Ventilator openings are designed to prevent liquids and solids from entering the machine from an angle of 0 to 15. Submersible enclosures are suitable for application where the equipment may be subject to submersion. This protection can make motor more life span and can running in suitable condition. The national electrical manufacturers association nema maintains a number of standards for electrical components. Cooling air is blown through the motor by a fan mounted on the shaft.
When this is a motor requirement, it must be specified with the order. Motor enclosure terminology a guide for product comparisons. The magnet is spun by a 3 phase ac motor with no rotor voltage 4. Aug 04, 2017 there are several specific types of electric motor enclosures available on the market, and they can be broken down into two basic types. Totally enclosed, fancooled tefc motors have an external fan which circulates outside air to the motor.
If an explosion does occur within the motor, hot gases. In addition, the type of enclosure affects the cooling of the motor. Nema enclosure types the national electrical manufacturers association nema maintains a number of standards for electrical components. These motors are typically known as jet pump motors, as they were originally designed for shallow well jet pumps. Class 8538 fusible full voltage type class h and k fuse clips, with motor logic ssolr replace with the voltage code ratings enclosure motor voltage starter voltage max. The degree of protection depends on the enclosure type. For more detailed and complete information, nema standards publication 2502003, enclosures for electrical equipment volts maximum. Section approval of the standard does not necessarily imply that all section members voted for its approval or participated in its development. In the bigger rotor motor b, very long endring fins are adopted as evident in fig. To protect motors, a certain enclosure or encapsulated windings and special bearing protection may be required.
The enclosure will also remain undamaged by the formation of ice on the enclosure. Enclosure class states the degree to which an electrical enclosure, such as a motor, is protected against the intrusion of solid objects and water. The adopted motor code together with the name plate data of the two prototypes are reported in table i. Fan cooled tefc, pipeventilated tepv, air over teao, nonventilated tenv, air to air teaac, water to air tewac, and. For example, you can find tefc motors that are ip44, ip54, ip55, ip56, etc. The motor lamination is totally closed in the stator housing and it is cooled by a flow of inner air with rotating inner fans, and the heat exchange is through the pipes or ribs or through water exchanger on the top. The totally enclosed nonventilated tenv type of enclosure has no external cooling, but uses an internal fan to circulate the air within the motor. Choose the right electric motors for hazardous locations. The type of motor enclosure you desire depends on where you plan to put your pump. The national electrical manufacturer association nema uses a standard rating system that defines the types of environments in which an electrical enclosure can be used, and frequently signifies a fixed enclosure s ability to withstand certain environmental. Understanding motor nameplate information nema vs iec standards course content the motor standards can be grouped into two major categories. A motor enclosure not only holds the motors components together, it also protects the internal components from moisture and contaminants. American market ingress protection ip ratings are developed by the european committee for electro technical standardization cenelec described iecen 60529, and specifies the environmental protection and enclosure provided. Ic 416 enclosure ip 44 ip 55 type gzo external surface cooling tefv cooling air is blown over the totally enclosed motor surface by an separately excited fan motor.
Nema ratings for enclosures nema enclosure ratings chart. Jul 11, 2019 the primary classification of motor or types of motor can be tabulated as shown below, history of motor in the year 1821 british scientist michael faraday explained the conversion of electrical energy into mechanical energy by placing a current carrying conductor in a magnetic field which resulted in the rotation of the conductor due to the. Equally tenv motors can be anywhere between ip20 and ip56. Introduction a motor enclosure not only holds the motors components together, it also protects the internal components from moisture and contaminants. This standards publication was developed by the nema enclosure section of the national electrical manufacturers association. Type description 7 intended for indoor use in locations classified as class i, groups a, b, c, or d, as defined in the national electrical code. Enclosure types and cooling motors are often exposed to damaging atmospheres such as excessive moisture, steam, salt air, abrasive or conducting dust, lint, chemical fumes, and combustible or explosive dust or gases. Architects are often asked to select a component that has a nema enclosure type. Nema enclosure types in nonhazardous locations, the specific enclosure types, their applications, and the environmental conditions they are designed to protect against, when completely and properly installed, are as follows. Uses soft magnet rotor that is magnetized by the application of current in the stator coils 3. Instead, the commutation of the windings of a bdc motor is done mechanically. The two digits indicate the protection against solid objects and water, respectively. Nema enclosure classifications are developed by nema and used in the u. Industrial and commercial duty iec motors tristate bearing.
