Breaker-based transfer switches
Proven design
experience
and reliability
Automatic
Manual
Non-Automatic
30–1000A
2
EATON CORPORATION Breaker-based transfer switches 
Built with years of experience
Powered with innovation
Delivered with reliability
A history of experience,
innovation and reliability
As a premier industrial
manufacturer, Eaton’s electrical
business is one of the world’s
leading suppliers of electrical
control products and power
distribution equipment, with
yearly sales of over $2.5 billion.
Eaton’s electrical products
include a complete line of
low and medium voltage
assemblies, from substations,
switchgear and panelboards,
to loadcenters, transformers
and safety switches. These
products are used wherever
there is a demand for electrical
power in residences, high-rise
apartment and office buildings,
commercial sites, hospitals
and factories.
Built with experience
Powered with innovation
Delivered with reliability
For over a century, Eaton has
focused on providing quality
power-centric products and
services. In today’s business
environment, customers like you
are driving our transformation
from a leading global electrical
components provider into a
customer-centric solutions
partner who understands your
business. We do this through
in-depth collaboration with
customers and subject-matter
experts studying the issues
inherent in the electrical power
distribution and control systems.
Eaton continues to meet
changing industry needs by
providing a broad range of
automatic transfer switches.
These switches may be grouped
into a basic, enhanced or
premium set of features that
will meet your application
requirements. Eaton has used
industry-leading breaker-based
designs for years and now has
a line of contactor-based designs.
Power outages due to bad
weather or utility failure have
grown increasingly costly and
more disruptive to businesses
and homeowners. A backup
power system will keep your
computers, security system,
heating or refrigeration system,
cash registers, home health care
equipment, or any system that
uses electric power energized
and operational. The demands
for reliability have increased.
Eaton meets those expectations
by the stringent ULT 1008
automatic transfer switches
with a world-class product
delivery system.
Eaton is one of the pioneering
electrical manufacturers and
has been focused on providing
reliable backup power systems
with transfer switch equipment
for over 75 years.
These designs can be matched
to a family of automatic transfer
switch controllers that will meet
your specific needs. Identify
your application, define your
needs and select the solution
from Eaton.
Eaton will provide the individual
transfer switch built to exacting
standards or supply the same
transfer switch in an integrated
lineup with other Eaton gear.
For startup service, application
support and emergency support,
call Eaton Electrical Services &
Systems at 1-800-498-2678.
EATON CORPORATION Breaker-based transfer switches 
3
4
EATON CORPORATION Breaker-based transfer switches 
Breaker-based transfer switches
Switch type—overview and standards
Solutions overview
Enhanced solution
Eaton’s automatic transfer
switches are designed to
provide you with a full offering
of transfer switches to handle
your industry and application
needs. Eaton offers the
industry’s most complete line
of contactor-based, breakerbased and MagnumE-based
transfer switches.
The enhanced solution meets all
of the basic automatic transfer
switch needs. In addition to
meeting the most basic transfer
switch requirement, the
enhanced solution allows for
optimal control and improved
flexibility. This solution set
allows you to choose from
either a contactor-based or
a breaker-based design.
This wide range of selections
enables you to identify your
application needs and the
benefits you expect to realize,
and then choose the solution
best for you. The cornerstone
of these offerings is the
proven design experience
and reliability built into all
Eaton transfer switches.
Basic solution
The basic solution offers a
transfer switch that meets the
most basic and cost-effective
requirements for an automatic,
manual or non-automatic
transfer switch.
This solution set allows you to
choose from either a contactorbased or a breaker-based design
and match that power-switching
device with our basic transfer switch controller.
Premium solution
The premium solution is offered
for those applications requiring
continuity of power during
the transfer and routine test.
This solution set offers both
contactor-based and breakerbased designs with drawout
capability.
