Load Centers

LOAD CENTERS
1
Load Centers
General Description
Murray
Load Centers—
LC2040B1200
LC002GS
the industry standard of highest
quality…designed to complement the
Murray line of Circuit Breakers.
Load centers are used for the protection and
distribution of loads in residential, commercial
and light industrial applications operating at 240
volts AC max. Load centers subdivide power
into branch circuits serving a variety of small
loads. They provide a switching and protective
function for these load circuits. Typical loads
are lighting, appliance, heating and small motor
branch circuits.
Murray load centers feature a new split neutral
design in all 1ø main lug and main breaker models from 100 Amp, 12 circuit through 225 Amp,
42 circuit. For service entrance applications, use
both bars for neutral and ground conductors.
For non-service entrance applications, use insulated bar for neutral conductors and uninsulated
bar for ground conductors.
Load centers are often referred to as service
panels, circuit breaker panels, or several other
names, however, they are officially known
as panelboards.
60 Amp 2 circuit load center, available in
indoor enclosure, surface and flush, and
outdoor surface enclosure.
200 Amp 1ø main breaker load center,
with bonded split neutral.
Design/Performance Features
• Two neutral bars, one bonded, one insulated,
connected with a cross strap and removable
bonding strap, allowing maximum versatility.
For service entrance applications, connect the
bonding strap and wire neutral and grounds to
both bars. For non-service entrance applications, disconnect the bonding strap and use
insulated bar for neutral and bonded bar for
grounds. No need to purchase accessory
ground bars.
LC2040L1125
LC330SS
Neutral bars provide two sizes of terminals
for maximum wire range usage.
• One-piece bus bar construction, through 200
amps, eliminates heat producing joints and
provides cooler operation with longer life.
Alstan® 88 plating with a copper strike
ensures maximum electrical conductivity and
corrosion prevention.
• Circuit breaker landing pads provide branch
circuit breakers positive fit and alignment.
• 100 through 225 amp load centers are offered
with combination surface/flush covers for
greater inventory flexibility substantially reducing inventory space and investment.
• NEMA 3R enclosures are constructed of G90
galvanized steel painted with an electrodeposition process providing uniform coverage for
maximum protection against corrosive environments and an attactive appearance.
• Bus protectors to guard against contamination
during installation and finish construction
work.
• Drywall gauge visibly embossed on four corners of enclosure to facilitate proper flush
mounting.
• Interior is made with a rugged steel basepan
to provide rigid support for plug-in circuit
breakers. One-piece steel construction with
400 Amp double main breaker load center,
includes a 200 Amp factory mounted main
breaker controlling a 30 circuit load center,
and provision for a second 200A breaker
for a remote load.
captive interior assembly hardware allows
easy removal of interior to facilitate quick wire
pulling.
• Keyhole and nail slots provide fast and easy
enclosure mounting.
• New knockout patterns are ideally sized and
located for maximum wiring flexibility.
125 Amp, 1ø, main lug load center with
insulated and bonded split neutral.
• Circuit directory is large and easy to read.
• Short circuit current rating is UL listed for
series ratings up to 100,000A IC using standard to 10,000A IC branch current.
• Murray's Rock Solid Warranty guarantees circuit breakers for a lifetime and load centers
for up to 10 years!
• Circuit identification labels preprinted for popular circuits, and peel and stick right next to
the circuit breakers.
Murray
Rock Solid Main Breaker Load Centers come with
2 bonded neutral bars.
& GFCI not included.
AFCI
2005 Electrical Distribution Products
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Load Centers
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Technical Information
Murray load centers have UL recognized short
circuit current ratings up to 100,000 Amps,
when used with appropriate main or feeder
(remote or internal) overcurrent devices. Load
center ratings are shown below. For load center applications with residential or commercial
metering equipment, refer to the appropriate
catalog section.
