Can someone tell me the difference between a SD-70ACe and a SD-70M-2? They look the same if I am correct. Just want to know the differences that is all.
Thanks.
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Originally Posted by Tim Lewis:
Can someone tell me the difference between a SD-70ACe and a SD-70M-2? They look the same if I am correct. Just want to know the differences that is all.
Thanks.
First, there are no "-" in the EMD model designations, thus you are inquiring about SD70ACe vs. SD70M-2.
Second, the SD70ACe is an AC traction unit with various cooling air intakes for the traction inverters in the long hood. The SD70M-2 models are DC traction, and thus have no traction inverters.
Tim,
I read online that Norfolk Southern used to order SD70M-2 with DC traction motors while most of the other Class 1 Railroads (except Canadian National) started buying SD70ACe with AC traction motors. Similar to how they kept ordering locomotives with standard Spartan cabs while all other Class 1 railroads ordered the wide-cab locomotives until they had to change, it seemed like Norfolk Southern kept ordering locomotives with DC-traction locomotives. Only in the last few years did they start ordering locomotives with AC traction motors. So the initial orders from EMD from the mid-2000s were SD70M-2. The recent orders, including the Heritage locomotives were all SD70ACe. The SD70M-2 had the standard wide cab while the newer SD70ACe have the isolated cab. The antenna housing on the roof of the operator cab is different. The panels behind the operator’s cab on the conductor’s side are also different, maybe due to the differences Hot Water mentioned earlier in this post. Enough with the words – Here are pictures of both taken from a similar angle.
These are just my opinion,
Thanks,
Naveen Rajan
The antenna differences are for PTC. 1018 is equipped for it, 2754 is not (at least at that moment in time). As HW pointed out, look behind the cab to tell the only "noticeable" differences between the two models.
On on a side note, despite being late to the "AC" traction game, NS has become a fan. They're currently retrofitting the "spartan cab" D9-40Cs (also known as Top Hats) to AC traction and conventional GE Safety Cabs.
Originally Posted by Southern6482:
The antenna differences are for PTC. 1018 is equipped for it, 2754 is not (at least at that moment in time). As HW pointed out, look behind the cab to tell the only "noticeable" differences between the two models.
On on a side note, despite being late to the "AC" traction game, NS has become a fan. They're currently retrofitting the "spartan cab" D9-40Cs (also known as Top Hats) to AC traction and conventional GE Safety Cabs.
If I'm not mistaken, and I'll ask my best friend's father who is the head manager in the locomotive shop for NS in Cincinnati tomorrow. I want to say that NS has only converted two D9-40C's into AC, and I think they are getting Cresent Cabs as well.
Railfan9, those are the D8-40Cs getting the Crescent Cabs - they're going to stay DC traction. That work is being done at Roanoke. The D9-40Cs are being converted to AC with GE cabs. Eventually, the D-44CWs are to be converted to AC too.
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Originally Posted by Southern6482:
Railfan9, those are the D8-40Cs getting the Crescent Cabs - they're going to stay DC traction. That work is being done at Roanoke. The D9-40Cs are being converted to AC with GE cabs. Eventually, the D-44CWs are to be converted to AC too.
Thanks. I completely got my locomotives mixed up lol.
I had believed that cool air intakes on the rear lower side of the long hood were open grids on the ACe and horizontal slats that closed on the M-2s when they first came out. Maybe they were modified models for cold air climate RR's?
I don't believe that can be used anymore? I think they're all open grids now?
ace:
M-2
Originally Posted by Engineer-Joe:
I had believed that cool air intakes on the rear lower side of the long hood were open grids on the ACe and horizontal slats that closed on the M-2s when they first came out. Maybe they were modified models for cold air climate RR's?
I don't believe that can be used anymore? I think they're all open grids now?
ace:
M-2
If I'm not mistaken those portions of the long hood are the dynamic brake radial grids with a 54" diameter cooling fan, and the cooling air intakes are down low.
Originally Posted by Railfan9:
Originally Posted by Southern6482:
The antenna differences are for PTC. 1018 is equipped for it, 2754 is not (at least at that moment in time). As HW pointed out, look behind the cab to tell the only "noticeable" differences between the two models.
On on a side note, despite being late to the "AC" traction game, NS has become a fan. They're currently retrofitting the "spartan cab" D9-40Cs (also known as Top Hats) to AC traction and conventional GE Safety Cabs.
If I'm not mistaken, and I'll ask my best friend's father who is the head manager in the locomotive shop for NS in Cincinnati tomorrow. I want to say that NS has only converted two D9-40C's into AC, and I think they are getting Cresent Cabs as well.
More crescent cabs? Ugh.
Originally Posted by naveenrajan:
Thanks for those pictures Naveen I love NS engines.
Norfolk Southern must not have converted all their standard cab Dash-9s to wide-cabs yet, as I just saw 8787 (with standard cab) outside my workplace this morning on the Iowa Interstate Railroad line, leading a train of ethanol tank cars & grain hoppers from the ADM plant in town.
These are just my opinion,
Thanks,
Naveen Rajan
Originally Posted by Southern6482:
Railfan9, those are the D8-40Cs getting the Crescent Cabs - they're going to stay DC traction. That work is being done at Roanoke. The D9-40Cs are being converted to AC with GE cabs. Eventually, the D-44CWs are to be converted to AC too.
NS has only converted two D940-Cs thus far to widecabs and I believe D840-Cs. So yes, the vast majority are still top hats (for now).
