Eaton Industrial Switchgear - General Information

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2010 CA08103002Z-EN
Switchgear for North America 22/9
These devices are of a rugged design
and have larger insulating clearances
than other switching devices (for
301 to 600 V: 1 inch = 25.4 mm air
distance and 2 inches = 50.8 mm
creepage distance).
In power distribution equipment
(switchgear, switchboards, panel-
boards), only these devices must be
used for power supply and tap-off. In
addition, these components are also
used, for example, as main switches or
circuit breakers in motor and other
load circuits in industrial control
systems.
Testing of these devices is specially
stringent, with running production
being subject to regular checks by test
authority inspectors. The type tests for
UL- and CSA-approved circuit
breakers are among the world’s
strictest. Eaton’s NA circuit breakers
have passed all of these tests.
Industrial control equipment
These include, for example, devices
to UL 508, CSA-C22.2 No. 14-05:
• Contactors.
• Contactor relays.
• Overload relays.
• Motor protective circuit breaker.
• Cam switch.
• Pilot devices.
• Electronic devices and systems.
• User-programmable PLCs
These devices have smaller physical
dimensions and the insulating
clearances are not as great as those of
power distribution devices. Here, too,
running production is monitored by
test authority inspectors, but the
inspection requirements are not as
extensive as those for circuit breakers.
This industrial control equipment is
used mainly in industrial control
panels, motor circuits and consumer
circuits of all types, in motor control
centers (MCC) and in power distribu-
tion systems. In industrial control
panels, it can be combined directly
with power distribution devices, for
example with circuit breakers as main
switches or in a motor feeder.
Circuit types in North America
In North America, main circuits are
classified into “feeder circuits”1) and
“branch circuits”2). In feeder circuits,
large clearances and creepage
distances are required, for example
according to UL 489. The boundary
between these two circuit types is the
“branch circuit protective device
(BCPD)”3), which are required to have
large clearances and creepage
distances at least on their feeder side.
Typical BCPDs are circuit breakers
NZM…-NA, PKZM4…-CB, FAZ…-NA,
and FAZ…-RT, and fuses. In North
America, circuit breakers must be
markedwith their conduction direction
(LINE or LOAD) unless they are
approved for both conduction
directions. The circuit breakers must
then be fed only from above and the
specified infeed side must be marked
“LINE”. The Eaton circuit breakers do
not have this limitation. We often
receive inquiries about this, even
though it is stated in the technical
data. As BCPDs, motor starters of
UL 508 Types E and F can be used
only for individual motors, not for any
other load type. In motor control
centers (MCC) the control voltage is
often generated per withdrawable
unit.
Ratings data for industrial
switchgear
Note that the IEC/EN rating data on
devices or in this catalog must not be
used for selecting devices for use in
North America. Use only the approved
data. As with the IEC and European
standards, which define utilization
categories for l.v. switchgear, US and
Canadian standards define “duty
types” for various types of switched
loads. The type of load for each duty
type is indicated on the device’s
ratings plate or in its technical
specifications and defines is
application purpose. The following
table provides an overview of these
assignments:
Duty type
Contactors
In North America, Contactors are
classified as industrial control
equipment according to UL 508 and
CSA-C 22-2 No. 14-05). For the North
American market, contactors must
have so-called “NEMA-sizes”4),
unless they are used for switching
motors, for which orders will specify
ratings in HP. For the NEMA-sizes,
corresponding HP motor ratings and
continuous thermal currents are
assigned to all North American
standard voltages.
Chapters 5 and 8 of this catalog list
the contactors and motor starters with
the HP ratings approved for North
America. The table on a Page 5/84
provides an overview of the NEMA
sizes in relation to the HP ratings and
continuous currents.
Combination “contactor and
overload relay” (“Non
Combination Motor Starter”)
First of all, it is important to know that
when North American customers
speak of “non-combination motor
starters” they mean what in Europe is
referred to as a “contactor and over-
current relay” combination and will
give the same ordering information as
for contactors. Complete contactor
and overcurrent relay combinations
can be assembled as per page 8/30. In
addition, a short-circuit protection
device, i.e. a fuse or circuit-breaker is
required. The highest permissible
rating for this protective device is
given in each case in this catalog.
Motor starters
(“Combination Motor Starters“)
The European-type motor starter that
contains all devices for short-circuit
protection, overload protection and
operational switching of the motor
(such as circuit-breaker, contactor
and overload relay), is called
“combination motor starter” in North
America. This type of motor starter
must be engineered like a small
control system complete with all
associated individual devices. The
contactor and overload relay are
selected as described on page 8/xx.
With its devices, Eaton offers different
versions for electrical, and to some
extent also for mechanical connection
of the motor starters’ components. The
most convenient connectionmethod is
provided by the tool-less plug connec-
tion wiring kits. All connection
methods with wires or elements of
different types are approved for North
America. This also goes for surface
mounting the motor starters on busbar
adapters of the SASY 60i system.
IEC/EN motor protective circuit
breakers
In North America, motor-protective
circuit breakers can not be used
irrespective of make, as is customary
in IEC and EN standard systems.
According to current US and Canadian
standards, these devices are
classified merely as “manual motor
controllers” or “manual motor
protectors”. These devices are
subject to the special conditions
described below, which must be
observed.
The integrated short-circuit protection
function and the isolating functions of
these motor-protective circuit
breakers is not recognized in North
America. According to UL 508 and
CSA C 22.2 No. 14-05, approved motor-
protective circuit breakers must be
protected against short circuits with
UL- or CSA-approved circuit breakers
or fuses. In the event of a short-circuit,
the motor-protective circuit-breaker’s
short-circuit release will, of course,
also trip.
The additional short-circuit protective
device can protect individual motor
starters or – if approved for use in
“group installations” – a group of
motor starters. Motor-protective
circuit breakers PKZM0, PKZM4 and
PKE are additionally approved as
“tap conductor protectors”.
Motor protective circuit breakers
PKZ, PKE (Chapter 7)
In North America, these devices are
industrial control equipment to UL 508
and CSA-C 22.2 No. 14-05) and are
used as manually operated motor
starters in controllers or separately as
1The “General Use” group corresponds with IEC/EN Category AC-1.
Load marking on the
apparatus/device
1) Motors Horsepower (HP)
2) Coils
(in auxiliary and control circuits)
Coils: Volts, Frequency Control Circuit
Contacts: Standard Pilot Duty or Heavy Pilot
Duty.
3) Resistance (heating) Amperes, resistance only
4) Incandescent lamps Amperes or Watts, Tungsten
5) Ballast
(electric discharge lamps)
Amperes, ballast (A, reactors)
6) General Use1 Amperes (A)
Notes
1) In NA, the term “feeder circuits” is used in the widest sense
2) Feeder circuits
3) BCPD = branch circuit protective device
4) NEMA = National Electrical Manufacturers Association (USA,