Switch types available
•
Open transition
•
Closed transition
•
Delayed transition
•
Bypass isolation
Transfer Switch Standards
UL 991
UL 1008
NEMAT ICS 109.21
IEEET 472 (ANSI C37.90A)
EN55022
EN61000-4-2 Class B
EN61000-4-3
EN61000-4-4
EN61000-4-5
EN61000-4-6
EN61000-4-11
FCC Part 15
CISPR 11
IEC 1000-2
IEC 1000-3
IEC 1000-4
IEC 1000-5
CSAT conformance
UL 869A
UL 50/508
NEMA ICS 1
NEMA ICS 2
NEMA ICS 6
NEMA ICS 10-1993
ANSI C33.76
UL standards for safety tests for safety-related
controls employing solid-state devices
Dielectric test
Impulse withstand test
Ringing wave immunity/voltage surge test
(CISPR11): Conducted and radiated emissions
Level 4 ESD immunity test
(ENV50140) Radiated RF,
electromagnetic field immunity test
Electrical fast transient/burst immunity test
IEEE C62.41: Surge immunity test
(ENV50141) Conducted immunity test
Voltage dips and interruption immunity
Conducted/radiated emissions (Class A)
Conducted/radiated emissions (Class A)
Electrostatic discharge test
Radiated susceptibility tests
Fast transient tests
Surge withstand tests
C22.2 No. 178-1978 (reaffirmed 1992)
Reference standard for service equipment
Enclosures
General standards for industrial control systems
Standards for industrial control devices,
controllers and assemblies
Enclosures for industrial controls and systems
AC automatic transfer switches
Enclosures
NECT 517, 700, 701 and 702 National Electrical CodeT
National Electrical Code
NFPAT 70
NFPA 99
NFPA 101
Health care facilities
NFPA 110
EGSA 100S
CSA C22.2 No. 178-1978
Life Safety CodeT
Emergency and standby power systems
Standard for transfer switches
Canadian Standards Association
EATON CORPORATION Breaker-based transfer switches 
5
Make the right decision:
• Identify your application
• Define your needs
• Determine your right solution
• Select Eaton
ATS Solution Guide: Highlighting Contactor-Based Designs A
Eaton Solution
Customer Benefits
Key Features
Agriculture
Premium solution
Greater reliability to avoid lost revenue and production time
Continuity of power through synchronization of sources
Lower energy costs realized through managing demand charges
No power interruption during switch inspection or testing
Soft load ramping
30 cycle, 85 kA short-time ratings
Integral overcurrent protection available
Drawout design
—
Greater reliability to avoid lost revenue and production time
Safe preventative maintenance without power interruption
No power interruption during switch inspection or testing
30 cycle, 85 kA short-time ratings
Integral overcurrent protection available
Integrated service entrance solution
Interchangeable bypass and switch devices
Drawout design
Interchangeable bypass and switch devices
Drawout design standard
Front access standard
Dual ATS
—
Continuity of power
during retransfer
Critical load transfer
applications
Maximum control
and ultimate flexibility
Maximum investment
Greater reliability to avoid lost revenue and production time
Safe preventive maintenance without power interruption
No power interruption during switch inspection or testing
Greater reliability to avoid lost revenue and production time
Lower energy costs realized from managing demand charges
No power interruption during generator set testing
30 cycle, 85 kA short-time ratings
Integral overcurrent protection available
Integrated service entrance solution
Drawout design available
Greater reliability to avoid lost revenue and production time
Paralleled in less than 100 ms
Lower energy costs realized from managing demand charges
Programmable field settings
No power interruption during generator set testing
Communication capability
Enhanced solution
Ability to transfer large motor or inductive loads
30 cycle, 85 kA short-time ratings on power circuit breaker
Allows loads to re-energize after transfer at normal inrush currents Integral overcurrent protection available
Momentary loss
Avoid higher starting currents, which increase energy costs
Integrated service entrance solution
of power acceptable
Ability to transfer large motor or inductive loads
Multi-tap transformer voltage selection available
during retransfer
Allows loads to re-energize after transfer at normal inrush currents
Easily adjustable time delays for the neutral position
Avoid higher starting currents, which increase energy costs
Optimal control
Ability to transfer large motor or inductive loads
30 cycle, 85 kA short-time ratings on power circuit breaker
and improved flexibility
Allows loads to re-energize after transfer at normal inrush currents
Integral overcurrent protection available
Avoid higher starting currents, which increase energy costs
Integrated service entrance solution
Moderate investment
Drawout design available
Simplest of transfer switching solution
Equal withstand, interrupting and closing ratings
Safe manual transfer under load
Integral overcurrent protection available
Integrated service entrance solution
Basic solution
Most simple operation
Most compact offering
Most cost-effective
Multi-tap transformer voltage selection available
Momentary loss
Application flexibility
of power acceptable
Permits safe and convenient non-auto transfer under load
30 cycle, 85 kA short-time ratings on power circuit breaker
during retransfer
Integral overcurrent protection available
Drawout design available
Least critical load
Permits safe and convenient manual transfer under load
Equal withstand, interrupting and closing ratings
transfer applications
Most cost-effective manual transfer
Integral overcurrent protection available
Deadfront design
Basic control and flexibility
Minimum investment
Special solution
Continuity of power for UPS applications
A Emphasis in yellow bars.
