Generac Power Systems RXSW400A3CUL User manual

Owner’s Manual
For
Automatic Transfer Switch
400 Amp, Service Entrance
MODEL NUMBER: RXSW400A3CUL
SERIAL NUMBER: _________________________
DATE PURCHASED:________________________
Register your Generac product at:
WWW.GENERAC.COM
1-888-GENERAC
(888-436-3722)
Para español , visita: http://www.generac.com/service-support/product-support-lookup
Pour le français, visiter : http://www.generac.com/service-support/product-support-lookup
SAVE THIS MANUAL FOR FUTURE REFERENCE
(000209b)
WARNING
Loss of life. This product is not intended to
be used in a critical life support application.
Failure to adhere to this warning could result
in death or serious injury.

ii Automatic Transfer Switch Owner’s Manual
(000393a)
WARNING
CANCER AND REPRODUCTIVE HARM
www.P65Warnings.ca.gov.

Automatic Transfer Switch Owner’s Manual iii
Section 1: Introduction and Safety
Introduction ..........................................................1
Read This Manual Thoroughly ....................................1
Safety Rules .........................................................1
Electrical Hazards ................................................1
General Hazards ..................................................2
Section 2: General Information
Unpacking ............................................................5
Equipment Description .......................................5
Transfer Switch Mechanism ........................................5
Utility Service Circuit Breaker ......................................5
Transfer Switch Data Decal ................................6
Transfer Switch Enclosure .................................6
Safe Use of Transfer Switch ...............................6
Load Management Options .................................6
Smart A/C Module (SACM) .........................................6
Smart Management Module (SMM) ............................7
Application Considerations ..........................................7
Section 3: Installation
Introduction to Installation .................................9
Mounting ...............................................................9
Open Enclosure ...................................................9
Connecting Power Source and Generator
Power Supply ...............................................10
Connecting Start Circuit Wires .........................11
Connecting SACM .............................................11
Control of Air Conditioner Load .................................11
Auxiliary Contacts .............................................13
Fault Current Label ............................................13
Section 4: Operation
Functional Tests and Adjustments ..................15
Manual Operation ..............................................15
Close to Normal Source Side ....................................16
Close to Standby Source Side ..................................16
Return to Normal Source Side ..................................16
Voltage Checks ..................................................16
Utility Voltage Checks ...............................................16
Generator Voltage Checks ........................................16
Generator Tests Under Load ............................ 17
Checking Automatic Operation ........................ 17
Installation Summary ........................................ 17
Shutting Generator Down While
Under Load .................................................. 17
Shutting Generator Down To Perform
Maintenance ................................................ 18
Testing The SACM ............................................. 18
SACM Fuse Service ........................................... 18
Testing The SMM ............................................... 18
Section 5: Drawings and Diagrams
Installation Drawing .......................................... 19
No. 0K2438-A 400A Service Entrance Rated ...........19
Interconnection Drawing .................................. 20
No. 10000041110 (Part 1 of 2)—Liquid-Cooled
Generator .........................................................20
No. 10000041110 (Part 2 of 2)—Air-Cooled
Generator .........................................................21
Schematic and Wiring Diagram ....................... 22
No. 10000041100 (Part 1 of 2)—Schematic
Diagram ............................................................22
No. 10000041100 (Part 2 of 2)—Wiring Diagram .....23
Table of Contents

