Bul. 140U
Installation Instructions for Bul. 140U N-Frame Circuit Breakers and Molded
Case Switches
DO NOT ATTEMPT TO INSTALL OR PERFORM MAINTENANCE ON EQUIPMENT WHILE IT IS ENERGIZED.
DEATH, SEVERE PERSONAL INJURY, OR SUBSTANTIAL PROPERTY DAMAGE CAN RESULT FROM
CONTACT WITH ENERGIZED EQUIPMENT. ALWAYS
VERIFY THAT NO VOLTAGE IS PRESENT BEFORE
PROCEEDING WITH THE TASK, AND ALWAYS FOLLOW GENERALLY ACCEPTED SAFETY PROCEDURES.
ALLEN-BRADLEY IS NOT LIABLE FOR THE MISAPPLICATION OR MISINSTALLATION OF ITS PRODUCTS.
The user is cautioned to observe all recommendations,
warnings and cautions relating to the safety of personnel
and equipment as well as general and local health and
safety laws, codes and procedures.
The recommendations and information contained herein
are based on Rockwell experience and judgement, but
should not be considered to be all-inclusive or covering
every application or circumstance which may arise. If any
questions arise, contact Rockwell for further information
or instructions.
1. INTRODUCTION
The N-Frame Circuit Breaker (Figure 1-1) are 690VAC
maximum rated devices, 600V for UL applications, and
have integral trip units. Available current ratings are up
to 1600 Amp, 1200 for UL applications. I N-Frame Circuit
Breakers and molded case switches are listed in accordance with Underwriters Laboratories, Inc. Standard
UL-489 and satisfy the requirements of the International
Electrotechnical Commission Recommendations No. IEC
60947-2.
The Trip Units are AC only devices that employ
microprocessor based technology that provides true
RMS current sensing means for proper correlation
with thermal characteristics of conductors and equipment.
The primary function of the Trip Unit is circuit protection.
This is achieved by analyzing the secondary current
40752-195 (1) Effective 2/2011
Figure 1-1 N-Frame Circuit Breaker
signal received from the circuit breaker current sensors and
initiating trip signals to the circuit breaker shunt trip when
pre-set current levels and time delay setting are exceeded.
Low level ground fault protection with an adjustable time
delay is supplied when appropriate trip types are selected.
In open air at 40º C, a N-Frame Circuit Breaker with a
Trip Unit will carry continuously up to 1200 amperes without
exceeding a 50º C rise at the terminals. The calibration
of the trip unit is insensitive to ambient temperatures over
a range of -20º to +55º C. However, the trip unit contains
thermal temperature protective circuitry that initiates a trip
operation for self-protection if the internal ambient temperature at the printed circuit board (PCB) reaches approximately 90º C. For ambient conditions above 40º C, derating of the circuit breaker should be considered to avoid
exceeding a safe terminal temperature operation range.
Consult Allen-Bradley for recommendations.
1
Molded Case Switches: The Molded Case Switch (MCS)
is similiar to the Circuit Breaker except that it has a differtrip at 15,000 Ampere but there is no overload short delay
or ground fault trip. As a result sections 2.6, 4.5, 6.8 and
7 are not applicable. In the remaining sections the term
circuit breaker shall also include the molded case switch.
Overload Trip: In accordance with standards requirements, the trip unit initiates a trip of the circuit breaker
within two hours of an overload of 135 percent, and a trip in
less time for higher overloads.
A “Thermal Memory” effect prevents the breaker from being
reenergized immediately after an overload. A “cooling off”
period of up to 5 minutes is required, which allows time for
the cabling to cool off.
Short delay/Instantaneous Trip: For short circuit conditions that exceed the short delay pick-up settings, the
trip units initiate a trip after a delay prescribed by the I²t
response time delay action is provided by trip unts designated LSI and LSIG unless the instantaneous (I) setting is
selected.
