Other letters and numbers are used with these basic letters to further identify the cable and complete the designation. Common markings of a power sys- tem for successive cables from a distribution switch- board to load would be as follows: feeders, FB-411; main,   l-FB-411;   submain,   1-FB-411A;   branch, 1-FB-411A1;  and  sub-branch,  l-FB-411-A1A.  The feeder  number  411  in  these  examples  shows  the system voltage. The feeder numbers for a 117- or 120-volt system range from 100 to 190; for a 220-volt system, from 200 to 299; and for a 450-volt system, from 400 to 499. The exact designation for each cable is shown on the ship’s electrical wiring prints. NEW  CABLE  TAG  SYSTEM.—The   new system consists of three parts in sequence; source, voltage, and service, and where practical, destination. These parts are separated by hyphens. The following letters are used to designate the different services: C  Interior  communication D  Degaussing G   Fire   control K   Control   power L Ship’s service lighting N  Navigational  lighting P  Ship's  service  power R  Electronics CP  Casualty  power EL  Emergency  lighting EP  Emergency  power FL  Night  flight  lights MC  Coolant  pump  power MS  Minesweeping PP  Propulsion  power SF Special frequency power Voltages below 100 are designated by the actual voltage; for example, 24 for a 24-volt circuit. For voltages above 100, the number 1 shows voltages between  100  and  199;  2,  voltages  between  200  and 299; 4, voltages between 400 and 499, and so on. For a three-wire (120/240) dc system or a three-wire, three-phase system, the number shows the higher voltage. The  destination  of  cable  beyond  panels  and switchboards is not designated except that each circuit alternately receives a letter, a number, a letter, and a number progressively every time it is fused. The destination  of  power  cables  to  power-consuming equipment is not designated except that each cable to such  equipment  receives  a  single-letter  alphabetical designation beginning with the letter A. Where two cables of the same power or lighting circuit  are  connected  in  a  distribution  panel  or terminal box, the circuit classification is not changed. However, the cable markings have a suffix number in parentheses  indicating  the  section.  For  example, figure 6-1 shows that (4-168-1)-4P-A(1) identifies a 450-volt  power  cable  supplied  from  a  power distribution panel on the fourth deck at frame 168 starboard. The letter A shows that this is the first cable from the panel and the (1) shows that it is the first section of a power main with more than one section. The   power   cables   between   generators   and switchboards  are  labeled  according  to  the  generator designation. When only one generator supplies a switchboard, the generator will have the same number as  the  switchboard  plus  the  letter  G.  Thus,  1SG identifies  one  ship’s  service  generator  that  supplies the number 1 ship’s service switchboard. When more than   one   ship’s   service   generator   supplies   a switchboard, the first generator determined according to the general rule for numbering machinery will have the  letter  A  immediately  following  the  designation. The  second  generator  that  supplies  the  same switchboard will have the letter B. This procedure is continued   for   all   generators   that   supply   the switchboard, and then is repeated for succeeding switchboards. Thus, 1SGA and 1SGB identify two service   generators   that   supply   ship’s   service switchboard  1S. Phase and Polarity Markings Phase and polarity in ac and dc electrical systems are designated by a wiring color code as shown in 6-3