iv Automatic Transfer Switch Owner’s Manual
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Introduction and Safety
Automatic Transfer Switch Owner’s Manual 1
Section 1: Introduction and Safety
Introduction
Thank you for purchasing a Generac Power Systems Inc.
product. This unit has been designed to provide high
performance, efficient operation, and years of use when
maintained properly.
Read This Manual Thoroughly
If any section of this manual is not understood, contact
the nearest Independent Authorized Service Dealer
(IASD) or Generac Customer Service at 1-888-436-3722
(1-888-GENERAC), or visit www.generac.com for start-
ing, operating, and servicing procedures. The owner is
responsible for proper maintenance and safe use of the
unit.
SAVE THESE INSTRUCTIONS for future reference. This
manual contains important instructions that must be fol-
lowed during placement, operation, and maintenance of
the unit and its components. Always supply this manual
to any individual that will use this unit.
The information in this manual is accurate based on
products produced at the time of publication. The manu-
facturer reserves the right to make technical updates,
corrections, and product revisions at any time without
notice.
Safety Rules
The manufacturer cannot anticipate every possible cir-
cumstance that might involve a hazard. The alerts in this
manual, and on tags and decals affixed to the unit, are
not all inclusive. If using a procedure, work method, or
operating technique that the manufacturer does not spe-
cifically recommend, verify that it is safe for others and
does not render the equipment unsafe.
Throughout this publication, and on tags and decals
affixed to the unit, DANGER, WARNING, CAUTION, and
NOTE blocks are used to alert personnel to special
instructions about a particular operation that may be
hazardous if performed incorrectly or carelessly. Observe
them carefully. Alert definitions are as follows:
NOTE: Notes contain additional information important to
a procedure and will be found within the regular text of
this manual.
These safety alerts cannot eliminate the hazards that
they indicate. Common sense and strict compliance with
the special instructions while performing the action or
service are essential to preventing accidents.
Electrical Hazards
(000100a)
WARNING
Consult Manual. Read and understand manual
completely before using product. Failure to
completely understand manual and product
could result in death or serious injury.
(000001)
DANGER
Indicates a hazardous situation which, if not avoided,
will result in death or serious injury.
(000002)
WARNING
Indicates a hazardous situation which, if not avoided,
could result in death or serious injury.
(000003)
CAUTION
Indicates a hazardous situation which, if not avoided,
could result in minor or moderate injury.
(000129)
DANGER
Electrocution. High voltage is present at
transfer switch and terminals. Contact with live
terminals will result in death or serious injury.
(000104)
DANGER
Electrocution. Water contact with a power
source, if not avoided, will result in death
or serious injury.
(000145)
DANGER
Electrocution. In the event of electrical accident,
immediately shut power OFF. Use non-conductive
implements to free victim from live conductor. Apply
first aid and get medical help. Failure to do so will
result in death or serious injury.

Introduction and Safety
2Automatic Transfer Switch Owner’s Manual
General Hazards
(000237)
DANGER
Electrical backfeed. Use only approved switchgear to
isolate generator from the normal power source.
Failure to do so will result in death, serious injury,
and equipment damage.
(000195)
DANGER
Electrocution, equipment and property damage.
Handle transfer switches carefully when installing.
Never install a damaged transfer switch. Doing so
could result in death or serious injury, equipment
and property damage.
(000123)
DANGER
Electrocution. Turn utility supply OFF before
working on utility connections of the transfer
switch. Failure to do so will result in death or
serious injury.
(000157)
DANGER
Electrocution. Do not disable or modify the
connection box door safety switch. Doing so
will result in death or serious injury.
Automatic start-up. Disconnect utility power and
render unit inoperable before working on unit.
Failure to do so will result in death or serious injury.
(000191)
DANGER
(000119)
Equipment malfunction. Installing a dirty or damaged
transfer switch will cause equipment malfunction and
will result in death or serious injury.
DANGER
(000155a)
WARNING
Electric shock. Only a trained and licensed electrician
should perform wiring and connections to unit. Failure
to follow proper installation requirements could result in
death, serious injury, and equipment or property damage.
(000120)
CAUTION
Equipment damage. Verify all conductors are tightened
to the factory specified torque value. Failure to do so
could result in damage to the switch base.
(000121)
CAUTION
Equipment damage. Perform functional tests in the
exact order they are presented in the manual.
Failure to do so could result in equipment damage.
(000134a)
CAUTION
Equipment damage. Exceeding rated voltage and
current will damage the auxiliary contacts. Verify
that voltage and current are within specification
before energizing this equipment.
(000237)
DANGER
Electrical backfeed. Use only approved switchgear to
isolate generator from the normal power source.
Failure to do so will result in death, serious injury,
and equipment damage.
(000129)
DANGER
Electrocution. High voltage is present at
transfer switch and terminals. Contact with live
terminals will result in death or serious injury.
(000123)
DANGER
Electrocution. Turn utility supply OFF before
working on utility connections of the transfer
switch. Failure to do so will result in death or
serious injury.
(000104)
DANGER
Electrocution. Water contact with a power
source, if not avoided, will result in death
or serious injury.
(000188)
DANGER
Electrocution. Do not wear jewelry while
working on this equipment. Doing so will
result in death or serious injury.