Table 1.1: Trip Unit Types
Trip Unit Functions
Long Time
Adjustable Ampere Rating
with Adjustable Long Delay
Short Time
Adjustable Short Time Pick-up
with Short Time Delay l²t Ramp
LS
Digitrip RMS 310+ Trip Unit
LSI
LSG
LSIG
•
•
•
Adjustable Short Time Delay
with Adjustable short Time Pick-up
Instantaneous
Fixed Instantaneous (Override)
•
•
•
•
•
MCS
•
•
•
•
•
Adjustable Ground Fault Pick-up
•
•
Adjustable Ground Fault Time
•③
•
Using Trip unit with adjustable delay (LSI, LSIG), instantaneous pick-up is achieved when the lowest
time delay setting (l) is selected for non-IMM trip units.
Override setting fixed at frame withstand rating.
③ I2t response.
Ground Fault
40752-195 (1) Effective 2/2011
2
Table 1.2: Trip Unit Function and Rating Sensing
Trip Function
Range/Setting Description ②
Ampere Rating Adjustable
with IR Switch
Trip Unit Ampere Rating (IR)
1250 Amp ③
1200 Amp
800 Amp
Short Delay Pick-Up (Adjustable) In Multiples of amperes (In) with marks at 2-3-4-5-6-7-8-9x
Short Delay Time (Adjustable)
I²t ramp configuration
Short Delay Time (Adjustable)
Flat response with time delay settings at Instantaneous, ① 120ms and 300ms.
Trip Unit Ampere Rating
Trip Unit Setting
Ground Fault
1200 Amp
Pick-Up
800 Amp
(Adjustable)
Ground Fault Time Delay
Flat Response with time settings of: Inst, 120ms and 300ms
Occurs
with
short
delay
time
adjustment
set at 1.
①
② The Molded Case Switch has a fixed instantaneous setting.
③ Not UL Listed
Ground Fault Protection: when selected, ground fault
pick-up and time delay settings shown in Table 1.2 allow
selective ground fault coordination with other circuit protection devices.
Internal Accessories: Internal accessories mount in the
breaker. A list of internal accessories and their instruction
DC Application: N-Frame trip units are suitable for AC application only.
Auxiliary Alarm
Alarm (Signal)/Lockout (ASL) Switch 40752-094
Auxiliary Switch
40752-097
Shunt Trip
40752-095
Low Energy Shunt Trip
Undervoltage Release Mechanism
(Handle Reset)
40752-096
Field Testing:
ing of the trip unit when connected to test kit.
Note: Shunt trip and undervoltage accessories, if required, must be mounted in the left pole.
Ground Fault Alarm: A ground fault alarm relay may be
ordered that provides a contact closure when a ground fault
trip occurs.
-
Note: Trip unit versions with ground
fault protection are supplied with an auxiliary switch,
mounted in the right pole of the trip unit.
3
40752-195 (1) Effective 2/2011
This instruction leaflet gives procedures for installation
and field testing of N-frame circuit breakers and describes
the different trip unit characteristics. For this publication,
the term circuit breaker shall also include the molded case
switch.
2. INSTALLATION
The installation procedure consists of inspecting the circuit
breaker, installing the accessories and terminals and, if
required, mounting the circuit breaker, connecting the line
and load conductors and accessory wiring, and adjusting
trip settings. Circuit breakers, accessories, and terminals.
may be supplied in separate packages. To install the circuit
breaker, perform the following steps:
2.1 Inspection
Make sure the circuit breaker is suitable for the intended
installation by comparing nameplate date with existing
equipment ratings and system requirements. Inspect the
circuit breaker for completeness and check for damage
before mounting.
2.2 Accessory Installation
Note: If required, internal accessory installation in
any type of circuit breaker should be done before the
circuit breaker is mounted and connected. Refer to the
individual accessory instruction leaflets listed above.
Figure 2-2 Conductor Extensions (Purchased Separately)
Terminals are not included.
Terminals must be purchased separately.
For bus connections use:
M12 - 1.75 bolts for Metric Style front mounted bus
connections, socket cap screws are recommended.
Torque Table (Domestic)
Terminal Cat.
Wire Size
No.
MCM
140U-N-TLA2 #1-500 (2)
140U-N-TLA3 3/0-400 (3)
140U-N-TLA4 4/0-500 (4)
140U-N-TLA3A 500-750 (3)
140U-N-TLC2 2/0-500 (2)
140U-N-TLC3 3/0-5-- (3)
140U-N-TL4
3/0-400 (4)
Cond.