Types of motor enclosures electrical engineering centre. Open enclosures permit cooling air to flow through the motor. Pdf end space heat transfer coefficient determination. It depend on our application and location when install a motor.
Type 1 enclosures constructed for indoor use to provide a degree of protection to personnel against access to hazardous parts and to provide a. Mcc ratings in addition to the various ratings of individual components used in motor control centers, the overall ratings of the motor control center must also be considered. The enclosures of electrical motors are standardized by nema national electrical manufacturers association as. Electrical electronic enclosure nema standard 250 engineers. The motor standards can be grouped into two major categories. Type 3r enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts. There are several specific types of electric motor enclosures available on the market, and they can be broken down into two basic types. The importance of motor enclosure type the snell group. When you are choosing a motor, you may be wondering what all the motor enclosure in the description mean. An odp enclosure can protect the motor s interior from water falling on top of the motor, but not from water coming from the sides. Applications for enclosure types type 1 generalpurpose enclosures suitable for generalpurpose indoor applications, where atmospheric conditions are normal. Industrial and commercial duty iec motors tri state bearing. Fan cooled tefc, pipeventilated tepv, air over teao. This elearning module provides a basic understanding of three phase induction motors.
This is the maximum voltage that can be applied to a motor control center. These motors are suitable for indoor use and clean atmospheres. An enclosure protects a motor from contaminants in the environment in which it is operating. The enclosure design will depend upon the specified conditions of pressure and time. Pdf end space heat transfer coefficient determination for. According to nema standard ics 182001 r2007, there are three different types of wiring. Ic 37 enclosure ip 44 ip 55 type gz double pipe ventilated tepv. American market ingress protection ip ratings are developed by the european committee for electro technical standardization cenelec described iecen 60529, and specifies the environmental protection and enclosure provided the table below can be used to convert from nema enclosure types to iec enclosure types. Electrical motor types classification and history of motor.
End space heat transfer coefficient determination for different induction motor enclosure types. I would like to take one step further and say expensive and cheap. It also provide a types of cooling system for a motor depend on their types of enclosure. Due to the cooling effects, these types of enclosures are not practical for large horsepower ratings. Tefc totally enclosed fan cooled, means for a type of motor which has a difference between inner and outer air for cooling. Designing a motor to contain an explosion is not a simple task, as it requires careful consideration of the strength of the materials used in the enclosure and the motor hardware. A segmented copper sleeve, called a commutator, resides on the axle of a bdc motor. In addition, the type of enclosure affects the motor. Section approval of the standard does not necessarily imply that all section. Voltage rating motor control centers are rated for 600 volts. Oct 26, 2017 if the fire pump will be inside a room, then a odp enclosure and nema 2 enclosure for the fire pump controller is sufficient, even with sprinklers installed. Nema enclosure types type 3s enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts. Cooling air is blown over the totally enclosed motor surface by a fan mounted on the shaft.
Understanding motor nameplate information nema vs iec. In neccec group installations, these devices must be applied per the appropriate rules which require the use of an upstream branchcircuit, shortcircuit protective device bcpd. The rotor has salient poles and a cage so that it starts like an induction motor, and runs like a synchronous motor. In north america, the national electric manufacturers association nema sets motor standards, including what should go on the nameplate nema standard mg 110. Designed for reasonably dry, clean, and well ventilated usually indoors areas. An odp enclosure can protect the motors interior from water falling on top of the motor, but not from water coming from the sides. Nema further subdivides motor control centers based on various wiring classes. If you place the wrong motor into a chemical plant, a disastrous explosion could occur.
