Generac Power Systems 04635-0 User manual

Owner’s Manual
GTS “W”Type
Automatic
Transfer Switch
200 Amp, 250 Volts
Model 04635-0
®
POWER SYSTEMS, INC.
This manual should remain with the unit.

Generac®Power Systems, Inc.
Generac cannot possibly anticipate every possible cir
cumstance that might involve a hazard. The warnings
in this manual, and on tags and decals affixed to the
unit are, therefore, not all-inclusive. If using a
procedure, work method or operating technique
Generac does not specifically recommend, ensure
that it is safe for others. Also make sure the
procedure, work method or operating technique
chosen does not render the transfer switch unsafe.
Throughout this publication, and on tags and
decals affixed to the generator, 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.
Their definitions are as follows:
After this heading, read instructions that, if not
strictly complied with, will result in personal
injury, including death, or property damage.
After this heading, read instructions that, if not
strictly complied with, may result in personal injury
or property damage.
After this heading, read instructions that, if not
strictly complied with, could result in damage to
equipment and/or property.
NOTE:
After this heading, read explanatory statements
that require special emphasis.
These safety warnings cannot eliminate the hazards
that they indicate. Common sense and strict
compliance with the special instructions while
performing the service are essential to preventing
accidents.
Four commonly used safety symbols accompany the
DANGER, WARNING and CAUTION blocks. The type
of information each indicates follows:
This symbol points out important safety
information that, if not followed, could endanger
personal safety and/or property of others.
This symbol points out potential explosion hazard.
This symbol points out potential fire hazard.
This symbol points out potential electrical shock
hazard.
GENERAL HAZARDS
• Any AC generator that is used for backup power if
a NORMAL (utility) power source failure occurs,
must be isolated from the NORMAL (utility) power
source by means of an approved transfer switch.
Failure to properly isolate the NORMAL and
STANDBY power sources from each other may
result in injury or death to electric utility workers,
due to backfeed of electrical energy.
• Improper or unauthorized installation, operation,
service or repair of the equipment is extremely
dangerous and may result in death, serious
personal injury, or damage to equipment and/or
personal property.
• Extremely high and dangerous power voltages are
present inside an installed transfer switch. Any
contact with high voltage terminals, contacts or
wires will result in extremely hazardous, and
possibly LETHAL, electric shock. DO NOT WORK
ON THE TRANSFER SWITCH UNTIL ALL POWER
VOLTAGE SUPPLIES TO THE SWITCH HAVE
BEEN POSITIVELY TURNED OFF.
• 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 the National Electrical Code (NEC),
CSA Standard; C22.1 Canadian Electric Code and
Occupational Safety and Health Administration
(OSHA) have established.
• Never handle any kind of electrical device while
standing in water, while barefoot, or while hands
or feet are wet. DANGEROUS ELECTRICAL
SHOCK MAY RESULT.
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DANGER
IMPORTANT SAFETY INSTRUCTIONS
SAVE THESE INSTRUCTIONS. Read the following information carefully before attempting to
install, operate or service this equipment. Also read the instructions and information on tags,
decals, and labels that may be affixed to the transfer switch. Replace any decal or label that
is no longer legible.
DANGER! Connection of a generator to an electrical system normally supplied by an electric
utility shall be by means of suitable transfer equipment so as to isolate the electric system
from utility distribution system when the generator is operating (Article 701 Legally Required
Standby Systems or Article 702 Optional Standby Systems, as applicable). Failure to isolate
electric system by these means may result in damage to generator and may result in injury
or death to utility workers due to backfeed of electrical energy.
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Table of Contents
Generac®Power Systems, Inc. 1
Safety Rules..........................................Inside Front Cover
Section 1 — General Information ..................................2
1.1 Introduction ............................................................2
1.2 Equipment Description ............................................2
1.3 Transfer Switch Data Plate ......................................2
1.4 Transfer Switch Enclosure ......................................2
1.5 Safe Use Of Transfer Switch ....................................2
Section 2 — Installation ....................................................3
2.1 Introduction to Installation ......................................3
2.2 Unpacking ................................................................3
2.3 Mounting ..................................................................3
2.4 Connecting Power Source and Load Lines................3
2.4.1 2-Pole Mechanism ..........................................3
2.5 Connecting Start Circuit Wires ................................4
2.6 Auxiliary Contacts ....................................................4
Section 3 — Operation ......................................................5
3.1 Functional Tests & Adjustments ..............................5
3.2 Manual Operation ....................................................5
3.2.1 Close to Normal Source Side ........................6
3.2.2 Close to Emergency Source Side....................6
3.2.3 Return to Normal Source Side ......................6
3.3 Voltage Checks..........................................................6
3.4 Generator Tests Under Load ....................................7
Section 4 – Mounting Dimensions ................................8
Section 5 – Electrical Data ..............................................9
Section 6 – Exploded Views & Parts Lists ..................12
Section 7 – Warranty ......................................Back Cover
• Because jewelry conducts electricity, wearing it
may cause dangerous electrical shock. Remove all
jewelry (such as rings, watches, bracelets, etc.)
before working on this equipment.
• If work must be done 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.
• Never work on this equipment while physically or
mentally fatigued.
• Keep the transfer switch enclosure door closed and
bolted at all times. Only qualified personnel
should be permitted access to the switch interior.
• In case of an accident caused by electric shock,
immediately shut down the source of electrical
power. If this is not possible, attempt to free the
victim from the live conductor but AVOID DIRECT
CONTACT WITH THE VICTIM. Use a
nonconducting implement, such as a rope or
board, to free the victim from the live conductor. If
the victim is unconscious, apply first aid and get
immediate medical help.
• When an automatic transfer switch is installed for
a standby generator set, the generator engine may
crank and start at any time without warning. To
avoid possible injury that might be caused by such
sudden start-ups, the system’s automatic start
circuit must be disabled before working on or
around the generator or transfer switch. For that
purpose, a SAFETY DISCONNECT is provided
inside the transfer switch. Always set that switch
to its MANUAL position before working on the
equipment. Then place a “DO NOT OPERATE” tag
on the transfer switch and on the generator.
Remove the Negative (Neg) or (–) battery cable.