Mat'l
CU/AL
CU/AL
CU/AL
CU/AL
CU ONLY
CU ONLY
CU ONLY
Torq.
Lb.-in.
375
375
375
450
300
300
275
Figure 2-1 Terminal Installation
40752-195 (1) Effective 2/2011
4
Torq.
Nm.vv
42.4
42.4
42.4
50.9
33.9
33.9
31.1
0.312-18
(M8-1.25) Tap
6-Places
3.438
(87.31)
1.718
(43.64)
CL Circuit
Breaker
CL Breaker
0.312-18
(M8-1.25) Tap
4-Places
CL Circuit
Breaker
Load End
8.625
(219.65)
14.750
(374.65)
CL Handle
1.906
(48.41)
2.50 R
(6.35 R)
CL Handle
.188 R
(4.76 R)
5.587
(141.91)
6.125
(155.57)
1.375
(34.92)
1.500
(38.10)
2.750
(69.85)
2.750
(69.85)
2.750
(69.85)
Dimensions
in Inches
(Millimeters)
4-POLE
2- AND 3-POLE
Figure 2-5 Breaker Mounting bolt Drilling Plan
3.187
(80.95)
6.375
(161.92)
FRONT COVER CUTOUT
Figure 2-6 Circuit Breaker Escutcheon Dimensions
2.3 Terminal Installation
1200A Front Connect
CAUTION
If not already installed, mount terminals.
The terminal cover screws must first be loosened
and the terminal covers removed.
CIRCUIT BREAKER COVER CONSTRAINTS MOVING
PARTS. DO NOT OPERATE THE BREAKER WITHOUT
THE COVER INSTALLED.
Figure 2-9 Securement of Cable (See caution note for bracing
instruction)
5
40752-195 (1)
CAUTION
VOLTAGE IN ENERGIZED EQUIPMENT CAN CAUSE
DEATH OR SEVERE PERSONAL INJURY. BEFORE
MOUNTING THE CIRCUIT BREAKER IN AN ELECTRICAL SYSTEM MAKE SURE THERE IS NO VOLTAGE
PRESENT WHERE WORK IS PERFORMED. SPECIAL
ATTENTION SHOULD BE PAID TO REVERSE FEED APPLICATIONS TO ENSURE NO VOLTAGE IS PRESENT.
2.4 Mounting
To mount the circuit breaker, perform the following steps:
1200A Front Connect Circuit
Breakers
OVERHEATING CAN CAUSE NUISANCE TRIPPING
AND DAMAGE TO THE CIRCUIT BREAKER. WHEN
ALUMINUM CONDUCTORS ARE USED, THE APPLICATION OF A SUITABLE JOINT COMPOUND IS RECOMMENDED TO REDUCE THE POSSIBILITY OF TERMINAL OVERHEATING.
Connect line and load conductors and accessory leads. If
the circuit breaker includes ground fault protection, connect
the neutral current sensor and ground fault alarm unit as
.
CAUTION
a. For individual surface mounting, drill mounting panel
using the drilling plan shown in Figure 2-5. For dead front
cover applications, cut out cover to correct escutcheon
dimensions, see Figure 2-6.
HAZARDOUS VOLTAGE CONDITIONS CAN CAUSE
DEATH OR SEVERE PERSONAL INJURY. MAINTAIN
ORIGINAL ELECTRICAL CLEARANCE AND CREEPAGE
SPACINGS AT TERMINATIONS
.
internal accessories, make sure the accessory wiring can
be reached when the circuit breaker is mounted.
After the circuit breaker is installed and all connections are
made, check all mounting hardware and terminal connection hardware for torque loading. Torque values for line/
load terminal lugs are given on table in Figure 2-1. Torque
mounting screws to 30-35 lb-ft. (41-47 Nm).
