The rebuild program features a complete electrical upgrade, replacing the existing Siemens electrical equipment, including the inverters, with Mitsubishi electronics. The existing cab is replaced with a new isolated SD70ACe cab along with a number of other smaller changes to the locomotive during rebuild.
The changes bring the locomotive up to essentially the same mechanical specification as EMDs SD70ACes. The first two SD70ACUs released from Altoona were NS Nos. 7248 and 7283 in January. Both units were sent to Progress Rail’s Muncie, Ind., plant for testing. A third unit, No. 7319, emerged from the Altoona paint shop this week.
To accelerate the program, Norfolk Southern will have EMD rebuild a number of SD90MACs concurrent with the ongoing program at Altoona. The first four, NS Nos. 7262, 7267, 7280, and 7295 have already been shipped to Progress Rail’s Muncie plant to begin the rebuild program there.
ANDREW WINEGAR from IOWA: Same with the UP (Ex Santa Fe) SD75's that NS purchased a couple years ago. More 4,300HP locos at a fraction of cost of an SD9043.
They look good! I hope they are successful.
The Melco inverter system (IGBT) as applied to the 70ACes' is a very robust system-with a smaller parts count than the older Siemens GTO-based equipment. By way of example, each Siemens inverter (of which there are two) required its' own dedicated Siemens computer, in addition to the EMD EM2000 (locomotive control computer). By copmparison, each Melco inverter is controlled by a card within the EM2000.
I've seen a few of these units in their "as is" condition in Crewe Yard. The transformation is amazing. I'll bet it must be fun working at Altoona.
I'm curious about the change from Siemens to Mitsubishi electrical equipment. In my 30 years experience with (stationary) industrial electronics, I have found Siemens equipment to be expensive but reliable, and Mitsubishi prone to failure and parts and service almost impossible to obtain. Hopefully their locomotive equipment is different.
Thanks Andrew. I was wondering if they had the 265 engine and yes it seems Altoona just keeps doing great work
"Ingenuity"…oh, sorry–that used to be CP's slogan.
I have to wonder if Hunter might give Jim a few of the extra SD9043s from his railroad–break-up gift, you know…"no hard feelings".
I had to do some research as to which prime mover these had. It turns out NS bought 100 stored SD9043MACs, meaning they had the 710 engine, not the unreliable 265H. Which means NS didn't have to repower them or make them Tier-4 compliant, as their powertrain remains unchanged. It's very smart of NS to do these rebuilds- they get a near-new locomotive with modern electronics at a fraction of the cost of a new one.