2 Generac®Power Systems, Inc.
Section 1 — General Information
Generac GTS “W” Type Transfer Switch
1.1 INTRODUCTION
This manual has been prepared especially for the
purpose of familiarizing personnel with the design,
application, installation, operation and servicing of
the applicable equipment. Read the manual carefully
and comply with all instructions. This will help to
prevent accidents or damage to equipment that might
otherwise be caused by carelessness, incorrect
application, or improper procedures.
Every effort has been expended to make sure that the
contents of this manual are both accurate and
current. Generac, however, reserves the right to
change, alter or otherwise improve the product at any
time without prior notice.
1.2 EQUIPMENT DESCRIPTION
The automatic transfer switch is used for
transferring critical electrical load from a UTILITY
(Normal) power source to a EMERGENCY
(STANDBY) power source. Such a transfer of
electrical loads occurs automatically when the
UTILITY power source has failed or is substantially
reduced and the EMERGENCY source voltage and
frequency have reached an acceptable level. The
transfer switch prevents electrical feedback between
two different power sources (such as the UTILITY
and EMERGENCY sources) and, for that reason,
codes require it in all standby electric system
installations.
The transfer switch consists of a solid state
intelligence circuit, a transfer mechanism and a
control panel.
1.3 TRANSFER SWITCH DATA DECAL
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
property.
When requesting information or ordering parts for this
equipment, make sure to include all information from
the DATA DECAL.
Record the Model and Serial numbers in the space
provided below for future reference.
1.4 TRANSFER SWITCH ENCLOSURE
The standard switch enclosure is a National
Electrical Manufacturer’s Association (NEMA) 3R
type. NEMA 3R type enclosures primarily provide a
degree of protection against falling rain and sleet;
undamaged by the formation of ice on the
enclosure.
1.5 SAFE USE OF TRANSFER SWITCH
Before installing, operating or servicing this
equipment, read the SAFETY RULES (inside front
cover) carefully. Comply strictly with all SAFETY
RULES to prevent accidents and/or damage to the
equipment. Generac 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.
Two publications that outline the safe use of transfer
switches are the following:
• NFPA 70; National Electrical Code
• UL 1008, STANDARD FOR SAFETY-AUTOMATIC
TRANSFER SWITCHES
ASSEMBLY #
SERIAL #