Note: Labels with accessory connection schematic
diagrams are provided on the side of the circuit breaker. A note should be made of the diagrams if the labels
cannot be seen when the circuit breaker is mounted.
c. Position the circuit breaker on the mounting surface.
d. Secure the circuit breaker with the supplied hardware
2.5 Connecting Line and Load Conductors
Re-install load end and line end covers and secure with
pan head screws provided. Torque large screws to 35-45
lb.-in. (4.0-5.0 Nm) and small screws to 24-30 lb-in. (2.7-3.4
Nm). When using the terminals TA700NB1 or T700NB1,
or when prospective fault currents of cabled installations
exceed 65kA, (such as NDC applications), the conductors
are to be braced in accordance with Figure 2-9.
CAUTION
UNSUPPORTED CABLES CAN CAUSE MINOR PERSONAL INJURY OR EQUIPMENT DAMAGE UNDER
SHORT CIRCUIT CONDITIONS.
Wrap conductor cables with 3/8” nylon or equivalent
rope as shown in Figure 2-9, having a minimum tensile
strength of 2000 lbs., at 6” from terminals and every additional 6” with 5 wraps or every additional 1” with 1 wrap.
2.6. Adjusting Trip Settings
The N-frame circuit breakers have the trip unit built in as
an integral part of the breaker. The trip unit is not field
replaceable. The various trip unit settings are described
in section 4. They should be adjusted as required
at this point.
40752-195 (1)
2/2011
6
4X Ø.344 MTG HOLES
Ø.703 CBORE X .453 DP
.359 DP FROM BOTTOM
11.500
OF TERMIALS
7.000
8.625
14.750
OF MTG HOLES
16.000
OVER ALL LENGTH
9.250
REMOVABLE
TERMINAL
COVER
2.799
3.819
HANDLE
2.490
1.375
2.750
REMOVABLE
TERMINAL
COVER
4.125
8.250
Figure 3-1 Circuit Breaker Manual Controls
3.2 Circuit Breaker Reset
3. OPERATION
3.1 Manual Operation
Manual operation of the circuit breaker is controlled by the
circuit breaker handle and the Push-to-Trip button. The
circuit breaker handle has three positions, two of which
are shown on the cover raised lettering to indicate ON and
OFF. On the handle, ON, OFF, and TRIP are also shown
by a color-coded strip for each circuit breaker handle position: red for ON, white for TRIP, and green for OFF (See
Figure 3-1). The Push-to-Trip button checks the circuit
breaker tripping function and may be used to periodically
exercise the operating mechanism.
7
After an automatic or accessory initiated trip, or a manual
Push-to-Trip operation, the circuit breaker is reset by moving the circuit breaker handle to the extreme OFF position.
CAUTION
LACK OF ILLUMINATION OF THE STATUS LIGHT DOES
NOT INDICATE THE TERMINALS OF THE BREAKER
ARE DEENERGIZED.
40752-195 (1) Effective 2/2011
4-1 . Test Port - a test port is built into each
trip unit to allow use of a functional test kit.
The test kit performs a test of the Long Delay,
Short Delay, and Ground Fault functions.
4. TRIP UNIT ADJUSTMENTS
6646 C06 H01
STATUS
G 7
H 4
3
6646 C06 H01
Push to Trip
IR
D E F
A
3
tR (s)
LONG
10 12 15
G 7
H 4
5
6
A
3
6646 C06 H01
IR
D E F
A
3
tR (s)
LONG
10 12 15
G 7
H 4
2
I sd (xIR )
SHORT
5 6 7
8
20 4
24 3
9
2
9
5
4
tsd (ms)
SHORT
120
Inst.
300
A
B
C
D
E
F
G
H
I
J
7
6646 C06 H01
STATUS
TEST / ALARM
C
B
3
IR
D E F
A
tR (s)
I sd (xIR )
LONG
SHORT
5 6 7
10 12 15
G 7
8
20 4
H 4
9
24 3
2
9
2
4
40752-195 (1) Effective 2/2011
B
C
D
E
F
G
H
I
J
A
4-3 . IR - Continuous Current Setting. In
accordance with standards requirements, the
trip unit initiates a trip of the circuit breaker
within 2 hours for an overload of 135% and
will trip as a function of 12 t for higher currents. Continuous Current Values for each
lettered setting are indicated by the chart on
the right side of the trip unit.
4-5 . Isd - Setting in multiples of IR. For
short circuit conditions that exceed the short
delay pick-up setting, the trip unit initiates a
trip after a predetermined delay.