Introduction and Safety
Automatic Transfer Switch Owner’s Manual 3
IMPORTANT NOTE: See individual unit specifications
for required maintenance and run times pertaining to
use.
•Competent, qualified personnel should install,
operate and service this equipment. Adhere strictly
to local, state and national electrical and building
codes. When using this equipment, comply with
regulations established by the National Electrical
Code (NEC), CSA Standard; the Occupational
Safety and Health Administration (OSHA), or the
local agency for workplace health and safety.
•If working on this equipment while standing on
metal or concrete, place insulative mats over a dry
wood platform. Work on this equipment only while
standing on such insulative mats.
Any voltage measurements should be performed with a
meter that meets UL3111 safety standards, and meets or
exceeds overvoltage class CAT III.
(000213)
DANGER
Electrocution. Only authorized personnel should
access transfer switch interior. Transfer switch
doors should be kept closed and locked. Failure to
do so will result in death or serious injury.
Automatic start-up. Disconnect utility power and
render unit inoperable before working on unit.
Failure to do so will result in death or serious injury.
(000191)
DANGER
(000145)
DANGER
Electrocution. In the event of electrical accident,
immediately shut power OFF. Use non-conductive
implements to free victim from live conductor. Apply
first aid and get medical help. Failure to do so will
result in death or serious injury.
WARNING
Equipment damage. This unit is not intended for use as a
prime power source. It is intended for use as an intermediate
power supply in the event of temporary power outage only.
Doing so could result in death, serious injury, and
equipment damage. (000247a)
WARNING
Risk of injury. Do not operate or service this machine
if not fully alert. Fatigue can impair the ability to service
this equipment and could result in death or serious
injury. (000215)

Introduction and Safety
4Automatic Transfer Switch Owner’s Manual
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General Information
Automatic Transfer Switch Owner’s Manual 5
Section 2: General Information
Unpacking
Carefully unpack the transfer switch. Inspect closely for
any damage that might have occurred during shipment.
The purchaser must file with the carrier any claims for
loss or damage incurred while in transit. Verify that all
parts are included.
Verify that all packing material is completely removed
from the switch prior to installation.
Equipment Description
The automatic transfer switch is used for transferring
electrical load from a utility (normal) power source to a
generator (standby) power source. Such a transfer of
electrical loads occurs automatically when the utility
power source has failed or is substantially reduced and
the generator source voltage and frequency have
reached an acceptable level. The transfer switch pre-
vents electrical feedback between two different power
sources (such as the utility and generator sources) and,
for that reason, codes require it in all standby electric
system installations.
The transfer switch consists of a transfer mechanism,
utility service disconnect circuit breaker (if equipped), a
control relay, a Smart A/C module, fuses, terminal strip,
and fuse holder for connection of sensing wires.
This UL/CUL listed transfer switch has locking provisions
for the utility entry cabinet. In addition, it has a lockout/
tagout provision for the service entrance circuit breaker.
Transfer Switch Mechanism
See Figure 2-1. These switches are used with a single-
phase system, when the single-phase neutral line is to be
connected to a neutral lug and is not to be switched.
Solderless, screw-type terminal lugs are standard.
The conductor size range is as follows:
This transfer switch is suitable for control of motors, elec-
tric discharge lamps, tungsten filament and electric heat-
ing equipment where the sum of motor full load ampere
ratings and the ampere ratings of other loads do not
exceed the ampere rating of the switch and the tungsten
load does not exceed 30% of the switch rating.
This UL listed transfer switch is for use in optional
standby systems only (NEC article 702).
This transfer switch is suitable for use on a circuit
capable of 22,000 rms symmetrical amperes, 240 VAC
maximum.
Figure 2-1. Typical Single-Phase ATS Transfer
Mechanism
Utility Service Circuit Breaker
The utility service circuit breaker is:
Generac, 400AF
•120/240VAC, 400A
•50/60 Hertz
•Wire range: (1) #4-600 MCM or (2) 1/0-250 MCM
(Cu/Al)
•The conductor torque specification is 375 in-lbs
(42.4 Nm).
Switch
Rating Wire Range Conductor Torque Specification
400A
(1) #4-600 MCM
(Cu/Al)
or
(2) 1/0-250 MCM
(Cu/Al)
375 in-lbs (42.4 Nm)
A Utility Lugs (N1 & N2)
B Generator Lugs (E1 & E2)
C Load Lugs (T1 & T2)
000218
A
B
C