Generac®Power Systems, Inc. 3
2.1 INTRODUCTION TO INSTALLATION
This equipment has been wired and tested at the
factory. Installing the switch includes the following
procedures:
• Mounting the enclosure.
• Connecting power source and load leads.
• Connecting the generator start circuit.
• Connecting any auxiliary contact (if needed)
• Installing/connecting any options and accessories.
• Testing functions.
2.2 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.
Check that all packing material is completely
removed from the switch prior to installation.
2.3 MOUNTING
Mounting dimensions for the transfer switch
enclosure are in this manual. Enclosures are
typically wall-mounted. See “Mounting Dimensions”.
Handle transfer switches carefully when
installing. Do not drop the switch. Protect the
switch against impact at all times, and against
construction grit and metal chips. Never
install a transfer switch that has been
damaged.
Install the transfer switch as close as possible to the
electrical loads that are to be connected to it. Mount
the switch vertically to a rigid supporting structure.
To prevent switch distortion, level all mounting
points. If necessary, use washers behind mounting
holes to level the unit.
2.4 CONNECTING POWER SOURCE
AND LOAD LINES
Make sure to turn OFF both the UTILITY
(NORMAL) and EMERGENCY (STANDBY)
power supplies before trying to connect
power source and load lines to the transfer
switch. Supply voltages are extremely high
and dangerous. Contact with such high
voltage power supply lines causes extremely
hazardous, possibly lethal, electrical shock.
Wiring diagrams and electrical schematics are
provided in this manual. Power source and load
connections are made at a transfer mechanism,
inside the switch enclosure.
2.4.1 2-POLE MECHANISM
These switches (Figure 2.1) 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.
Figure 2.1 — Typical 2-Pole Transfer Mechanism
(100 Amp Shown)
Solderless, screw-type terminal lugs are standard.
The conductor size range is as follows:
Conductor sizes must be adequate to handle the
maximum current to which they will be subjected;
based on the 75°C column of tables, charts, etc. used
to size conductors. The installation must comply fully
with all applicable codes, standards and regulations.
Before connecting wiring cables to terminals, remove
any surface oxides from the cable ends with a wire
brush. All power cables should enter the switch next
to transfer mechanism terminals. If ALUMINUM
conductors are used, apply corrosion inhibitor to
conductors. Tighten terminal lugs to the torque
values as noted on the decal located on the inside of
the door. After tightening terminal lugs, carefully wipe
away any excess corrosion inhibitor.
All power cables should enter the switch next to the
transfer mechanism terminals.
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DANGER
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Section 2 — Installation
Generac GTS “W” Type Transfer Switch
Switch Rating Wire Range
200A #4-400 MCM

