In 1968 Germany computerized their locomotive numbers, they were the first in Europe to do so. A three part numeric numbering system replaced the former system that included a letter to denote the traction type. Current German locomotive numbering follows a three part system:  1. traction type/class type 2. three digit running number 3. computer check digit. Thus for one loco with number 151 036-1 its number translates to 1 (electric traction) 51 (class) 036 (running number) and 1 (computer check digit). Before 1968 this loco would be numbered E51 036 if it existed then.

Traction types are numbered 0-9: 0- Steam loco 1- Electric loco 2- Diesel loco 3- Shunting loco 4- Electric railcar 5- Battery Electric railcar 6- Diesel railcar 7- Diesel railbus 8- Electric railcar trailer 9- Diesel railcar/railbus trailer.

The last digit in the German loco numeric system is the computer check digit, it serves to double check that the other digits can be verified correctly. Thus a rather complicated computation follows: multiply class and running number digits alternately by 1 and 2, resulting digits are added together and their sum deducted from the next whole number.  For loco 151 036: 1×1=1, 5×2=1+0, 1×1=1, 0x2=0, 3×1=3, and 6×2=1+2 / 1+1+0+1+0+3+1+2=9 / 10-9=1 thus the 151 036 is identified as an electric loco, and its complete number is 151 036-1.

The German locomotive number is identified on the end of each locomotive and in most cases both ends, and a second identifying number is located on the sides of each loco called the European Vehicle Number (EVN).

Reference material: German Railways – Part 1: Locomotives & Multiple Units of Deutsche Bahn, published by Platform 5, written by Brian Garvin.