Eaton Industrial Switchgear - General Information

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2010 CA08103002Z-EN
22/14 Switchgear for North America
protective devices. Overload protec-
tion of a single, directly connected
motor can be provided directly by the
frequency. For drives with several
motors and bypass circuits the motors
must be individually overload-
protected with overload relays.
The frequency inverters are used in
branch circuits. They can be used with
three-phase rated operating voltages
of up to 480Y/277 V, 50/60 Hz. Because
of their suppressor circuit, solidly
grounded star networks with neutral
conductor are always required.
Radio interference suppression
measures (EMC) in frequency-
controlled power drive systems (PDS)
are not specified in the North Amer-
ican standards. To ensure interfer-
ence-free operation, the EMC
measures laid out in IEC/EN 81600-3
should be carried out for machines
and plants for export to North America.
Control relays easyRelay
and MFD silver
Electronic control relays easyRelay
and multi-function displays MFD-Titan
have all UL 508 and CSA-C22.2 No.142
approvals. They are also approved
to CSA (Class 1, Div. 2) for use in
hazardous locations to CSA-C22.2
No. 213-M1987(R2008)1).
All technical details for the North
American market in this catalog, in the
installation instructions and in the
manuals are also given in American
units, such as inches, lb, and degrees
Fahrenheit. The relay data are given in
pilot duties B300, R300, and
make/break. The operational DC
voltage of 24 V is also the common
voltage for electronic components and
systems in North America.
easyRelay and MFD-Titan are
programmed in programming
language ladder diagram. The
easySoft software is also capable of
representing North American ANSI
contact sequences.
Control relays easyRelay and multi-
function displays MFD-Titan are
therefore fully equipped as control
components/systems for the North
American market.
Protection types for enclosures
(degree of protection)
• The binding design and degree of
protection requirements for enclo-
sures for the USA are defined in
NEC = NFPA 70, in UL 508(A) and in
UL 50(E). For Canada they are
specified in CSA-22.2 No. 14-05
and in CSA-C 22.2 No. 94. The
degrees of protection are given as
NEMA types or as identical
UL/CSA types. Because the
UL/CSA types must be third-party
certified, they have largely super-
ceded the NEMA types. Many
inspectors demand UL/CSA types.
Where products with third-party
certified UL/CSA types are avail-
able, they should be used in prefer-
ence.
• The enclosures used by Eaton are
accepted for use in North America,
since they are approved with
UL/CSA types and meet the
requirements regarding contact
protection, corrosion protection
and ingress protection against
solids and liquids. See the informa-
tion about degree of protection on
the selection pages or in the tech-
nical specifications for the product
groups.
• The IEC/EN standard ingress
protection (IP) types include
protection against ingress of solids
and water. The comparable stan-
dards in Canada and the USA go
further, also covering protection
against ingress of oil and coolant,
and corrosion protection of the
enclosure; they therefore also
define its place of installation. The
table on a Page 22/xx ((17/18))
provides an overview of the
requirements in Canada and the
USA and a comparison with the
IP ratings.
• IP protection type information has
no relevance for use in North
America and can not replace
missing information about
NEMA/UL/CSA types. The
NEMA/UL/CSA types cover the
corresponding IP ratings but not
the other way round.
When exporting to North America,
particular attention must be paid to the
selection and implementation of the
correct degree of protection for
enclosures and installed apparatus.
The inspectors are known to check
very thoroughly for adherence to the
degrees of protection. In almost every
case, plants fail the inspection on this
aspect and must be rectified. This
results in lost time and additional
costs. Always choose enclosures with
the right degree of protection from the
start. Every opening subsequently
made in an enclosure puts its degree
of protection into question. The degree
of protection remains intact only when
each of these enclosures is sealed
again to the same degree. This can be
done, for example, by installing a
control circuit device or switch handle
with the same or a higher degree of
protection. Likewise, all openings that
are not immediately apparent because
they are hidden by other components
must be sealed. In most cases the
assembly personnel knows exactly
where work was performed with less
than 100 percent accuracy. Hoping
that this will not be noticed will usually
result in severe problems. To obtain
acceptance, these locations will later
have to be improved at great cost.
Improvements carried out at the
customer’s site are specially expen-
sive. Here, too, it should be remem-
bered that this work has to often be
performed by a North American
vendor and can not be carried out by
the manufacturer, who can then, at
best, take on the role of supervisor.
Sheet-steel enclosures and
installation technique
Sheet steel enclosures can be used for
all types of controllers. In North
America, and specially in power distri-
bution systems cables are commonly
laid in metal conduits. Into these
conduits, individual strands, not whole
cables, are laid. The conduits are
bolted together along their entire
length to act as continuous grounding
conductor. They are connected to the
enclosure flanges with suitable metal
glands. Enclosures with metal flanges
ensure an uninterrupted conducting
connection between incoming and
outgoing conduits, so that the enclo-
sures are included in the grounding
measure. Sheet steel enclosures with
metal or insulating flanges are also
suitable for connecting plastic
conduits and cables, which are
connected with commercial glands.
