Electric motors classification

There are a number of electric motor types available. These motors are classified by the National Electrical Manufacturers Association (NEMA). These electric motor classifications are presented in the NEMA standards [7]. 

Figure 3-8 shows a graphic breakdown of the various electric motors available [8]. The outline in Figure 3-8 is based on an electrical classification. Besides their classification, NEM.A also classified electric motors according to... 

Valve actuators may be classified broadly as directional, such as solenoids and electric motors force-balanced, such as spring-loaded diaphragms, and position-balanced, such as valve positioners. On the basis of this classification, Close (C7) describes the important types of... 

Electrical cable schedule Voltage drop calculations Electrical area classification Electrical instrument interface drawings Underground electrical cable and cable trench arrangement Electrical equipment layout drawings Motor control center and power layout Load and short-circuit analysis VSDs configuration Plant lighting plan... 

The efficiency is set by the pump manufacturer when the final pump selection is made. It is usually based on their shop tests for the same model and size pumps. The pump efficiency can vary between 10% and 80%. Pump electric motor specifications require mechanical and electrical requirements. Motors can vary in size depending upon power, speed (RPM), frame size, area classification, orientation, service factor and type of enclosure (e.g. totally enclosed fan closure). 

Motor types and classifications are followed by a brief guide to motor selection, the essentials of picking the right motor for either a new or replacement application. Following this appUcation guide are discussions of two of the more practical concerns that face the electric motor user troubleshooting and energy efficiency. 

After an area classification has been established, then anelectrical equipment, instruments, and wiring must adhere to that classification. Therefore, some motor enclosure types would not be electrically acceptable for specific area classifications. 

Energy Efficient (EE) Motor Designs, 628 NEMA Design Classifications, 630 Classification According to Size, 630 Hazard Classifications Fire and Explosion, 631 Electrical Classification for Safety in Plant Layout, 647 Motor Enclosures, 649 ... 

What electrical classification would be specified for an area that has Classes I and II, Groups A and E, and Divisions 1 and 2 motors ... 

Motors, electrical components, and electrical installations shall be suitable for the area classification (class, group, division, or zone) specified by the purchaser and shall meet the requirements of local codes (such as NFPA 70, Articles 500,501, and 502) specified by the purchaser. 

Classification of Motors. Motor and control selection is strongly influenced by the ambient conditions under which they will be operating. The National Electric Manufacturers Association has classified motors according to mechanical features, particularly cooling methods as related to surrounding conditions ... 

For Case 2, each DVP requires 72.66 kWh of electricity, and operating cost savings due to this modification are US 257 801/year. Installed cost of two DVPs, based on vendor quotation, is US 400 000. So, payback period for this retrofit modification is 1.6 years. Thus, replacing the existing SJEs by DVPs is attractive for low capacities and non-hazardous applications such as a steam turbine s surface condenser vacuum system. DVPs are efficient, they require less electricity and so modification required at the substation is minimal. They are very compact and can be installed at ground level or on elevated platforms. Depending on the area classification of their location, explosion-proof motors may be required. 

In order to gain a clear picture of available drive solutions related to the actual type of conveyor, a conveyor classification system has been estabhshed. Conveyors, in general, can be classified according to several parameters such as application, length, conveying capacity, hft, kind of conveyor, and required drive system power. Looking from the electric drives system perspective, the required power and speed to turn the drive pulley and run the conveyor belt are the most relevant parameters. These parameters directly translate to the dimensioning of the motors, frequency converters, and power transmission equipment. Therefore, ABB have... 

The classification adopted here distinguishes motor vehicles into HEV and battery electric vehicle (BEV). For an easier reference, we mention for each hybrid vehicle its classification according to the level of hybridization, therefore highlighting mild HEVs and full HEVs, and the possibility of external recharge (plug-in HEV (PHEV)). In the section devoted to BEVs, we also included extended-range electric vehicles (EREVs). A section has also been devoted to microcars powered by lithium-ion batteries. 

Second, the discussions will be focused mainly on instrumentation and control parts. The specifics concerning other electrical equipment such as motors, etc. will not be covered unless called for as part of instrumentation discussions. In general, the guiding factors for EAC, hence hazardous area classification, shall include but not be limited to the following ... 

Among the ANSI standards is the National Electrical Code (NEC) which is directed at the elimination or control of electrical hazards. It defines the classification of areas according to the degree of hazard possibly foimd in the atmosphere and prescribes wiring methods, grounding, control, etc. These factors are important in motor selection. The NEC is a product of the National Fire Protection Association (NFPA). 

Electrical engineering 1116 plot plan is used to produce area classification drawings, to locate switchgear and the incoming sut tation and motor control center, to route cables, and to estimate bulk mato ials. 

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