I think what he meant was that that the SD9043 and the SD70ACe are effectively the same. This is also not entirely true, but it is a reasonable statement to make. They are both 4300HP V16-710 AC motored 6 axles units with Radial boagies and safety cabs. The 9043s used Siemens electrical gear and are longer and have older style cabs. They also don’t meet Tier 2/3. But in comparison to say and SD40-2 or SD60, they are effectively the same to the power desk.
I disagree. Even if he meant the SD 9043 and SD70ACe are same I find the statement very far fetched.
The SD90MAC (6000 hp) was the designed locomotive, the SD9043 was an makeshift solution using an 710 engine because there was nothing else available.
Don’t forget, the SD70MAC was available since 1993 two years before the SD9043. If you look for a predecessor of the SD70ACe you get to the SD70MAC, I think.
Regards, Volker
Speaking of the UP SD9043MAC’s, I’ve noticed there seems to be several groups of these parked at the Bailey Yard front and center of the camera view. Any idea what UP intends to do with these?
Probably in the process of either reactivation or sale. A bunch have been reactivated lately. I think that as NS has retired their last units for rebuild, the UP is the last railroad operating the model.
The whole series was a bit confusing, with three models-
SD90MAC -the 4300HP convertibles
SD90MAC-H -the subsequent H-engine 6000HP model, none now in use
SD90MAC-H II -improved H-engine model. None in use in North America.
The SD90MAC convertibles have weird electrical systems as a result of the history of their birth, and were not well loved by the shops as a result.
Should be more out there than just on Union Pacific. CEFX bought 40, which should leave them with 30 after the NS acquisition. I imagine most of these are active, although perhaps not necessarily all 30 are still under CEFX ownership.
Appalachian & Ohio has returned their CEFX units, but Indiana Rail Road should still be running a fair number of their CEFX units and I imagine San Luis & Rio Grande still has their two. North Shore Mining also seems to be leasing several. And I imagine many of the others live a nomadic existense as short term lease units that largely go unnoticed by the railfan world, but are generally active.
I wonder when the next step will happen with the CPR fleet. There have been occasional rumors of a NS style rebuilding for them. I believe Hunter Harrison even said once that they were going to undertake such a program to return them to service. Yet they still sit, with no sign of CPR doing anything like trying to sell them, part them out before scrapping the rest, etc.
I imagine they’re not viable for reactivation as-is anymore with the computers probably shot after sitting outside in Winnipeg so long with no care invested into them, but still have potential with a NS style rebuild program.
But even that clock has got to be ticking down pretty quickly after so much time.
SD90MAC in either form is a very different machine to an SD70ACe . To walk around and through you can see some similarities but virtually nothing is the same . I think you can look at a 70ACe as a more refined standardised evolution of the SD90MAC/4300 . By the way this is what EMD call them - SD90MAC/4300 on their Operation Manual .
My take on the 90 is that it was a unique development that originally had to have space for the 20-710 - SD80MAC format . EMD obviously thought the extra heat generated by the 5000 Hp engine needed the larger wider radiator cab , compared to a 70MAC anyway . This was carried over to the 90MAC and in a similar fashion on the 70 ACe . 80s/90s had the larger bulkier traction motors needing larger diameter wheels to keep them off the ground . The HTCRII bogies had a longer wheelbase and wider axle centers too . So unique rad cab/bogies/frame length/ fuel tank made these units different to any previous EMD design .
When the H engine went out the window EMD could revert to a more standardised pattern frame length and bogie wise . You could look at an SD90MAC/4300 as being overbuilt for what it had to do .
Also engine wise I believe the earlier Tier 2 70ACe’s had 4300 gross Hp where the updated Tier 3 version had 4500 . I’m told all 16-710 powered SD90s had the 4300Hp version .
As for the recently upgraded SD90s , as far as I know they chucked the Siemens control gear and inverters and fitted the same Mitsubishi components that the 70ACe’s got standard . I think the 70ACe cab was fitted to meet later crash protection standards , and later cab electronics because they fall in .
You’d think that these would perform much the same as a 70 ACe because they have more in comon with them .
The point is that from the power desk perspective, the SD90s that UP has are the functional equivalent of an SD70ACe. UP doesn’t have 70Macs and in any case, they were all 4000HP. 70ACes can either be 4300HP or 4500HP I believe.
None of UP’s have been upgraded. They are still all Siemens gear. the NS units are being converted to SD70AU which means swapping the AC system and replacing the cab. I think the computers get updated too.
Also, all the SD9043s got reactivated. Roseville had a bunch come in as well. Power crunch.
Also, NorthWest, to the best of my knowledge, none of those terms are official. EMD called them all SD90MAC.
H-Mac was a fan term.
EMDs Operators Manuals , for Phase 2 versions , say .
Electromotive - SD90MAC/4300
October 1998
Pn O00352EP
Or
Electro - Motive
SD90MAC Locomotive
(6000 HP - Phase 2)
November 1999
Pn O0036EP .
The specs I have for the SD70AH show a mass of 430,000 pounds or approximately 195 metric tonnes .
SD90MAC/4300 isn’t a Phase 2. There were SD90MAC/4300s that were phase one, they look mostly (but not completely) like an SD80MAC. There are SD90MAC Ph1 6000HP. which have the angled roof profile over the prime mover, but look the same as the SD90MAC/4300 in most other respects And there are the SD90MAC-Ph2 which were also 6000HP, but have the cabs that look more like the SD70ACe cab. I believe the Ph2 also only have the 2 larger radiator fans as seen in the ACe. There was never a phase 2 unit with a 710 in it.
That must be correct , the 90MAC/4300 manual shows diagrams of units with the earlier cab and 3 rad fans . It mentions the engine as a 710 G3C-ES .
The 90MAC Phase 2 manual shows the later cab and two rad fans .
It adds one word:Adhesion. Diesel Electric loco’s are entirely dependent upon the concept of adhesion or the ability of a smooth steel wheel to maintain traction against a smooth steel rail in all conditions. Since the friction point of a round wheel against a flat surface is less than the size of a dime, the more weight you can put on that one point times 8 or 12 wheels determines the amount of tonnage you can pull without losing that adhesion in the form of traction… The cost of concrete or metal plates is a small number compared to the cost of a locomotive. The less of those you can use to pull he same freight, two instead of three for instance, saves the fuel cost and depreciation of one whole unit from point A to point B. Those avoidance costs go right to the bottom line.
How many units per coal train?
Almost certainly 3 (for the lengths given): two in front and one DPU at the rear. Node can be heard moving accordingly. NS (ex-Southern) runs considerably longer coal-gon and hopper consists with the same arrangement; when they are heavier (loaded), you’ll see symmetrical 2-unit power at either end.
Normal power in each instance was two units.
As most AC locomotives may have some form of traction control when the computer is to limit the current to the traction motors as part of the way to also gain adhesion nozzles are aimed at the wheels when sand is sprayed at the wheels to gain traction.
Incorrect, EMD used concrete weights in BL2’s, GP7’s and GP9’s to name a few.
NS and CSX have different power philosophies. Through my CSX employment career CSX did not utilize DPU’s. System standard for coal trains has been two units ever since the Dash-8’s came on the property in the very late 1980’s. With the number of cars per train increasing as improved locomotive technology permitted.