In this configuration, protective
grounding must be provided with a
ground conductor routed with the
cabling. This cable routing type has
established itself in many modern
installations and is today the preferred
choice, for example for machines. On
machines, only the input wiring to the
main switch is often installed with
metal conduits. Regarding the configu-
ration and space utilization of cable
trays, cable ducts and wiring ducts in
control panels, the limitations imposed
by the Electrical Codes must be
observed. The permissible space
utilization lies some way below that
usually specified by the IEC/EN stan-
dards. Inspectors usually investigate
this aspect in great detail. Where
cable trays and ducts are secured to
the building, extensive regulations of
the Electrical Codes must be observed.
Consistent grounding of all compo-
nents that must be included in the
grounding system will be thoroughly
inspected and objections are not
infrequent. The required grounding
conductor cross-sections must be
adhered to under all circumstances.
Another important aspect is the
protection of the insulation of
electrical cables where the cables are
routed through openings or are
exposed to movement during machine
operation (for example trailing cables).
Cables that are mechanically
protected in IEC/EN installations must,
of course, also be protected in plants
destined for export to North America.
The cables as well as all materials
used for routing and securing them
must be verifiably approved. Always
observe the installation and dimen-
sioning instructions of the Electrical
Codes.
Wall-mounting enclosures CS
Eaton now supplies a new enclosure
systemwith approvals for the USA and
Canada. Wall-mounted enclosures
in 45 enclosure sizes ranging from
250 × 200 × 150 mm (h × w × d) to
1200 × 800 × 300 mm are available. The
smaller enclosures are ideal for
enclosing individual devices or small
combinations, such as motor-starter
combinations or frequency inverters
complete with the additionally
required components. The larger
enclosures are suitable for
constructing small to medium-sized
machine controllers. It is advisable,
wherever possible to fix the enclo-
sures to the machine. This has the
added advantage that the machine
can be delivered ready for connection
and fully function-tested. If the enclo-
sures and installation are mounted on
the building, the extensive installation
regulations of the Electrical Codes
must be observed. The enclosures
have a high degree of protection
(IP65 UL/CSA Types 1 and 12, indoor
use only). The surrounding rain
channel profile offers protection
against the ingress of liquid such as
water or oil as well as dirt when the
door is opened. A powder-coated
textured surface provides abrasion-
resistant corrosion protection. The
enclosures feature galvanized sheet
steel mounting plates. Sheet steel
bottom plates for self-assembly are
available. The enclosure can be turned
through 180° for cable entry from
above or below.
Insulated enclosures CI-...-NA
Enclosures CI-…-NA fulfil the statu-
tory North American requirements for
the construction and degree of protec-
tion, which is laid out in UL 508(A) for
the USA and in CSA-C22.2 No. 14-05 for
Canada. They are therefore suitable
for enclosing motor starters and
miniature and small controllers for
installations and machinery. With their
complete corrosion-resistance they
are ideally suited for humid or corro-
sive environments. The enclosures are
suitable for the connection of cables
and both metal and plastic conduits,
which are connected with commercial
screwed glands. Because the “total
insulation” that Eaton offers for its
enclosures is not recognized for
insulating enclosures in the USA and
Canada, the enclosures must be
grounded according to the enclosed
installation instructions.
Enclosures CI-...-NA are approved
both with and without insulated
flanges. For the full range of CI
enclosures with UL/CSA approvals
see Chapter 20.
Busbar systems SASY60i
Busbar systems are an essential part
of IEC/EN installations and of modern
control systems. In North America
they are still relatively new. There,
power distribution to switching and
protective devices is frequently still
implemented using power distribution
blocks, which are less well known in
the rest of the world. In 2007, when
Moeller began to introduce the busbar
system SASY 60i, the system’s compo-
nents received only approvals as UL
Recognized Components and CSA
Certified Components. In the mean-
time, most of the system’s key compo-
nents are approved as UL Listed and
CSA Certified Components – see the
markings on the selection pages. This
was an important step, as Listed
Components no longer have to be
included at additional cost into the
certification reports for switchgear
systems. In the next edition of UL 508A
the busbar system are expected to
also be included in “Component
Requirements” SA1, Table SA1.1.
Initially, the busbars were approved
only for peak loads of 1000 A/inch² or
1.55 A/cm², which is about half of the
load capability according to IEC/EN. In
the meantime, the busbars have been
tested and approved with IEC/EN
loads. This was a major step for
machine and panel builders that want
to supply world-market machines and
control panels.
Notes
1) Non-Incendive Electrical Equipment for Use in Class I, Division 2 Hazardous
Locations]