4-6 . The - Ig (xIn) switch is the ground fault
pick-up switch and is used on the LSIG &
LSG styles to set the ground fault pick-up as a
percentage of I (Frame current). For example,
a 1200A frame with an Ig (xIn) setting of 0.4
will provide a ground fault pick-up at 480A.
3
10
2
4-2 . Test LED - to be used with a no trip
functional test. This LED is a dual function
light. As previously stated, the LED is used
as a no trip indicator when using the test port.
In normal modes, this LED indicates a high
load alarm. It will light if the continuous current is 95% of the setting and must be present
for a 38 second duration.
4-4 . tR - The number of seconds required to
trip @ 6x. For example, IR - 800A, - 2 sec
load current - 4800A (6x). The breaker will
trip in 2 seconds.
NOTE: The last two time settings vary
according to the frame as follows: 1200A 20,24, 1250A\800A - 14,14, 1600A - 20,20.
NOTE: There is a thermal memory capacitor
that will affect the LDT time. If the breaker
has tripped on LD, this capacitor must be
discharged or it will self discharge after five
minutes. If neither one of these choices has
been done, the LD trip time will be shorter.
9
STATUS
C
B
11
2
B
C
D
E
F
G
H
I
J
10
TEST / ALARM
Push to Trip
I sd (xIR ) I g (xIn)
tg (ms)
SHORT GND
GND
120
5 6 7
.6 .8 1.0
8 .4
20 4
9 .3
Inst.
300
24 3
2
.2
9
4
2
1
tg (ms)
Inst. 120 300
K
J
L
M N
O
P Q R
3
TEST / ALARM
11
tsd Inst.
120
(ms)
300
8
STATUS
11
Push to Trip
6
Settings
10
C
B
1
5
4
2
1
2
*
6646 C05 H04
11
A
I sd (xIR ) I g (xIn) tsd / tg (ms)
SHORT / GND
SHORT GND
5 6 7
.6 .8 1.0
M N O
20 4
8 .4
L
P
24 3
K
Q
9 .3
2
.2
J
9
R
6646 C05 H07
C
B
IR
D E F
*
tR (s)
LONG
10 12 15
TEST / ALARM
A
B
C
D
E
F
G
H
6646 C05 H10
Push to Trip
3
8A
6646 C05 H01
10
2
1
4-7 . For the LSI style, the Short Delay time is
a flat response determined by the tsd/tg switch
setting of INST, 120ms or 300ms. For the LS
style, the short delay time is an 12t function.
5
8
H04
A
Ii(xIn)
INST
7 8 10
6
12
4
2.5
Maintenance Mode
*
TEST / ALARM tR (s)
IR
D E F
C
B
A
Isd (xIR) Ig (xIn) tsd /tg (ms)
Settings tg (ms)
LONG
SHORT GND
SHORT / GND
120 300
Inst.
10 12 15
5 6 7
.6 .8 1.0 M N O
J K
L
20 4
G 7
8 .4
L
P
tsd 50ms
M N
O
120
24 3
H 4
K
Q
9 .3
(ms)
P Q
R
300
2
2
.2
J
9
R
*
12
6646
B
C
D
E
F
G
H
I
J
STATUS
6646
Push to Trip
C06
Remote MM
C05
H01
13
response determined by the tsd/tg switch settings of INST, 120ms or 300ms. This switch is
a dual switch that also determines
the ground fault time settings of INST, 120ms
or 300ms. As an example, if the tds/tg switch
is set at a position J, then both short delay time
ond example would be to set the tsd/tg switch
The LSIG label (see balloon 8A) should be
used in conjuction with the tsd/tg switch to set
any one of nine possible combinations of short
14
label should be applied to the right side breaker
trip unit nameplate.
4P 4d
STATUS
TEST / ALARM tR (s)
IR
D E F
4P 3dn/2
4P 3d
C
B
LONG
10 12 15
G
H
A
20 4
24 3
7
4
2
*
Isd (xIR) Ig (xIn) tsd /tg (ms)
Settings tg (ms)
SHORT GND
SHORT / GND
120 300
Inst.
