SD70 - MagnumMacKivler/RLCPT2 GitHub Wiki
An Illinois Central locomotive sits in fresh paint. Photo credit Illinois-Central.Net
The SD70 was EMD's entrance into the 1990s with the now-faithful 710G3 engine. With a new transition from the SD60, SD60M, and SD60I, Electro-Motive now offered most optional features (like extended range dynamic brakes) as standard; the major change, however, came in the High Traction Control-Radial (HTC-R) truck, experimented with a lone SD60 engine and the experimental SD60MAC, was now standard issue on the SD70 series.
Three demonstrator SD70Ms, 7000-7002, show off their power on a loaded coal train (with a research passenger car behind it) in May of 1993 in Manchester, Georgia. Photo credit Casey Thomason
With new federal law requirements, all locomotives were mandated to have the wide cab that was only optionally offered by Electro-Motive. (Most railroads purchased the wide cab around this time anyways for crew comfort and for better visibility.) This new law led to the SD70M and AC-relative locomotive SD70MAC. Like the SD60I, railroads also requested an isolated cab version of this locomotive, and thus the SD70I was created. Canadian National railroad was the sole purchaser of the SD70I locomotive
A Canadian National SD70I sits with a coal train in Chicago, Illnois, pictured in fresh paint in January of 1996. Photo credit Eric Larson
Later SD70M locomotives featured a more angular cab that was used on the SD70ACe along with flared radiators (much like the SD45.
A late production Union Pacific SD70M sits 11 months after it was built relatively clean in a Kansas City, Kansas yard. Notice the flared radiators and newly design cab. Union Pacific was a major purchaser of the SD70M locomotive type. Photo credit Warren Calloway
Total production of the original DC SD70 series from 1992 to 2005 came out to 122 SD70s (standard cab), 1609 SD70Ms, and 26 SD70Is.
PT-Specific Information
| General Info | - |
|---|---|
| Prime Mover | EMD 16-710G3B |
| Horsepower | 4000 |
| Truck Type | EMD HTC-R |
| Axles | 6 |
| Traction Motors | 6 |
| Minimum Weight | 388,000 lbs ⚠ |
| Maximum Weight | 400,000 lbs ⚠ |
| Model Base Speed | 74 MPH |
| Top Speed | 74, 80, 86, and 92 MPH |
| Electrical System | - |
|---|---|
| Generator Max Current | 9900 Amps |
| Max Traction Motor (TM) Current | 1650 Amps |
| Max Continuous TM Current | 1230 Amps |
| Traction Motor Type | DC |
| Factor of Adhesion | 35% |
| Transition Mode | Automatic, no Selector |
| Transition Groups | 1 |
| Transition Shunts | 1 |
| Generator Transition | Yes |
| Traction Control | ETC |
| Dynamic Braking (DB) Mode (if used) | Electrical Blowers |
| DB Max Current | 1000 Amps |
| DB Max Continuous Current | 945 Amps |
| Blended Braking | No |
| Miscellaneous | - |
|---|---|
| Head-End Power (HEP) | No |
| HEP Power Consumption | N/A |
| HEP Standby/Run Mode | N/A |
| Load Ramp Speed | 2 Amps/Tick |
| TM Overload Protection | No |
| Starter Mode | Manual Primer, Manual Start (2) |
| Air Brake Schedule | 26-L |
| Compressor CFM | 254 (Gardner Denver WBO @ 900RPM) |
| Main Reservoir Volume | 35 Cubic Feet |
Notes
⚠: Not Verified or Educated Guess
(2): Later units were produced with fully automatic starters.