General Information
6Automatic Transfer Switch Owner’s Manual
Transfer Switch Data Decal
See Figure 2-2. A data decal is permanently affixed to
the transfer switch enclosure. Use this transfer switch
only with the specific limits shown on the data decal and
on other decals and labels that may be affixed to the
switch. This will prevent damage to equipment and prop-
erty.
Figure 2-2. Data Decal Location
When requesting information or ordering parts for this
equipment, make sure to include all information from the
data decal.
For future reference, record the serial number in the
space provided on the front cover of this manual.
Transfer Switch Enclosure
The standard switch enclosure is a National Electrical
Manufacturer’s Association (NEMA) and UL/CUL 3R
type. UL/CUL and NEMA 3R (indoor/outdoor rated) type
enclosures primarily provide a degree of protection
against falling rain and sleet; are undamaged by the
formation of ice on the enclosure.
Safe Use of Transfer Switch
Before installing, operating or servicing this equipment,
read the Safety Rules carefully. Comply strictly with all
Safety Rules to prevent accidents and/or damage to the
equipment. The manufacturer recommends that a copy
of the Safety Rules be posted near the transfer switch.
Also, be sure to read all instructions and information
found on tags, labels and decals affixed to the
equipment.
The following publications outline the safe use of transfer
switches:
•Canadian Electrical Code CE; CSA C22.1
•NFPA 70E: Standard for Electrical Safety In The
Workplace
•UL/CUL 1008: Standard for Safety—Automatic
Transfer Switches
NOTE: It is essential to use the latest version of any
standard to ensure correct and current information.
Load Management Options
Load management systems are designed to work
together to prevent a generator from being overloaded by
large appliance loads. A Smart A/C Module (SACM) is
standard in these switches. An optional Smart Manage-
ment Module (SMM) is also available.
Smart A/C Module (SACM)
Up to four air conditioner loads can be managed by the
SACM. The SACM manages the loads by “shedding” the
connected loads in the event of a drop in generator fre-
quency (overload). Loads to be “shed” are in four priority
levels on the module.
See Figure 2-3. Priorities A/C 1-4 (A) have connections
for an air conditioner. To control an air conditioner, no
additional equipment is required. Internal normally closed
relays interrupt the 24 VAC thermostat control signal to
disable the air conditioner load.
Figure 2-3. Smart A/C Module (SACM)
008981
(000100a)
WARNING
Consult Manual. Read and understand manual
completely before using product. Failure to
completely understand manual and product
could result in death or serious injury.
1
1
1
1
2
2
2
2
T1N1N2
0 DC GROUND
194 +12 VDC
N1
N2
T1
23 TRANSFER
Replace with Littelfuse 021606.3XHP,
Optifuse FCD-6.3A or
Generac 10000005117 250 vac, 6.3A
®
®
A
B
C
D
004436