RSD-4 and RSD-5, 1600 HP for traction; RSD-12, 1800 HP; RSD-7, first version (DL-600) 2250 HP; RSD-7 (second, or DL-600A) 2400 HP; RSD-15, 2400 HP. (The single MLW RSD-17 was as the RSD-15.) RSD-15 also known as DL-600B.
The RSD-4 contained the same GT-581 generator employed in the RS-3 and FA-2/FB-2, while the RSD-5 employed the GT-566 normally found in 2000 HP and 2250 HP passenger locomotives. The RSD-12 changed yet again, to the GT-586, used thereafter.