5 6 7
.6 .8 1.0 M N O
J K
L
8 .4
L
P
tsd Inst.
M N
O
120
K
Q
9 .3
(ms)
P Q
R
300
2
.2
J
9
R
*
14
B
C
D
E
F
G
H
C05
A
is set by the tg switch. For the LS style, the
short time is an I2t function.
6646
6646
Push to Trip
C06
H02
H01
4-9 . For the LSG style, the short delay time is
4-10 . Status LED - A green status light indicates the operational status of the trip unit. If
the load current is approximately 20% of the
maximum current rating (In) of the breaker,
the status light will blink on and off once each
second.
4-11 . Mechanical Push to Trip.
4-12 . The Maintenance Mode and adjustable
INSTantaneous features are only available on
LSI and LSIG styles. Please refer to the labeling to the left of the test kit connector. The
Maintenance Mode consists of the two lowest
settings of the INST switch: 2.5x and 4.0x.
For example, a 1200A (In) NG breaker with the
switch set to 2.5x would trip instantaneously
when the current exceeded 3000A.
4-13 . The adjustable INSTantaneous (Ii) Mode
has four settings from 6x to 9x. For example, a
800A (In) NG breaker with the (Ii) switch set to
7x would trip instantaneously with the current
at or above 5600A. The last setting on the (Ii)
switch can be one of three values depending
on the frame current: 800A=28, 1200A=12,
1600A=9.
4-14 . On a breaker without Maintenance Mode,
the lowest labeled SDT setting is labeled INSTaneous. The lowest SDT setting with Maintenance Mode is labeled as 50ms.
9
40752-195 (1) Effective 2/2011
4-15 . The Remote Maintenance Mode is enabled by applying 24VDC to the two wire cable that exists the left side of the
breaker. The wires are color coded as follows: Yellow=+24V
and Black=common ground. A blue colored LED on the left side
of the breaker is the Maintenance Mode section
of the trip unit. The lighted blue LED indicates that the
lowest setting of the Maintenance Mode is enabled. This setting
corresponds to 2.5x of In. Turning the adjustable switch on the
trip unit has no affect on either the Maintenance Mode or the
INST Mode settings while the blue LED is lit. In addition to the
blue colored LED, a relay contact (C, NO) is available. The wires
for this contact exit the left hand side of the breaker and are color
coded as follows: Blue=C, and Red=NO.
NO
NC
-
4-16 . The High Load Alarm Relay option will provide a SPST
contact closure when the trip unit current equals or is greater than
95% of In for a period of 38 seconds. If the current drops below
the 95% value, the contact will open. The yellow and green wires
that exit the right side of the breaker are the common (C) and nor
mally (NO) of this relay.
+
4-17 . The Ground Fault Relay option will provide a SPST contact closure immediately before the breaker will trip on a ground
fault over current detect. This closure is momentary (50ms) and
the customer must provide the necessary external circuitry in order to latch this signal. The yellow and green wires that exit the
right side of the breaker are the common (C) and normally (NO)
of this relay.
NOTE: Either the high Load Alarm Relay or the Ground Fault
Alarm Relay option can be selected but not both. The High
Load Alarm Relay can only be selected with LS and LSI trip unit
styles. If the trip unit is a Ground Fault style, the Alarm A Relay,
by default, will be selected.
NOTE: The contact rating of the relay is: 2A, 30 VDC
resistive load. The coil resistance is approximately
1600 ohms. (Max switching voltage: 220 VDC, Max switching
current: 2A). The coil resistance is about 1600 ohms.
40752-195 (1) Effective 2/2011
LEFT SIDE OF BREAKER
BLACK
YELLOW
-
+
24 VOLT DC
BLUE
RED
10
Polarity
Markings
.59
(14.98)
2.75
(69.85)
1.062
(26.97)
M12-1.75 Tapped Holes
4-Places
4.375
(111.13)
2.188
(55.58)
3.12
(79.25)
1.69
(42.93)
.50
(12.7)
5.80
(147.32)
2.75
(69.85)
Figure 5-1 Neutral Sensor Outline
White
Grey
Figure 5-2 Connection Diagrams Ground Fault Breaker - Figure indicates normal feed installation. Neutral sensor is wired identically for reverse feed applications.