6
EATON CORPORATION Breaker-based transfer switches 
Required UPS bypass signal prevents unauthorized bypass
High interrupting ratings
Reliable, manually initiated electrical operation
—
—
—
—
—
—
Open transition
Breaker-based
(100–1000A)
Open transition
Contactor-based
(100–600A)
—
—
—
Commercial
Industrial
Utilities
Institutions
Government
Communications
Data Center
—
—
Soft load
Magnum-based
(600–5000A)
Soft load
Magnum-based
(600–5000A)
Soft load
Magnum-based
(600–5000A)
Soft load
Magnum-based
(600–5000A)
Soft load
Magnum-based
(600–5000A)
Closed transition
Bypass isolation
Magnum-based
(200–5000A)
Closed transition
Bypass isolation
Magnum-based
(200–5000A)
Closed transition
Bypass isolation
Magnum-based
(200–5000A)
Closed transition
Bypass isolation
Magnum-based
(200–5000A)
Closed transition
Bypass isolation
Magnum-based
(200–5000A)
Closed transition
Bypass isolation
Magnum-based
(200–5000A)
Closed transition
Bypass isolation
Magnum-based
(200–5000A)
Closed transition
Bypass isolation
Contactor-based
(100–1200A)
Closed transition
Bypass isolation
Contactor-based
(100–1200A)
Closed transition
Bypass isolation
Contactor-based
(100–1200A)
Closed transition
Bypass isolation
Contactor-based
(100–1200A)
Closed transition
Bypass isolation
Contactor-based
(100–1200A)
Closed transition
Bypass isolation
Contactor-based
(100–1200A)
Closed transition
Bypass isolation
Contactor-based
(100–1200A)
Closed transition
Magnum-based
(200–5000A)
Closed transition
Magnum-based
(200–5000A)
Closed transition
Magnum-based
(200–5000A)
Closed transition
Magnum-based
(200–5000A)
Closed transition
Magnum-based
(200–5000A)
Closed transition
Magnum-based
(200–5000A)
Closed transition
Magnum-based
(200–5000A)
Closed transition
Contactor-based
(40–1200A)
Delayed transition
Breaker-based
(30–5000A)
Delayed transition
Contactor-based
(40–1200A)
Open transition
Magnum-based
(200–5000A)
Closed transition
Contactor-based
(40–1200A)
Delayed transition
Breaker-based
(30–5000A)
Delayed transition
Contactor-based
(40–1200A)
Open transition
Magnum-based
(200–5000A)
Closed transition
Contactor-based
(40–1200A)
Delayed transition
Breaker-based
(30–5000A)
Delayed transition
Contactor-based
(40–1200A)
Open transition
Magnum-based
(200–5000A)
Closed transition
Contactor-based
(40–1200A)
Delayed transition
Breaker-based
(30–5000A)
Delayed transition
Contactor-based
(40–1200A)
Open transition
Magnum-based
(200–5000A)
Closed transition
Contactor-based
(40–1200A)
Delayed transition
Breaker-based
(30–5000A)
Delayed transition
Contactor-based
(40–1200A)
Open transition
Magnum-based
(200–5000A)
Closed transition
Contactor-based
(40–1200A)
—
Closed transition
Contactor-based
(40–1200A)
—
—
—
—
—
Open transition
Breaker-based
(30–1000A)
Open transition
Contactor-based
(40–1200A)
Non-auto
Magnum-based
(200–5000A)
Manual or non-auto
Breaker-based
(30–1000A)
Open transition
Breaker-based
(30–1000A)
Open transition
Contactor-based
(40–1200A)
Non-auto
Magnum-based
(200–5000A)
Manual or non-auto
Breaker-based
(30–1000A)
Open transition
Breaker-based
(30–1000A)
Open transition
Contactor-based
(40–1200A)
—
Open transition
Breaker-based
(30–1000A)
Open transition
Contactor-based
(40–1200A)
—
Open transition
Breaker-based
(30–1000A)
Open transition
Contactor-based
(40–1200A)
—
—
—
—
—
—
—
—
—
—
—
—
Maintenance bypass
Breaker-based
(100–1000A)
Maintenance bypass
Breaker-based
(100–1000A)
Maintenance bypass
Breaker-based
(100–1000A)
Maintenance bypass
Breaker-based
(100–1000A)
Maintenance bypass
Breaker-based
(100–1000A)
Maintenance bypass
Breaker-based
(100–1000A)
Maintenance bypass
Breaker-based
(100–1000A)
EATON CORPORATION Breaker-based transfer switches 
7
8
EATON CORPORATION Breaker-based transfer switches 
Breaker-based transfer switches
Switch type—automatic open transition
Product description
•
Switch position indication
Eaton’s breaker-based transfer
switches are designed for
a variety of standby power
applications for critical loads.
