A basic knowledge of motor:
Small three-phase asynchronous motor, usually including H80-315MM motor, its output, wide range of uses, in the total load on the power grid, its power consumption is about 40%. Popular in the early 1960s for the JO2 series motor, the series of motor power rating, installation size and common standards on the international market is different, in addition to the motor starting torque is low and the lack of noise control indicators, so now our country’s motor Y series motor. The motor is rugged, safe and therefore more widely used. However, some users of the motor annual damage rate of up to 5%, the reason most of them are improper selection, improper use, poor protection reasons. Therefore, the main purpose of this lecture is: to find the quality problems occurred in the use of the motor, properly resolved.
Small asynchronous motor system Small asynchronous motor can be divided into: basic series, derived series and special series. The basic series uses a wide range of production volume, is a universal motor, such as the Y series (IP44) small three-phase asynchronous motor. Derivative series in accordance with the different requirements of use, based on the basic series made some changes, and the other parts with the basic series of high versatility and a certain degree of unity. Derived from a series of electrical derivatives (such as high-efficiency motors, YX series), derived from the structure (such as winding rotor motor YR series), special environmental derivatives (flameproof motor, YB series), and several other. Special series with different general purpose, with special requirements and special protection conditions, such as YZ, YZR metallurgical and lifting asynchronous motor.
Motor Basics II:
Basic series of technical parameters 1, standard number JB / T9616-1996 2, the shell protection structure type Y series of small three-phase asynchronous motor basic series IP23, IP44 two kinds of shell protection grade. IP23 and IP44 meanings are as follows: IP — indicates the symbol of protection level, the following two digits are as follows: Level Requirement The first digit of IP23 can prevent fingers from touching and electrified or rotating parts in the case, Small solids with diameter greater than 12mm Enter the second digit No water spray with vertical 60 degrees or less No harmful effects on the motor IP44 The first digit prevents tools, wires, or similar in thickness greater than 1MM Objects that reach the live or rotating parts of the enclosure prevent ingress of small solid objects of more than 1 Mm in diameter but do not include vents that are blown or blown by outside fans and scuppers for enclosed motors that have Class 2 Protection of the second digital splash water in any direction on the motor, there should be no harmful effects. 3, the installation structure and type Y series motor installation structure, divided into the foot installation, with the foot with flange cover installation and a flange cover installation three. According to the three basic installation structure, the motor installation is divided into horizontal or vertical installation and shaft extension up or down, that is, B3, B35, B5, V1, V15 and other installation methods, the specific model check standard. 4, the cooling method Y series motor is basically by the ambient air to cooling.
IP23 motor uses the rotor blade on the end ring as the driving element. The surrounding cold air enters from the end cap and is pressurized by the fan blades to carry part of the rotor heat and then cool the stator winding end and core back. The heated air from the machine The middle of the shell is discharged outside the machine.
IP44 motor, the heat generated by the internal losses (iron loss, copper loss, mechanical loss) of the motor during operation is transmitted to the motor surface, and the surrounding air is continuously driven by the fan installed on the non-axial extension end to take away the above heat, To achieve the purpose of cooling the motor. 5, power level and installation size checklist. 6, the main performance indicators Some motors and other plants are more likely to short iron core, enameled wire fine, but the motor power and other performance indicators are in line with standard requirements. 7, Winding temperature rise Y series motors adopt Class B insulation, allowing winding temperature rise to 80K. Another class F insulation allows winding temperature rise to 115K. 8, operating conditions (1), the elevation does not allow more than 1,000 meters, the maximum ambient temperature does not exceed 40 ℃, the lowest temperature of -15 ℃. The wettest lunar month at the place of operation has an average maximum humidity of 90%, while the monthly average minimum temperature is not higher than 25 ℃. (2) The power supply voltage is 380V ± 5%, the frequency is 50HZ, the change does not exceed ± 1%, the imbalance of three-phase current no-load does not exceed 10%, and the load does not exceed 5%. No-load current is generally 30-55% of the load current.
Three basic motor:
Nameplate data: General motor nameplate Content Type: VOLT: 380V Frequency (HZ): 50HZ Connection (CONN.) Under normal circumstances 3KW and below the motor is the star connection, 3KW above the motor is the angle connection . Power: SER.NO. Protection Class (ENCL) Insulation Class (INS.CLASS) Applicable Standard: JB / T9616-1996 Noise [LW dB (A)] R / MIN Rated Current (AMP) DATE WORKING DUTY WEIGHT (WGT) SPECIAL ELECTRICAL MACHINES OTHER THAN THE INDICATORS THREE-PHASE INDUCTION MOTOR THREE PHASE INDUCTION MOTOR SERVICE FACTOR (S.F.) CURRENT UNDER SERVICE FACTOR .A.) Efficiency at 100% load EFF. (100% FL) Efficiency at 75% load EFF. (75% FL) Ambient temperature limit MAX. AMB shaft end bearing type BRGS. P. E non-shaft end bearing type O. P. E. The user’s part number (PART.NO)
Three basic motor knowledge
A basic knowledge of motor: