-The maximum number of characters in a cable number is 15.
-You may use any characters except quotes ('), double quotes (“), backslashes (\), blank spaces ( ) or decimal points (.).
-Each signal type uses its own cable number template.
-The length of a cable number depends on the number of variables and constants in the cable number template. The two variables are numbers (#) and constant alphabetic characters (?).
-The number of characters in a cable number is based on the number of variables and constants (“#” and “?”) in the cable number template that you use for a given signal type. For example, you might define the following number template for a video cable: “??####”. This means that the cable number will consist of six characters, beginning with two constants followed by four numbers, e.g.: VA0000.