I.L. 29C103G
JWC Circuit Breakers and Molded Case Switches
nel and equipment as well as all general and local
health and safety laws, codes, and procedures.
The recommendations and information contained herein
are based on Cutler-Hammer experience and judgment,
but should not be considered to be all-inclusive or covering every application or circumstance which may
arise. If any questions arise, contact Cutler-Hammer for
further information or instructions.
1. INTRODUCTION
General Information
The J-frame Series C circuit breaker (Figure 1-1) types
JD, JDB, HJD, and JDC are 600 Vac maximum rated
devices with inter changeable thermal-magnetic trip
units rated 250A maximum continuous current. Circuit
breaker types JW, HJW, and JWC are 660 Vac maximum rated devices using interchangeable adjustable
thermal/adjustable magnetic or electronic trip units rated
up to 250A continuous current. The type JDB noninterchangeable trip circuit breaker is rated 600 Vac maximum with a maximum continuous current rating of
250A. Refer to Table 1-1 for all available trip unit rat-
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.
CUTLER-HAMMER 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 person-
Figure 1-1 J-Frame Model D Series C Circuit Breaker
with JT Trip Unit Installed
WARNING
Circuit Breaker Trip Unit Types
Types Thermal-Magnetic Amperes I
n
Fixed Adjustable Adjustable
Thermal Thermal Magnetic
of I
n
JDB 70 5 to 10
JD 90
HJD 100
JDC JW 125 100-125
HJW 150 125-160
JWC
175
200 160-200
225
250 200-250
Not UL listed.
For adjustable thermal trip units, the magnetic setting is a multiple
of the maximum thermal setting.
Table 1-1 Available Trip Unit Ratings
Installation Instructions for JDB, JD, HJD, JDC, JW HJW,
!
1
2
1
2
I.L. 29C103G
Page 2
Effective 1/10
ings. Model D circuit breakers are listed in accordance
with Underwriters’ Laboratories, Inc. Standard UL489
and satisfy the (P1) requirements of the International
Electrotechnical Commission Recommendations No.
IEC 157-1 Model W circuit breakers satisfy the requirements of IEC 947-2. Molded case switches are listed in
accordance with UL 489.
This instruction leaflet (IL) gives procedures for installation and field testing of J-frame Series C circuit breakers. 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 and, as applicable, installing the trip unit,
accessories, interphase barriers and terminals; mounting the circuit breaker; connecting the line and load conductors; torquing terminals; and attaching terminal
shields. Circuit breaker frames, trip units, accessories,
mounting hardware, and unmounted terminals may be
supplied in separate packages. To install the circuit
breaker, perform the following steps.
JDB circuit breakers are factory sealed for reverse
feed applications under UL489. UL requires that
internal accessories be installed at the factory in
this type of circuit breaker.
For hardware conversion kits and handle mechanisms
required to replace existing Cutler-Hammer circuit
breakers.
If required, internal accessory installation in any type of
circuit breaker should be done before the circuit breaker
is mounted and connected. Refer to individual accessory instruction leaflets.
Circuit breaker mounting hardware is supplied separately.
2-1. Make sure that the circuit breaker frame is suitable
for the intended installation by comparing nameplate
data with existing ratings and system requirements.
Inspect the circuit breaker for completeness, and check
for damage before mounting. Uninstalled cover mounting hardware is supplied in a plastic bag with the circuit
breaker frame. (See Figure 2-1)
2-2. Remove installed cover screws and cover.
Figure 2-1 Cover Mounting Hardware
Pan Head Screws
Thread-Forming Screws
Figure 2-2 Cover Screw Installation Positions
On/
Off/
Screw, .190-32 x 3.13 Inch, Pan Head, Cross-Recessed.
Screw, No. 8 x 1.88 Inch, Pan Head, Cross-Recessed,
Thread Forming.
Screw, No. 6 x 1.50 Inch, Pan Head, Cross-Recessed,
Thread Forming (used with 4 Pole Only)
Note: Hatched lines show additional pole and screws for
4-pole circuit breaker.
I.L. 29C103G
Effective 1/10
The circuit breaker handle must be in the tripped or
OFF position to remove the cover. Instructions for
installing the trip unit accessories are supplied with
the devices.
2-3. If not already installed, mount trip unit and accessories (if required) in circuit breaker frame.
WHEN REMOVED AND REINSTALLED, THREADFORMING SCREWS WILL TRY TO REFORM THE
THREADS IN THE BASE. CARE SHOULD BE TAKEN
EVERY TIME A THREAD-FORMING SCREW IS USED
TO ENSURE THE SCREW STARTS IN THE ORIGINAL
THREADS. DAMAGED THREADS CAN RESULT IN
IMPROPER CIRCUIT BREAKER COVER RETENTION.
2-4. Install cover, and secure with pan-head screws followed by threadforming screws, as shown in Figure 2-2.
2-5. If not already installed, mount terminals as shown
in Figure 2-3. When using terminal (Catalog No.
TA250KB), secure the terminal to the circuit breaker
using a 1/8-inch socket wrench and torque to 6-8 lb.-ft
(8-11 N.m). After mounting the circuit breaker and
before installation of the conductors, the terminal mounting screw can be checked or retightened through the
terminal when the conductor screw is removed. When
using terminal (Catalog No. T250KB), secure the terminal to the circuit breaker using screw and nut. Torque to
7-9 lb.-in (0.8-1.0 N.m).
THE VOLTAGES 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 TO BE PERFORMED. SPECIAL ATTENTION SHOULD BE PAID
TO REVERSE FEED APPLICATIONS TO ENSURE
NO VOLTAGE IS PRESENT.
Depending on the equipment configuration, the circuit breaker can be mounted using different styles
of hardware. The following steps describe how to
mount the circuit breaker using standard hardware.
When special hardware is needed (for example, with
the electrical operator), the instruction leaflet
describing the accessory also describes the special
mounting arrangements.
2-6. To mount the circuit breaker, perform the following
steps:
a. For individual surface mounting, drill mounting panel
using the drilling plan shown in Figure 2-4. For panelboard mounting, only load end support mounting
holes are required. For deadfront cover applications,
cut out cover to correct escutcheon dimensions. (See
Figure 2-5)
b. If circuit breaker includes factory- or field-installed
internal accessories, make sure that accessory
wiring can be reached when the circuit breaker is
mounted.
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.
Figure 2-3 Terminal Installation
Terminal
Connectors
TA250KB Terminal
Collar
Page 3
Collar
Socket
Screw
Flat-Head
Screw
T250KB Terminal
Nut
Torque cover screws to 18-23 lb-in (2-2.6 N.m.).