•
Source availability indication
•
Source 1 and 2
auxiliary contacts
•
Mimic diagram
•
Programmable plant exerciser
•
Safe manual operation under
full load with permanently
affixed operating handle
•
System test pushbutton
•
Load shed from emergency
Electrical ratings
Wall-Mount
ATS With
ATC-300
Controller
•
Molded-case and
circuit breaker 30–1000A
•
100% rated switches
•
Two-, three- or four-pole
•
Up to 600 Vac, 50/60 Hz
•
NEMA 1, 3R, 12, open
•
CSA C22.2 No. 178
•
Suitable for service entrance
•
Integral overcurrent protection
Industrial design highlights
•
2- or 4-position test switch
•
Double-throw,
mechanically interlocked
transfer mechanism
•
Multiple meter
options available
•
•
High withstand and
closing ratings
Selectable automatic or
non-automatic operation
•
Space heaters
•
UL 1008
•
Load sequencing contacts
•
100% rated switches
•
Surge suppression
•
Remote communications
•
Controller availability:
Features
Standard features
•
•
Wall-Mount ATS with ATC-300 Controller
UL 1008 Withstand and Close-On Ratings (kA)
UL 1008 Three-Cycle
“Any Breaker” Rating
Voltage and frequency sensing
Multiple field-programmable
time delays
•
ATC-100
•
ATC-300
•
ATC-600
Molded-Case Transfer Switches—Dimensions in Inches (mm)
Rating When Used
with Upstream Fuse
Switch
Rating
Amperes
240 Vac
480 Vac
600 Vac
Maximum
Fuse Rating
Fuse
Type
600 Vac
30–100
150
150–225
225
300
400
600
800
1000
100
1900
100
100
100
100
100
65
65
65
65
65 (240 Vac)
65
65
65
65 1
50 1
50 1
25
25
25
25
25
25
25
25
25
200
400
400
400
400
600
1200
1600
1600
J, T
J, T
J, T
J, T
J, T
J, T
J, T
L
L
200
200
200
200
200
200
200
200
200
A Four-pole 480 Vac are rated 35 kA.
Optional features
Switch
Rating
Amperes
Switch
Type
Enclosure
A (Height
Enclosure
B (Width)
Enclosure
C (Depth)
Weight
in lbs
(kg)
30–100
150–225
30–100
150
150–225
150–225
150
400
600
600
800
800–1000
HFD 2
HFD 2
HFD 3
HFD 3
HFD 2
HKD
HKD
HLD
HLD 2
HMDL
HMDL 2
HNB
47.74 (1212.6)
47.74 (1212.6)
47.74 (1212.6)
47.74 (1212.6)
35.61 (904.5)
48.00 (1219.2)
56.00 (1422.4)
53.00 (1346.2)
64.00 (1625.6)
76.74 (1949.2)
76.74 (1949.2)
76.74 (1949.2)
20.81 (528.6)
20.81 (528.6)
20.81 (528.6)
20.81 (528.6)
20.06 (509.5)
20.81 (528.6)
20.81 (528.6)
25.81 (655.6)
25.81 (655.6)
25.81 (655.6)
25.81 (655.6)
25.81 (655.6)
17.22 (437.4)
17.22 (437.4)
17.22 (437.4)
17.22 (437.4)
13.34 (338.8)
18.40 (467.4)
18.40 (467.4)
18.40 (467.4)
18.40 (467.4)
19.50 (495.3)
19.50 (495.3)
19.50 (495.3)
232 (105)
232 (105)
240 (190)
240 (190)
150 (68)
305 (138)
295 (134)
425 (193)
475 (214)
480 (218)
510 (232)
540 (245)
B 240/120V, single-phase, three-wire or 208V, three-phase, four-wire systems only.
C With multi-tap voltage selection panel.
EATON CORPORATION Breaker-based transfer switches 
9
10
EATON CORPORATION Breaker-based transfer switches 
Breaker-based transfer switches
Manual and non-automatic
Electrical ratings
Electrical ratings
•
40–1000A
•
40–1000A
•
Two-, three- or four-pole
•
Two-, three- or four-pole
•
100% rated
•
100% rated
•
NEMA 1, 3R, 4, 4X, 12
or open
•
NEMA 1, 3R, 4, 4X, 12
or open
Industrial design highlights
Molded-case switch power
contact assemblies
Positive mechanical and
electrical interlocking
•
Positive mechanical
interlocking
•
Permanently affixed
manual operating handle
•
Permanently affixed manual
operating handle
•
Pushbutton operation
•
Service entrance option
•
100% rated switches
•
UL 1008
•
100% rated switches
•
UL 1008
Manual Wall-Mount Transfer Switch
Non-Automatic Wall-Mount
Features
Manual molded-case
switches
Product description
Eaton’s breaker-based manually
operated transfer switches are
designed for a variety of standby
power applications for critical
loads. In the event of a primary
power source interruption, the
user can manually transfer
the load circuits to the standby
power source.
Non-automatic
molded-case switches
•
Positive mechanical
interlocking
•
Deadfront
•
Permanently mounted manual operating handle
•
Optional space heaters
•
Manually initiated,
manually operated
•
Controller availability:
•
No controller provided
UL 1008 Withstand and Close-On Ratings (kA)
UL 1008 Three-Cycle
“Any Breaker” Rating
Features
•
High withstand, totally
enclosed for maximum
arc suppression and isolation
during power transfer.
•
Optional trip units offer
system overcurrent protection.
•
Optional space heaters
•
Deadfront
•
Manually initiated,
electrically operated
•
Controller availability:
Product description
Eaton’s breaker-based
non-automatic transfer switches
are designed for a variety of
standby power applications for
critical loads. Non-automatic
transfer switches are used in
applications where a manually
initiated transfer is desirable.
Even though the transfer is
manually initiated, the actual
transfer is electrically operated
from a door mounted pushbutton.
