Asynchronous explosion-proof electric motors with square-cage rotor AIM
series is made for operation from a three-phase alternating current network with 50 Hz – 60 Hz frequency, with explosion-proof marking 1ExdiallBT4 (1ExdllBT4 for motors without stator winding temperature sensor), operating in explosive areas (chemical, gas, oil-refining industries) according to SRARP 40.1 – 1.32-01 “Rules of the construction of electrical installations. Electrical equipment of special installations” and other requirements documents regulating the use of electrical equipment in explosive areas.
The line of these explosion-proof electric motors consists of 80, 90,100, 112, 132, 160, 180, 200, 225, 250, 280, 315 and 355 typical sizes, with poles quality 2, 4, 6, 8 and 10.
Installation-connection dimensions and technical specifications of the motors are given in the catalogue.
Nominal values of climatic factors for engines operating in a working state – according to GOST 15150 for ambient class products are U3, U2, HL2, T2.
Manufactoring of other ambient class motors according to GOST 15150 needs preliminary agreement with the manufacturer.
Table 1. Climatic category and placement category of electric motors (operational temperature and humidity).
||Operational temperature, C
||Maximum relative humidity, %
||100 at 25°С
||98 at 25 °С
||80 at 25 °С
||100 at 35 °С
||80 at 25 °С
||100at 25 °С
1 – outside;
2 – under the roof in the absence of direct solar exposure and atmospheric precipitation;
3 – inside, without artificial regulation of climatic conditions;
4 – inside, with artificial regulation of climatic conditions.
Y – moderate climate;
YHL – boreal climate;
T – tropical climate.
When the operating ambient temperature (air) exceeds to the value of above 40, nominal power of the motor must be reduced to 5 % with a rise in temperature for every 5 C. Maximum ambient temperature while operating the motor must not be higher than 60 C.
Nominal power is provided in a long-term operation mode at a temperature of 40 ° C and a height above sea level of not more than 1000 m, although they remain operational at an altitude above 1000 m to an altitude of 4,300 m above sea level, with a decrease in engine power.
When operating at an altitude of more than 1000 m to 4300 m, the load on the engine must be reduced according to Table 2.
Table 2 – Permissible load on the engine
|Height above sea level, m
|Power change coefficient, KN
– AIM are produced with the binding of capacities to the standard sizes according to GOST 183;
– 2АIМ are produced with the binding of capacities to standard sizes according to DIN 42673 и DIN 42677 (CENELEC).
Motors should be operated in S1 mode.
The motors, which are produced in a metal case, have the level of protection IP54 according to GOST 17494 (fan cover – IP20). Electric motors with rotation height from 80 mm to 355 mm, the motors in a cast-iron case are produced with the level of protection IP55. When ordering, the level of protection could be changed from IP54 to IP55 with a customer’s agreement.
The motors have the insulation system of the class of heat resistance F (temperature index 155C). In this case, the excess of the temperature of the stator windings over the ambient temperature of the engines, having a service factor of 1.15, is not more than 83 ° C, engines having a service factor of 1.1 – is not more than 90 ° С.
In the stator winding there are temperature sensors RTS (these are thermistors with a positive temperature coefficient of resistance). The electrical insulation of engines intended for operation in mines is level 1 according to GOST 24719 and is designed to operate at a high relative humidity of 100% (with condensation of moisture) and at a temperature of 35 ° C.
The motors correspond to the class I of protection from the electric shock in accordance with the requirements of c. 2.1 of GOST 12.2.007.0
According to the type of mounting according to GOST 2479 the motors are produces:
– on feet – IM1081 (B3)
– on feet with flange – IM2081 (B35)
– without feet with flange – IM3081 (B5)
When you order the motor with a mounting type IM3081 (B5) you should indicate the way of motor mounting.
The motors could have left as well as right directions of rotation. The direction could be changed just when the rotor is in quiescent state.
The motors correspond to the group of operating conditions M6 – vibration loads corresponding to the degree of rigidity 10a (frequency range 1-100 Hz maximum acceleration 1 g according to GOST 17516.1-90).
With manufacturer’s agreement motors with power from frequency-controlled converters can be manufactured (for this purpose you should fill the configuration data sheet).
The root-mean-square value of the vibration velocity of bearing supports does not exceed 2.8 mm / s.
The example of motor explosion protection marking
For AIM motors
I – Sign of the level of explosion protection for explosion-proof electrical equipment.
Ex – The engine complies with the standards for types of explosion protection.
d – Explosion proof enclosure.
IIB – Category of explosiveness of a mixture of gases and vapors with air.
T4 – The sign of the temperature class of electrical equipment (the chemical formula of hydrogen, which forms a combustible mixture with air)