11
40752-195 (1) Effective 2/2011
5. Ground Fault
Ground fault circuit breakers detect ground fault currents
through residual sensing (they are not designed to use
source ground or zero sequence ground fault sensing
methods). If the system neutral is grounded, but no phase
to neutral loads are used, the neutral current sensor is not
necessary.
If the system neutral is grounded and phase or neutral
loads are used, then the neutral current sensor (see Figure
5-1) must be used. It should be connected to the breaker
according to Figure 5-2.
The neutral sensor has the same ratio as the breaker current sensors.
Note: The polarity of the sensor connections is critical.
Always observe the polarity markings on the installation drawings. To insure correct ground fault equipNational Electric Code requirements under article 23095(C). See section 7 for testing instructions.
6. INSPECTION AND FIELD TESTING
Inspection
Circuit breaker should be inspected periodically. This
inspection can be best done during normal equipment
maintenance periods when no voltage to the equipment
is available. The inspection should include the following
checks 6-1 through 6-8.
6.1 Remove dust, dirt, soil, grease, or moisture from the
surface of the circuit breaker using a lint-free dry cloth,
brush, or vacuum cleaner. Do not blow debris into the circuit breaker. If contamination is found, look for the source
and eliminate the problem.
6.2 Switch circuit breaker to ON and OFF several times to
be sure that the mechanical linkages are free and do not
bind. If mechanical linkages are not free, replace circuit
breaker.
6.3 With the circuit breaker in the ON position, press the
PUSH-TO-TRIP button to mechanically trip the circuit
breaker. Trip, reset, and switch circuit breaker ON several
times. If mechanism does not reset each time the circuit
breaker is tripped, replace the circuit breaker.
6.4 Check base, cover, and operation handle for cracks,
chipping, and discoloration. Circuit breakers should be
replaced if cracks or severe discoloration is found.
6.5 Check terminals and connectors for looseness or signs
of overheating. Overheating will show as discoloration,
melting, or blistering of conductor insulation, or as pitting
or melting of conductor surface due to arcing. If there is
no evidence of overheating or looseness, do not disturb or
tighten the connections. If there is evidence of overheating, terminatons should be cleaned or replaced. Before
re-energizing the circuit breaker, all terminations and cable
should be refurbished to the same condition as when originally installed.
6.6 Check circuit breaker mounting hardware, and tighten
if necessary.
6.7 Check area where circuit breaker is installed for any
VOLTAGES IN ENERGIZED EQUIPMENT CAN CAUSE
SEVERE PERSONAL INJURY OR DEATH BEFORE
INSPECTING THE CIRCUIT BREAKER IN AN ELECTRICAL SYSTEM. MAKE SURE THE CIRCUIT BREAKER IS
SWITCHED TO THE OFF POSITION AND THAT THERE
IS NO VOLTAGE PRESENT WHERE WORK IS TO BE
PERFORMED. SPECIAL ATTENTION SHOULD BE PAID
TO REVERSE FEED APPLICATIONS TO ENSURE NO
VOLTAGE IS PRESENT.
Exposure to certain types of chemicals can cause deterioration of electrical connections.
7. PERFORMANCE TESTING FOR GROUND FAULT
CIRCUIT BREAKERS
7.1 Code Requirements
The National Electric Code under Article 230-95-C
requires that any ground-fault protection system be
SOME COMMERCIAL CLEANING AGENTS WILL DAMAGE THE NAMEPLATES OR MOLDED PARTS. MAKE
SURE THAT CLEANING AGENTS OR SOLVENTS USED
TO CLEAN THE CIRCUIT BREAKER ARE SUITABLE
FOR THE JOB.
40752-195 (1) Effective 2/2011
12
The test shall be conducted in accordance with approved instructions provided with the equipment. A
written record of this test shall be made and shall be
available to the authority having inspection jurisdiction.
Figure 7-1a. This should cause the breaker to trip in less
than 1 second, and if an alarm indicatior is supplied, it
should operate. Reset the breaker and the alarm indicator.
Repeat the test on the other two phases.