Motor controllers with optional approvals for motor disconnect and group installation. Ventilation openings in shield andor frame prevents drops of liquid from falling into motor within up to 15 degree angle from vertical. Open enclosures permit cooling air to flow through the. An enclosure, according to the national electrical manufacturers association nema, is a surrounding case constructed to provide a degree of protection to personnel against incidental contact with the enclosed equipment and to provide a degree of protection to the enclosed equipment against specified environmental conditions. Utilizes cooling fins on all four quadrants of yoke and housings. In addition, the type of enclosure affects the motors cooling. Hazardous location enclosures class ii, group e, f or g. The pump models ssp, and sspc are mounted on standard cface 56j frame motors. Han 10es plug connector on terminal box with single locking latch cage clamp contacts on motor end asb. Enclosure types and cooling motors are often exposed to damaging atmospheres such as excessive moisture, steam, salt air, abrasive or conducting dust, lint. Two codes that define iec motor enclosures there are two codes that define iec motor enclosures. Generally speaking, there are three different types of. This is especially true for flange cface, dflange type motor mounts.
An enclosure that is selected to meet a specific rating and standard may not meet all requirements of your application and. The more common of these enclosure types are open machines. Nema designates certain enclosure types, and the degree of protection against environmental intrusion that each affords. Motors that require 50 and 60 hz operation of the same motor are nonnema defined motors and will be nameplated as such. Open drip proof odp enclosure open enclosures permit cooling air to flow through the motor. If the fire pump will be inside a room, then a odp enclosure and nema 2 enclosure for the fire pump controller is sufficient, even with sprinklers installed.
Each type specifies characteristics of an enclosure, but not, for example, a specific enclosure size. Type 3 enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against incidental contact with the enclosed equipment. Motor protection circuit breaker and motor circuit. Comparison chart nema ratings enclosure types the question in terms of which electrical enclosures are suitable for your application, environment and give enough protection to your equipment, but not overwhelming and make you overpay for it. Enclosures definitions and applications for enclosure types. Normally there are have two categories of enclosure,it is open and totally enclosed. Those enclosure types are listed below and are based on nema standards publication 2502003.
Comparison chart excellent nema electrical enclosures. Variable frequency operation motors are available for use on variable frequency inverters. For example, types 3, 4 and 6 are intended for outdoor. Open dripproof odp motors are equipped with open enclosures. Dripproof motors have open enclosures, suitable for indoor use and clean atmospheres. Enclosure class is expressed as ip followed by two digits see table. Classification of electric motors electrical knowhow. Different types of motor enclosure instrumentation and control. This type of motor is capable of delivering 100% torque down to 10 or 5% of base speed. Types of protection c, b en k will not being marked on the product, because of possible user mis interpretation with levels of protection c and b.
Selecting your motor enclosure american stainless pumps. Nema enclosure types the purpose of this document is to provide general information on the definitions of nema enclosure types to architects, engineers, installers, inspectors and other interested parties. There is no strict correlation between motor enclosure types and ip ratings. These enclosures serve as protection against falling dirt but are not dust tight. Motor protection circuit breaker and motor circuit protector. Note that higher numbers do not include the lowernumbered tests. At nema enclosures, our knowledge and experience in nema rated enclosures is so extensive, its in our name. The national electrical manufacturer association nema uses a standard rating system that defines the types of environments in which an electrical enclosure can be used, and frequently signifies a fixed enclosures ability to withstand certain environmental. The main purpose of motor enclosure is to provides protection from environment impacts such as rain,corrosive,rusty and many more in which motor installed.
Nema ratings for enclosures nema enclosure ratings chart 1. Other types of definite duty motors include wash down, hazardous. Enclosures are categorized as either open or totally enclosed, and there are different types of enclosures within each category. Enclosures are categorized as either open or totally enclosed, and there are. Different types of motor enclosure instrumentation and. One type of open enclosure is the open drip proof odp enclosure. In most cases, every available motor enclosure could work for a single. Nema designates certain enclosure types, and the degree of. Sep 15, 2015 some of the enclosure types are obvious.
705 705 651 1367 668 111 1169 1026 747 486 993 1519 179 1330 1562 917 1437 1254 805 1329 889 394 159 1421 1114 164 792 1115 178 282