Designations used in marking asynchronous electric motors and their decoding

In engines of series A, AO, A2, AO2 and A3, letter A means splash-proof design, AO — closed blown, the first digit after the letters is the serial number. The number after the first dash characterizes the standard size; the first digit in it indicates the size (notional number of the outer diameter of the stator core), the second - a number of notional length. The number after the second dash corresponds to the number of poles. For example, AO2-62-4 is an asynchronous three-phase electric motor in a closed design, of the second single series, sixth dimension, second length, four-pole. Electric motors of sizes 1-5 of the second series are produced only in a closed blown version, which increases their reliability: the service life of a low-power closed machine increases by 1.5-2 times compared to a protected one.

The general A, AO and A2, AO2 series motors of the basic design have a squirrel-cage rotor with an aluminum winding. A number of engine modifications were created on their basis.When designating modifications, a letter is added to the letter part for electric motors: with increased starting torque-P (for example, AOP2-62-4); with increased slip — C, for the textile industry — T, with a phase rotor — K.

Induction motors with increased starting torque are designed to drive mechanisms with heavy loads during the starting period. Increased slip motors are used for mechanisms with uneven shock loading and mechanisms with a high frequency of starting and reversing.

For general-purpose motors with an aluminum stator winding, the letter A is added to the end of the designation (for example, AO2-42-4A). For motors with several rotation speeds, all their values ​​​​are entered in the numbers characterizing the number of poles, separated by oblique lines: for example, AO-94-12/8/6/4-three-phase asynchronous motor of the AO series with 9 dimensions, 4- th length with 12, 8, 6 and 4 poles.

The letter L (eg AOL2-21-6) means that the body and shields are cast from aluminum alloy.

The designation of the standard size of a 4A series motor, for example, 4AH280M2UZ, is deciphered as follows: 4 — serial number of the series, A — motor type (asynchronous), H — protected (the absence of this sign means a closed blown version), 280 — the height of the axis of rotation (three or two digits), mm, S, M or L — installation size along the length of the bed, 2 (or 4, 6, 8, 10, 12) — the number of poles, UZ — climatic version ( U) and displacement category (3).

After the first letter A, there may be a second A (for example, 4AA63), which means that the frame and shields are made of aluminum alloy, or X is aluminum frame, cast iron shields; the absence of these marks indicates that the frame and shields are cast iron or steel.

When designating motors with a phase rotor, the letter K is placed, for example, 4ANK.

With the same dimensions of the frame, the stator core can have different lengths. In this case, when indicating the standard size after the letters S, M, JL and immediately after the rotation height, if these letters are missing, signs A (shorter core length) or B (longer length) are placed, for example 4A90LA8, 4A90LB8, 4A71A6, 4A71B6.

Climatic versions of the engines are indicated by the following letters:
Y — for temperate climates, CL — for cold climates, TV — for humid tropical climates, TC — for tropical dry climates, T — for both dry and humid tropical climates, O — for all land regions (general climate version) , M — for marine temperate cold climate, TM — for tropical marine climate,. OM — for unrestricted navigation area, B — for all land and sea areas.

Accommodation categories are indicated by numbers: 1 — for outdoor work, 2 — for rooms with relatively free access to air, 3 — for closed rooms where fluctuations in temperature, humidity, as well as exposure to sand and dust are significantly more - small than in the open air, 4 — for rooms with artificially controlled climatic conditions (for example, closed heated and ventilated production rooms), 5 — for work in rooms with high humidity (for example, unventilated and unheated underground rooms, rooms in which there may be prolonged presence of water or frequent condensation of moisture on the walls and ceiling).

GOST 17494-72 for electric cars establish the degree of protection of personnel from contact with conductive or moving parts in the machine and, in addition, from the ingress of solid foreign bodies and water.

Electric motors for general use are mainly produced in two degrees of protection: 1P23 (or IP22 for DC motors) and IP44: the first of them characterizes machines in a protected design, the second in a closed one.

Alphanumeric designation of the degree of protection consists of the Latin letters IP and two numbers. The first of these numbers characterizes the degree of protection of personnel from contact with conductive and rotating parts inside the machine, as well as the degree of protection of the machine itself from the penetration of solid foreign bodies into it; the second number is from water ingress into the machine.

In the designation AzP23, the first digit 2 indicates that the machine provides protection against possible contact of human fingers with conductive and moving parts and penetration of solid foreign bodies with a diameter of at least 12.5 mm. Number 3 indicates protection against rain falling on the machine at an angle of no more than 60 ° to the vertical, and in the designation IP22 the second number is from drops of water falling at an angle of no more than 15 ° to the vertical.

In the designation IP44, the first number 4 indicates the protection against contact of tools, wires and other similar objects with a thickness of more than 1 mm with conductive parts in the machine, as well as from entering objects with dimensions of at least 1 mm The second number 4 indicates protection against water splashes from every direction.