武田機電
LOHER低壓防爆電機 Ex nA Ex e Ex d(e)
Loher motors in Ex nA Regarding explosion protection, for Ex nA II motors, the risk of arcing and sparking or hot surfaces during normal operation is prevented with an appropriate motor design therefore guaranteeing the required degree of safety. Motors with type of protection "non sparking nA" are used in explosive atmospheres, whereby, this atmosphere may occur in a potentially hazardous quantity. These motors are assigned to equipment group II - Category 3G (this corresponds to Zone 2). Loher Ex nA II motors are certified and optimally adapted for use in hazardous Zone 2 according to EN 50014 and EN 50021 or EN 60079-0 and EN 60079-15. They are stamped with II 3 G Ex nA II according to EC Directive (94/9/EC). The EC Declaration of Conformity documents that these regulations have been complied with. What is worth noting: According to EN 60079-15:2005, a risk assessment must be made for all motors with rated voltages above 1 kV. Loher has successfully completed the type test for the stator and rotor according to EN 60079-15:2005. As a consequence, normally no additional measures are required up to 11 kV. With Loher motors, the complex purging process before the motor started can be eliminated. When required, Ex nA motors also fulfill regulations relating to dust explosion protection according to EN 50281-1-1 // EN 50281-1-2. They are then additionally designated and documented with an EC type test certificate if the motors are operated in an environment with conductive dust. For variable-speed drives (converter operation), a type test must be performed with the actual converter intended for the application.
Loher motors in Ex e The basic idea behind this type of protection against explosion is to avoid the generation of sparks and arcs or excessively high motor temperatures by applying a series of measures so that there is no possibility of ignition in the first place. In addition, a suitable monitoring device is always required that even under fault conditions (e.g. locked rotor) avoids any ignition. Motors with type of protection "increased safety e" are located in an explosive atmosphere, whereby, this atmosphere may occur in a potentially hazardous quantity. These motors are assigned to equipment group II - Category 2G (this corresponds to Zone 1). They guarantee a high degree of safety. Loher Ex e motors are certified and optimally adapted for use in hazardous zone 1 according to EN 50014 and EN 50019 or EN 60079-0 and EN 60079-7. They are stamped with II 2 G Ex e II according to the EC Directive (94/9/EC). An EC type test certificate guarantees that the regulations are always maintained. Ex e motors also fulfill - if required - the regulations relating to explosion dust protection according to EN 50281-1-1 // EN 50281-1-2 and are then correspondingly additionally type tested and documented with an EC type test certificate if the motor is to operate in an environment with conductive dust.
Loher motors in Ex d(e) Motors with this type of protection against explosion are designed so that a possible explosion remains restricted to the inside of the motor. This means that the enclosure must be able to withstand the pressure from an explosion. In order to define the hazard as a result of an explosive gas (in comparison to other degrees of protection), in addition to the ignition temperature, it is also necessary to specify the capability of an igniting flame to be transmitted through a narrow gap in the motor enclosure. This is realized by classifying them in explosion groups IIA, IIB, IIC. Motors with type of protection "flameproof enclosure d" are located in an explosive atmosphere, whereby this atmosphere may occur in a potentially hazardous quantity. These motors are assigned to equipment group II - Category 2G (this corresponds to Zone 1). They guarantee a high degree of safety.Loher Ex d(e) motors are certified and optimally adapted for use in hazardous Zone 1 according to EN 50014, EN 50018, EN 50019 or EN 60079-0, EN 60079-1 and EN 60079-7. They are stamped with III 2 G Ex d IIB, II 2 G Ex d IIC according to the EC Directive (94/9/EC). (When the terminal box is designed and constructed to comply with increased safety with II 2 G Ex de IIB, II 2 G Ex de IIC.) An EC type test certificate always guarantees that the regulations are maintained and complied with. Ex d(e) motors also fulfill - if required - the regulations relating to dust explosion protection according to EN 50281-1-1 // EN 50281-1-2 and are then correspondingly additionally type tested and documented with an EC type test certificate if the motor is to operated in an environment with conductive dust.