•
No controller provided,
motor operator only
Molded-Case Transfer Switches—Dimensions in Inches (mm)
Rating When Used
with Upstream Fuse
Switch
Rating
Amperes
240 Vac
480 Vac
600 Vac
Maximum
Fuse Rating
Fuse
Type
600 Vac
30–100
150
150–225
225
300
400
600
800
1000
100
1900
100
100
100
100
100
65
65
65
65
65 (240 Vac)
65
65
65
65 1
50 1
50 1
25
25
25
25
25
25
25
25
25
200
400
400
400
400
600
1200
1600
1600
J, T
J, T
J, T
J, T
J, T
J, T
J, T
L
L
200
200
200
200
200
200
200
200
200
A Four-pole 480 Vac are rated 35 kA.
Industrial design highlights
•
•
Switch
Rating
Amperes
Switch
Type
Enclosure
A (Height
Enclosure
B (Width)
Enclosure
C (Depth)
Weight
in lbs
(kg)
30–100
150–225
30–100
150
150–225
150–225
150
400
600
600
800
800–1000
HFD 2
HFD 2
HFD 3
HFD 3
HFD 2
HKD
HKD
HLD
HLD 2
HMDL
HMDL 2
HNB
47.74 (1212.6)
47.74 (1212.6)
47.74 (1212.6)
47.74 (1212.6)
35.61 (904.5)
48.00 (1219.2)
56.00 (1422.4)
53.00 (1346.2)
64.00 (1625.6)
76.74 (1949.2)
76.74 (1949.2)
76.74 (1949.2)
20.81 (528.6)
20.81 (528.6)
20.81 (528.6)
20.81 (528.6)
20.06 (509.5)
20.81 (528.6)
20.81 (528.6)
25.81 (655.6)
25.81 (655.6)
25.81 (655.6)
25.81 (655.6)
25.81 (655.6)
17.22 (437.4)
17.22 (437.4)
17.22 (437.4)
17.22 (437.4)
13.34 (338.8)
18.40 (467.4)
18.40 (467.4)
18.40 (467.4)
18.40 (467.4)
19.50 (495.3)
19.50 (495.3)
19.50 (495.3)
232 (105)
232 (105)
240 (190)
240 (190)
150 (68)
305 (138)
295 (134)
425 (193)
475 (214)
480 (218)
510 (232)
540 (245)
B 240/120V, single-phase, three-wire or 208V, three-phase, four-wire systems only.
C With multi-tap voltage selection panel.
EATON CORPORATION Breaker-based transfer switches 
11
12
EATON CORPORATION Breaker-based transfer switches 
Breaker-based transfer switches
Maintenance bypass
Product description
Features
The maintenance bypass switch
consists of two molded-case
switches interconnected by
a unidirectional, motor-driven
transfer mechanism to achieve
closed transition (make-beforebreak) switching between the
power supply originating from
the load side of the UPS equipment (Normal) and directly
from the utility power supply
(Bypass) originating upstream
of the UPS equipment. Local
operation and status are provided on the door-mounted
device panel. Electrical operation
of the switch is inhibited by the lockout contact supplied
from the UPS logic.
•
Make-before-break
electrical operation
•
Lock-out circuit to be
wired into the UPS
bypass authorization
•
Pilot device to show
“Lockout” enabled
•
Pilot devices to show
UPS position “Normal”
and “Bypassed”
•
Manually initiated
electrical operation
•
Solid neutral connections
Incoming
from
Switchboard
UPS
Input Breaker
Electrical ratings
Maintenance Bypass Switch
•
Molded-case switch
100–1000A
•
Two-, three- or four-pole
•
Up to 600 Vac
•
60 Hz
•
NEMA 1, 3R, 4, 4X, 12, open
UPS
System
MBH
Industrial Design Highlights
Standard Withstand, Closing and Interrupting Ratings (kA) 1
Ratings When Used with
Upstream Circuit Breaker
Transfer
Switch
Rating
Amperes
Suggested
Breaker
Rating 2
240V 480V
100
100
100
150
225
150
225
300
400
600
800
1000
•
UL 1008
•
100% rated switch
Computer
Loads
Lockout
Circuit
Maintenance Bypass Application
Drawing
Rating When Used with
Upstream Fuse
NEMA 1 Enclosure Dimensions in Inches (mm)
600V
Maximum
Fuse
Rating
Fuse
Type
480V
65
25
200
J, T
200
100
100
65
65
25
25
400
1400
J, T
J, T
200
200
300
100
65
25
400
J, T 2
200
400
600
800
1000
65
65
65
65
35
50
50
50
25
25
25
25
600
800/1200
1200/1600
1600
J, T
J, T
L
L
200
100/200
100/200
200
Ampere
Rating
Height
Width
Depth
Weight in
lbs (kg)
100–150
225–400
600–1200
24.50 (622.3)
37.50 (952.5)
51.50 (1308.1)
22.88 (581.2)
38.88 (987.6)
38.88 (987.6)
10.28 (261.1)
10.28 (261.1)
17.78 (451.6)
232 (105.3)
232 (105.3)
540 (245.2)
1 Tested in accordance with UL 1008.
2 For maximum breaker rating in circuits where the transfer switch is evaluated as a “motor branch
circuit conductor,” refer to the NEC Section 430.25 for sizing.
