Aislamiento Motores Eléctricos

Insulation Class

Standards established by the National Electrical Manufacturers
Association (NEMA) to meet motor temperature requirements
found in different operating environments. The combination of
an ambient temperature of 40°C and allowed temperature rise
equals the maximum winding temperature of a motor. A margin
is also allowed to provide for a point at the center of the motor’swindings where the temperature is higher.

Insulator

A material with a high resistance to the flow of electrons.
Plastic, rubber, glass, and mica are examples of materials that
are good insulators.

International
Electrotechnical
Commission (IEC)

An organization based in Geneva, Switzerland, with over 50
member nations. IEC writes standards for electrical and
electronic equipment andpractices.

Interrupting Rating

The maximum level of fault current that a circuit breaker or fuse
can interrupt. The interrupting rating is also called the ampere
interrupting capacity (AIC).

Inverter

A device that converts direct current to alternating current.
Inverter is also used as a synonym for an AC drive even though
the AC drive usually includes other circuits.
Inverter650 VDC

ISO

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Control Logic

IGBT

3Ø Motor

A federation of standards organizations from over 100 countries
that develops voluntary standards for business, science, and
technology. The official name is Organization Internationale de
Normalisation. The name ISO is from the Greek word “isos”
which means equal.

Isolation Transformer

A transformer used to limit thetransfer of electrical noise from
one circuit to another.

Joule

The basic unit of electrical energy. 1 Joule is equal to 1 wattsecond or the amount of energy transferred in one second
when the power is one watt.

Knockout

A place in an enclosure where a piece of the enclosure can be
removed to allow for cabling.

Ladder Logic

A method of programming a programmable logic controller thatuses symbols that evolved from the diagrams used with control
relays.

Limit Switch

A type of sensing switch that opens or closes its contacts
when its actuator is moved by an object.

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Limit Switch Positions

The following terms identify the operating positions of a limit
switch.

Load-Break Switch

A switch designed to safely interrupt load current.

Load Center

Anindustry term used to identify a lighting and appliance
panelboard when it is used in certain (usually residential)
applications.

Local Area Network (LAN)

A communication system that interconnects intelligent devices
within a limited area, but may also connect other networks for
larger-scale communication.

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Main Breaker

The circuit breaker in a load center, panelboard,switchboard, or
switchgear that is connected to the source of supply.

Main Lug Only

A designation given to a load center or panelboard to indicate
that it does not include a main breaker.

MCM

Thousands of circular mils. A method for designating the crosssectional area of a conductor; especially conductors larger than
AWG 4/0 (four aught). One mill is equal to 1/1000 of an inch.
Circularmil area is the diameter (in mils) of a circular conductor
squared. 1 MCM is 1000 circular mils (also shown as 1kcmil).

Metric Unit Prefix

A prefix added to a unit of measure to increase or decrease the
size of that unit of measure. For example, the metric unit prefix
kilo can be added to meter to form a unit of length (kilometer)
equal to 1000 meters. Metric unit prefixes are associatedwith
powers of ten.

Microprocessor

The integrated circuit or chip that contains the central processor
unit.

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Molded Case
Circuit Breaker

A circuit breaker enclosed in an insulated housing. The housing
is normally made of molded plastic.

Molded Case Switch

A switch enclosed in an insulated housing similar to that of a
molded case circuit breaker.

Motor

A device...