This standard specifies the naming method for lamp caps and lamp holders for electric light sources.
2. Symbol system
One of the purposes of this symbol system is to make each designated symbol short, easy to read, and to help indicate its purpose. The symbol system is composed of letters, numbers, and symbols, each of which has its own meaning. Only one symbol should be used for each specific lamp holder and lamp holder. This symbol system cannot be used to identify the materials used for lamp holders. The parts of a symbol system should be directly connected together without gaps or other separators.
The complete symbol of the lamp base and lamp holder adopts the following form.
Lamp symbol: (a)(b)(c)-(d)/(e)×(f)
Lampholder symbol: (a)(b)(c)-(d)
Note: Abbreviated lamp head symbols can be used, but such abbreviated symbols must not cause misunderstanding.
The symbol in front of the slash in the lamp head symbol indicates the content that is very important for the interchangeability in the response lamp holder with a certain lamp head. This particular part of the symbol is the same for the lamp cap and the lamp holder used. The part after the slash in the lamp cap symbol (if this part exists) indicates some important dimensions of the lamp cap, but these dimensions are not a necessary part of the interchange requirements of the lamp in the lamp holder. However, this size is very important for the common interchangeability of lamp caps of different sources mounted on lamps of the same model.
Note: The terminology of IEC is opposite to the North American terminology, and the contact part and fixed part of the headless lamp are called 'lamp end'.
3. Basic symbols
Part (a) of the symbol consists of one or more capital letters, indicating the type of lamp cap. Although the following letters indicate the lamp cap, they have similar meanings for the lamp holder.
B--Bayonet lamp holder;
BA-bayonet lamp cap, originally used for car lights;
BM-bayonet lamp holder for miner's lamp;
E-- (Edison) screw cap;
F--Lamp head with an outlet;
The lowercase letters after the letter F indicate different forms of contacts, for example:
a--indicates cylindrical pins;
b--Indicates the pin with groove;
c--Indicates the pin of special shape;
G--Two or more protruding contacts, such as pins or terminals;
K--lamp head with wire connection;
P--pre-focused lamp head;
R--lamp head with concave contact;
S--Shell-type lamp holder--The lamp holder is not fixed by the protruding parts in the lamp holder
SV--Shell-type lamp cap with tapered end (V-shaped);
T--lamp for telephone;
W--- means the lamp end, the electrical contact between the lamp and the lamp holder is directly completed by the lead wire located on the surface of the lamp end, and the glass part (or other insulating material part) of the lamp end is indispensable for the installation of the lamp in the lamp holder Less. For a single lamp cap that can replace the entire lamp end and symbolize the same interchangeability requirements, it can also be represented by a symbol;
Note: Some of the earlier symbols were shaped like ?-shaped objects, which led to the use of the letter symbol 'W'.
E27--Spiral lamp holder;
Fa4--Lamp head with a cylindrical pin contact.
X--If according to the above regulations, a symbol can not be used to represent a lamp head, then this type of lamp head is expressed by a capital X plus a series of numbers.
For example: X511--glass lamp end with two independent metal wings.
Modification method Ⅰ
If the additional characteristics of a certain lamp cap are included in the above capital letters and can be represented by the additional capital letters, then the letter that represents the most important meaning in the entire letter combination should be ranked first.
For example: PK22s----prefocused lamp head with wire connection.
Modification method Ⅱ
Lamp caps whose characteristics are consistent with the provisions of this standard may use symbols that have been used in lamp caps. If the lamp cap is not (or not fully) interchangeable in terms of electrical or mechanical requirements, capital letters X, Y, Z or U, or a combination of more than two such letters, shall be added after the basic symbol of the lamp cap.