3 Also can use Class RK5 fuse with 100 kA rating.
Note: To attain the maximum rating shown in the chart, when protected by an upstream breaker,
the upstream device must have an equivalent interrupting rating.
EATON CORPORATION Breaker-based transfer switches 
13
14
EATON CORPORATION Breaker-based transfer switches 
Breaker-based transfer switches
Service entrance rated
Benefits
•
All installation loads are
protected against extended
power loss
•
Lockable disconnect
position permits safe
downstream maintenance
•
Eliminates need for separate
upstream protective and
service disconnect devices
•
Combined service disconnect,
overcurrent protection and
ATS functions substantially
reduce overall equipment
and installation costs, and
save space
•
•
Fewer components and power
interconnections maximize
circuit integrity and minimize
maintenance requirements
Quick restoration of circuit
after a trip (versus a fused
circuit requiring fuse availability)
•
Trip on a fault prohibits
transfer to emergency source
•
Fused circuit allows testing
of switch by simulating a
true power failure
Typical Wall-Mount SE Rated Switch
With Eaton’s service
entrance rated transfer
switches, installation can
be made directly at the
point of service entrance—
while simultaneously
eliminating the need for
separate upstream fault
protection and their respective
power interconnections.
Features
Service Entrance Label
Conventional approach
•
Automatic transfer switch
•
Separate generator breaker
Separate generator
breaker enclosure
Separate service entrance
disconnect
•
UL 1008 service entrance listed transfer switch
•
•
Service disconnect
“both off” capability
•
Integral overcurrent protection
•
•
•
Lockout (when in
disconnected position only)
•
Indication of service
disconnect
•
Integrated design
•
Disconnecting neutral
assembly
•
•
Ground fault protection
capability—all ratings
(Required by code on ratings
480V and 1000A or higher)
Keyed service entrance switch
Separate service entrance
disconnect enclosure
•
Power cable/bus
interconnections
•
Installation of the
separate components
•
Additional space requirement
•
Added maintenance
•
UL 891 compliance
Utility Service
Service
Disconnect
G
Generator
Breaker
ATS
Load
Conventional Approach
Eaton approach
Eaton’s approach uses a
breaker-based automatic transfer switch that is easily applied
to service entrance applications
by adding an overcurrent trip to
the switch and then including
the service entrance option.
This means that the combined
service entrance rated ATS is
installed directly at the point of
service entrance.
•
Transfer switch with
service entrance rating
•
Single enclosure
•
Reduced power cable/bus
interconnections
•
Reduced space requirements
•
UL 1008 compliance
Utility Service
Service
Disconnect
G
Generator
Breaker
ATS
Load
Eaton Approach
EATON CORPORATION Breaker-based transfer switches 
15
Breaker-based transfer switches
Controller features
Design highlights
•
Mimic diagram with source
available and connected
LED indications
•
Field-selectable fixed
time delays
•
Permits system testing via a
front screen test pushbutton
•
Complies with
UL 1008/CSA 22.2-178
•
Generator Test Selectable—
Off, 7, 14, 28-day interval,
15-minute run time
ATC-300 controller
General description
From installation to programming to usage, the ATC-300
open transition controller
was designed with operational
simplicity in mind. The userfriendly front panel interface
simplifies routine operation,
programming, data presentation
and setting adjustments. An
LCD-based display provides the
flexibility of a back-lit display
for enhanced visibility.
ATC-600 controller
General description
The ATC-600 open transition
controller was designed
with operational simplicity
in mind. The user-friendly front
panel interface simplifies
routine operation, programming,
data presentation and setting
adjustments. An LCD-based
display provides the flexibility
of a back-lit display for
enhanced visibility.
Design highlights
•
LCD-based display for
programming, system
diagnostic and
Help Message display
•
Mimic diagram with source
available and connected
LED indications
•
Stores customer/factory
established parameters in
nonvolatile memory
•
Field-programmable
time delays
•
Displays real time and
historical information with a
time-stamped history log
•
Permits system testing via a
front screen test pushbutton
•
Programmable plant
exerciser—OFF, 7-day interval
selectable run times
•
Communicate via Modbus�
communication protocol
•
Complies with
UL 1008/CSA 22.2-178
•
Load monitoring, delayed,
in-phase and closed transition
Design highlights
•
Wall-Mount Design Showing Optional Controllers Available
Product Description
The automatic transfer switch
controller is a key component
within the automatic transfer
switch. It provides the intelligence to sense the proper
conditions to initiate a transfer
and a retransfer of the contactor.
Eaton’s automatic transfer
switches come with the design
flexibility of being applied with
one of three controllers. All
three controllers provide the
basic functions needed to
perform an automatic transfer.
