It'd be nice to have an actual list of DP MACs.

keep in mind that not all UP ACe units have DPU capability. 1996 is one that pops in to my mind.

YM

And to add to the list, the SP GP40X's had an early version of the Harris System and as I remember
were capable of two remote sets. I also seem to remember some talk that the last 100 or so UP SD70M's
were to be DPU equipped, don't know if that ever happened.

NS C40-9W 9212 - 9226 and Various 7500-7600 series ES40DC are equipped with IDP.
NS 7200-7216 / CSX 4590-4612 (Former CR SD80MAC) also have IDP but neither road uses it.

Some of the earliest CR C40-8W have Locotrol III, just like with the SD80 neither CSX or NS have used the system and it has fallen into a state of disrepair with many units missing parts.

A earlier post made mention how normal airbrake equipped units are rare, the C40-8W's are one such example of Locotrol III equipped units with 30CDW brake. These and some of the retro-fitted CN C44-9W's are some of the only units I can think of with this configuration.