Load Center
Short Circuit
Load Center
Current Rating Main Rating
Internal or Remote
Main or Feeder
Circuit Breaker Type
10,000 Amps
22,000 Amps
Any
MP-HT, MQH MD-HTR, MQH ,
MPP-HT MQL MQL 42,000 Amps
65,000 Amps
100,000 Amps
Any
100/125 Amps
150/200/225
Amps
100/125 Amps
150/200/225
Amps
100/125 Amps
150/200/225
Amps
100/125 Amps
150/200/225
Amps
Remote
MP-MT, MPP-MT MPP-MT 100A, 300V AC, Class
‘T’ Fuse 200A, 300V AC, Class
‘T’ Fuse Series Ratings
Spaces Versus Poles
Series ratings allow two or three breakers to
be connected in series, such that the 2nd and
3rd breakers have an interrupting capacity less
than the system available fault current. Such
combinations must be tested, and only breakers of the type and ampere rating tested may
be used in this combination. Typical usage of
series ratings would be main and branch circuit breakers in load centers. The main breaker must have an interrupting capacity at least
equal to the available fault current. However,
the branch breaker may have an interrupting
capacity lower than the available fault current,
provided the pair have been tested together
as a series-rated pair.
The number of “spaces” available in a load
center is the maximum number of 1" single
pole circuit breakers that can be installed in
that load center. Because most load centers
will accept half-size breakers, the actual number of single pole breakers that may be
installed is often more than the number of 1"
spaces provided. In compliance with the
requirements of the National Electrical Code,
a physical means is provided to prevent the
installation of more circiut breakers than the
number of breakers for which the load center
was designed. This means of circuit limiting
allows the load centers to be UL Listed as
“Class CTL”.
Industry and Government
Specifications
Murray load centers meet or exceed the latest
edition of the following industry standards
and Government specifications, unless
noted otherwise:
Industry
NEMA—Standard #PB1
UL—Standards #50 and #67
Only
This
information is based on use of 10,000 AIC rated
branch circuit breakers in load center (MP-T, MH-T, MPGT, MG). Most series ratings exclude MH-T above 40
Amp. Consult device wiring diagram for specific data.
Circuit Breaker UL Type
Catalog No.
Prefix
MP(150-200A)
MP(15-125A)
MP(Duplex)
MP(Triplex)
MP(Quad Plex)
MP(GFCI)
MP(AFCI)
UL Type*
MD-TR OR MD-HTR
MP-T, MP-HT, MP-MT
MH-T
MH-T
MH-T
MP-GT, MP-HGT
MP-AT, MP-HAT
* UL Type is shown on circuit breaker label.
Types
MQH & MQL may be mounted internal in 150-225
amp 3ø main breaker load centers, and in 225 amp 1ø
main breaker load centers.
Lug Data
Wire Range
Amps
060
100
Phase
1ø
1ø
3ø
125 (4 CKT)
1ø
125 (6 CKT & Above) 1ø
3ø
150
1ø
3ø
All
Wire Range
Main Lug
Load Centers
Main Breaker
Load Centers
14-4
—
—
14-2/0
4-2/0
6-2/0
1/0-4/0
4-3/0
3-1/0
8-1/0
—
4-2/0
—
4-250 kcmil
2/0-300 kcmil
lugs are rated for Cu or A1 wire. Wire rang shown is
maximum allowable for bending space provided. Lug
may accommodate larger wire. Refer to National Electric
Code for specific wire size requirements.
Amps
Phase
200
500
1ø
3ø
225
1ø
3ø
400 (24 and 42 CKT) 1ø
400 (30 CKT Only)
1ø
400 (24 and 42 CKT) 3ø
Main Lug
Load Centers
Main Breaker
Load Centers
4-250 kcmil
4-250 kcmil
4-300 kcmil
4-300 kcmil
(1)3/0-500 kcmil
(2)3/0-250 kcmil
—
4-250 kcmil
4-250 kcmil
4-300 kcmil
4-300 kcmil
(1or2)3/0-250 kcmil
(1)3/0-500 kcmil
(2)3/0-250 kcmil
(1)3/0-500 kcmil
(2)3/0-250 kcmil
kcmil must be top side entry.
2005 Electrical Distribution Products
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LOAD CENTERS
Load Center Short Circuit
Current Rating