16
ATC-100 controller
General description
The ATC-100 controller was
designed as a multi-function
microprocessor open transition
controller with simplified
customer settings. The front
panel interface displays source
availability and connection status,
as well as convenient engine
start and test buttons. Controller
parameters are set via jumpers
on the printed circuit board.
EATON CORPORATION Breaker-based transfer switches 
•
LCD-based display for
programming, system
diagnostic and
Help Message display
Mimic diagram with
source available and
connected LED indications
•
Stores customer/factory
established parameters in
nonvolatile memory
•
Field-programmable
time delays
•
Displays real time and
historical information with a
time-stamped history log
•
Permits system testing via a
front screen test pushbutton
•
Programmable plant
exerciser—OFF, daily,
7, 14, 28-day interval
programmable run times
•
Complies with
UL 1008/CSA 22.2-178
Automatic Transfer Switch Controllers
Description
ATC-100
ATC-300
ATC-600
System Application Voltage
Voltage Specifications
Voltage measurements of:
Voltage measurement range
Operating Power
Frequency Specifications
Frequency measurements of:
Frequency measurement range
Environmental Specifications
Operating temperature range
Storage temperature range
Operating Humidity (Noncondensing)
Operating Environment
120/240V, 208V single-phase
Up to 600 Vac
Up to 600 Vac
Source 1 and 2
120–480 Vac
95–145 Vac
Source 1 and 2—VAB, VBC and VCA
0–790 Vac rms
65–145 Vac
Source 1, 2 and Load—VAB, VBC and VCA
0–700 Vac rms
65–145 Vac
Source 2
50–60 Hz
Source 1 and 2
40–70 Hz
Source 1 and 2
40–80 Hz
–20 to 70ºC
–30 to 85ºC
0 to 95% relative humidity (noncondensing)
Resistant to ammonia, methane, nitrogen,
hydrogen and hydrocarbons
–20 to 70ºC
–30 to 85ºC
0 to 95% relative humidity (noncondensing)
Resistant to ammonia, methane, nitrogen,
hydrogen and hydrocarbons
–20 to 70ºC
–30 to 85ºC
0 to 90% relative humidity (noncondensing)
Resistant to ammonia, methane, nitrogen,
hydrogen and hydrocarbons
Front Panel Indication
Mimic diagram with LED indication
Unit status. Source 1 and 2—available and Unit status. Source 1 and 2—available and
connected (5 total)
connected (5 total)
Main display
Display language
Communications Capable
Enclosure Compatibility
Programming Selections
Time delay normal to emergency
Time delay emergency to normal
Time delay engine cooldown
Time delay engine start
Time delay neutral
N/A
N/A
N/A
NEMA 1 and 3R
LCD-based display
English, French
N/A
NEMA 1, 12 and 3R, UV-resistant faceplate
Selectable 2 or 15 seconds
5 minutes—fixed
1 minute—fixed
3 seconds—fixed
N/A
0–1800 seconds
0–1800 seconds
0–1800 seconds
0–120 seconds
0–120 seconds
Time delay Source 2 fail
Time delay voltage unbalance
Voltage unbalance three-phase
Percent of unbalanced voltage dropout
Phase reversal three-phase
In-phase
Load sequencing
Pre-transfer signal
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
0–6 seconds
10–30 seconds
0 or 1 (1 = enabled)
5%–20% (DO) dropout –2% to 3% (PU)
OFF, ABC, CBA
0 or 1 (1 = Enabled)
N/A
1–120 seconds (Form C contact)
Plant exerciser
Selectable day, OFF, 7, 14, 28-day interval,
15 minutes run time, no load
N/A
N/A
N/A
N/A
Utility/generator or dual utility
Selectable—OFF, daily or 7, 14, 28-day
intervals, 0–600 minutes, load or no load
N/A
N/A
N/A
0 or 1 (1 = Enabled)
Utility/generator or dual utility
Preferred source selection
Commitment to transfer in TDNE
Re-transfer mode
Auto daylight saving time adjustment
System selection
Automatic, test and program mode.
Source 1 and 2—available, connected
and preferred. Load energized (10 total)
LED display
English
PONI/INCOM
NEMA 1, 12, 3R and 4X UV-resistant faceplate
0–1800 seconds
0–1800 seconds
0–1800 seconds
0–120 seconds
0–120 seconds or based on load voltage
decay of 2%–30% of nominal
0–6 seconds
N/A
—
N/A
N/A
N/A
Up to 10 devices (via sub-network)
0–120 seconds up to 10 devices
(via sub-network)
Selectable—disabled or 7 day interval,
0–600 minutes, load or no load
Source 1 or 2 or none
Enabled or disabled
Automatic or manual
—
Utility/generator or dual utility or
dual generator
NNote: Features are order-specific. Not all features are supplied as standard.