7.3.5 If the system is a 4-wire system with a neutral current
sensor, apply the same current as described in paragraph
7.3.4 above through one phase of the breaker, returning
As a follow-up to the basic performance requirements
stipulated by the N.E.C. as stated above in 7.1, UL Standard through the neutral sensor, as shown in Figure 7-1b. The
breaker should not trip and the alarm indicator, if supNo. 1053 requires that certain minimum instructions must
plied, should not operate. Repeat the test on the other two
accompany each ground fault protection system. These
phases.
following statements plus a copy of the test record form
are shipped with each N-Frame ground fault circuit
breaker.
7.3.6 If the system is a 3-wire system with no neutral current sensor, apply the same current as described in para7.3 General Test Instructions
graph 7.3.4 above through any two phases of the breaker,
with the connections exactly shown in Figure 7-1c. the
7.3.1 The interconnected system shall be evaluated in acbreaker should not trip, and the alarm indicator, if supplied,
cordance with the equipment assembler’s detail instruction
should not operate.
7.2 UL Standards Requirements
7.3.2 The polarity of the neutral sensor connection (if used)
must agree with equipment assembler’s detailed instructions to avoid improper operations following apparently
correct simulated test operations. Where a question exists,
consult the specifying engineer and/or equipment assembler.
Repeat the test using the other two combinations of breaker phases.
7.3.3 The grounding points of the system shall be veri-
FIELD TESTING SHOULD BE USED FOR FUNCTIONAL
TESTING AND NOT FIELD CALIBRATION.
bypass the sensors. High-Voltage testers and resistance
bridges may be used.
THERE IS A HAZARD OF ELECTRICAL SHOCK OR
BURN WHENEVER WORKING IN OR AROUND ELECTRICAL EQUIPMENT. ALWAYS TURN OFF POWER
SUPPLYING BREAKER BEFORE CONDUCTING TESTS.
CAUTION
ANY TEMPORARY CONNECTION MADE FOR THE
PURPOSE OF CONDUCTING TESTS SHOULD BE
RESTORED TO PROPER OPERATING CONDITIONS
BEFORE RETURNING THE BREAKER TO SERVICE.
7.3.7 The results of the test are to be recorded on the test
form provided with the equipment.
Note: Since the ground fault circuit breakers derive
their operating power from the phase current, and not
from the neutral current, passing current through the
neutral sensor only will not properly test the ground
fault feature.
7.3.4 Using a low voltage (0-24V), high current, AC source,
apply a test current of 125% of the ground fault pick-up setting through one phase of the circuit breaker, as shown in
13
40752-195 (1) Effective 2/2011
Low
Voltage
Source
Source
L
Low
Voltage
Source
Source
C
Load
R
N
Current Limiting
Resistor
(if required)
Figure 7-1a Connections for Ground
Fault Trip Test
40752-195 (1) Effective 2/2011
L
Low
Voltage
Source
Source
C
Load
R
N
L
C
R
Current Limiting
Resistor
(if required)
Current Limiting
Resistor
(if required)
Figure 7-1b Connections for Ground
Fault No-Trip Test with a Four Wire
System
Figure 7-1c Connections for
Ground Fault No-Trip Test with a
Three Wire System
14
NOTES
15
40752-195 (1) Effective 2/2011
DISCLAIMER OF WARRANTIES AND LIMITATION OF
LIABILITY
The information recommendations, descriptions and safety
notations in this document are based on Rockwell Automation's
experience and judgement and may not cover all contingencies.
should be consulted.
THERE ARE NO UNDERSTANDINGS, AGREEMENTS,
WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING
WARRANTIES OF FITNESS FOR A PARTICULAR PURPOSE OR MECHANTABILITY, OTHER THAN THOSE
SPECIFICALLY SET OUT IN ANY EXISTING CONTRACT
BETWEEN PARTIES. ANY SUCH CONTRACT
STATES THE ENTIRE OBLIGATION OF ROCKWELL.
THE CONTENTS OF THIS DOCUMENT SHALL NOT
BECOME PART OF OR MODIFY ANY CONTRACT BETWEEN THE PARTIES.
PRINTED IN USA
40752-195 (1) Effective 2/2011
16
">