EATON CORPORATION Breaker-based transfer switches 
17
Breaker-based transfer switches
Ordering information and basic components
Industrial Molded-Case Transfer Switch Catalog Numbering System
AT V 3 KD A 3 0400 X S U
Type
AT = Automatic
MT= Manual
NT = NonAutomatic
MB= Maintenance
Bypass
Orientation
C = Horizontal
V = Vertical
Logic
1 = ATC-100
3 = ATC-300
I = ATC-600
X = No Logic
E = Electromechanical
Amperes
Frame Size
(Ampheres)
Molded-case
device 1
FD= 30–150
KD= 225–300
LD= 400
MD= 600
NB= 800–100
Switch
A = S1 (MCS) S2 (MCS)
B = S1 (MCB) S2 (MCB)
C = S1 (MCB) S2 (MCS)
D = S1 (MCS) S2 (MCB)
Number of Poles
2 = Two-pole
3 = Three-pole
4 = Four-pole
0030 = 30A
0070 = 70A
0100 = 100A
0150 = 150A
0200 = 200A
0225 = 225A
0300 = 260A
0400 = 400A
0600 = 600A
0800 = 800A
1000 = 1000A
1200 = 1200A
Voltage
A=
B=
E =
G=
H=
K =
M=
N=
O=
W=
X =
Z =
120V, 60 Hz
208V, 60 Hz
600V, 60 Hz
220V, 50/60 Hz
380V, 50 Hz
600V, 50 Hz
230V, 50 Hz
401V, 50 Hz
415V, 50 Hz
240V, 60 Hz
480V, 60 Hz
365V, 50 Hz
1 Wall-Mount
Enclosure
K = Open
S = NEMA 1
J = NEMA 12
R = NEMA 3R
Certification
U = UL listed
R = UL recognized
X = No listing
Breaker-Based Design
Source 1 and Load Power
Cable Connections
Control Service Disconnect
(Service Equipment Rated
Switches Only)
Surge Protective Device
(SPD) (Optional)
Automatic Transfer Controller (ATC-300)
• Monitors Power Sources
• Initiates Power Transfers
Customer Control Connections
Permanently Affixed Manual
Transfer Handle Provides Safe
Manual Transfer Under Full Load
Service Disconnect Switch
(Keyed) (Service Equipment
Rated Switches Only)
Power Switching Panel
(With Deadfront Cover Installed)
Transformer Panel
• Steps Line Power Down to 120 Vac
for Logic and Electrical Operator
• Available Multi-Tap Voltage Selector
Source 2 Power Cable Connections
Space Heater (Optional)
Typical Wall-Mount ATS with Service Entrance Rating
18
EATON CORPORATION Breaker-based transfer switches 
Breaker-based transfer switches
Integrated solutions
Integrated solutions
Minimize initial equipment costs,
reduce installation time and
increase system reliability. These
are the goals of all involved in
placing electrical distribution
equipment in service—from the
design engineer, to the electrical
contractor, and especially with
the end user of the equipment.
Eaton believes the transfer
switch equipment is an
integral part of the distribution
equipment. This fundamental
belief is why Eaton offers various
types of transfer switches for
the design engineer, electrical
contractor and the user to
choose from. Eaton offers
contactor-based, molded-case
and circuit breaker style switches.
All Eaton transfer switches
are designed to meet the
requirements set forth by
UL 1008; however, all transfer
switches are not created equal.
You can be assured of safe
and reliable operation from all
types of transfer switches that
Eaton offers.
Switchboard Lineup with Integrated Breaker-Based Design ATS
Integrated solutions may come
directly from one of the Eaton
manufacturing plants or take
advantage of the extensive
network of regional Satellite
plants located across the country.
The plants specialize in providing
a multitude of integrated
solutions for requiring fast
service needs. Highly trained
and experienced personnel will
manage your order and ensure
that you receive on-time delivery
of high-quality equipment that
meter your specifications.
For more information, contact
your local Eaton representative
or authorized distributor.
Satellite Facility Locations
EATON CORPORATION Breaker-based transfer switches 
19
Eaton’s Electrical Sector is
a global leader in power
distribution, power quality,
control and automation, and
monitoring products. When
combined with Eaton’s full-scale
engineering services, these
products provide customerdriven PowerChainE solutions
to serve the power system
needs of the data center,
industrial, institutional, public
sector, utility, commercial,
residential, IT, mission critical,
alternative energy and OEM
markets worldwide.
PowerChain solutions help
enterprises achieve sustainable
and competitive advantages
through proactive management
of the power system as a
strategic, integrated asset
throughout its life cycle,
resulting in enhanced safety,
greater reliability and energy
efficiency. For more information,
visit www.eaton.com/electrical.
Eaton Corporation
Electrical Sector
1111 Superior Ave.
Cleveland, OH 44114
United States
877-ETN-CARE (877-386-2273)
Eaton.com
© 2011 Eaton Corporation
All Rights Reserved
Printed in USA
Publication No. BR01602002E / Z10439
February 2011
PowerChain Management is a registered
trademark of Eaton Corporation.
All other trademarks are property of their
respective owners.