4 Generac®Power Systems, Inc.
Use a torque wrench to tighten the
conductors, being sure not to overtighten, or
damage to the switch base could occur. If
undertightened, a loose connection would
result, causing excess heat which could
damage the switch base.
Connect power source load conductors to clearly
marked transfer mechanism terminal lugs as follows
1. Connect UTILITY (NORMAL) power source cables
to switch terminals N1, N2.
2. Connect EMERGENCY (STANDBY) source power
cables to transfer switch terminals E1, E2.
3. Connect customer LOAD leads to switch
terminals Load 1, Load 2. (Load 1 and Load 2 are
used with liquid-cooled units only.)
Conductors must be properly supported, of approved
insulative qualities, protected by approved conduit,
and of the correct wire gauge size in accordance with
applicable codes.
Be sure to maintain proper electrical clearance
between live metal parts and grounded metal. Allow
at least 1/2 inch for 100-400 amp circuits; at least
one inch for circuits over 400 amps.
2.5 CONNECTING START CIRCUIT
WIRES
Control system interconnections consist of UTILITY
1 and 2, LOAD 1 and 2 (liquid-cooled units only); and
leads 23 and 194. Control system interconnection
leads must be run in a conduit that is separate from
the AC power lead. Recommended wire gauge sizes
for this wiring depends on the length of the wire, as
recommended below:
2.6 AUXILIARY CONTACTS
If desired, there are Auxiliary Contacts on the
transfer switch to operate customer accessories,
remote advisory lights, or remote annunciator
devices. A suitable power source must be connected
to the COMMON (C) terminal. See Figure 2.3.
Contact operation is shown in the following chart:
NOTE:
Auxiliary Contacts are rated 10 amps at 125 or
250 volts AC. DO NOT EXCEED THE RATED
VOLTAGE AND CURRENT OF THE CONTACTS.
Figure 2.3 – Auxiliary Contacts
Optional
Auxiliary Contact
(Actuated)
Side views shown in Utility position
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Section 2 — Installation
Generac GTS “W” Type Transfer Switch
MAXIMUM WIRE LENGTH RECOMMENDED WIRE
SIZE
460 feet (140m) No. 18 AWG.
461 to 730 feet (223m) No. 16 AWG.
731 to 1,160 feet (354m) No. 14 AWG.
1,161 to 1,850 feet (565m) No. 12 AWG.
Switch Position
Utility Standby
Common to Normally Open Open Closed
Common to Normally Closed Closed Open

Generac®Power Systems, Inc. 5
3.1 FUNCTIONAL TESTS AND
ADJUSTMENTS
Following transfer switch installation and
interconnection, inspect the entire installation
carefully. A competent, qualified electrician
should inspect it. The installation should comply
strictly with all applicable codes, standards, and
regulations. When absolutely certain the
installation is proper and correct, complete a
functional test of the system.
Perform functional tests in the exact order
presented in this manual, or the switch could
be damaged.
IMPORTANT: Before proceeding with functional
tests, read and make sure all instructions and
information in this section is understood. Also read
the information and instructions of labels and decals
affixed to the switch. Note any options or accessories
that might be installed and review their operation.
3.2 MANUAL OPERATION
Do NOT manually transfer under load.
Disconnect transfer switch from all power
sources by approved means, such as a main
circuit breaker(s).
A manual HANDLE is shipped with the transfer
switch. Manual operation must be checked BEFORE
the transfer switch is operated electrically. To check
manual operation, proceed as follows:
1. Turn the generator’s AUTO-OFF-MANUAL switch
to OFF.
2. Turn OFF both UTILITY and EMERGENCY
power supplies to the transfer switch, with
whatever means provided (such as the main line
circuit breakers).
3. Note position of transfer mechanism main
contacts by observing display windows in “A” and
“B” in Figure 3.1 as follows:
• Window “A” ON, Window “B” OFF - LOAD
terminals (T1, T2) are connected to UTILITY
terminals (N1, N2).
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DANGER
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Section 3 — Operation
Generac GTS “W” Type Transfer Switch
Figure 3.1 — Actuating Transfer Switch

6 Generac®Power Systems, Inc.
• Window “A” OFF, Window “B” ON - LOAD
terminals (T1, T2) are connected to
EMERGENCY terminals (E1, E2).
Do not use excessive force when operating
the transfer switch manually or the manual
handle could be damaged.
3.2.1 CLOSE TO NORMAL SOURCE SIDE
Before proceeding, verify the position of the switch by
observing window “A” in Figure 3.1. If window “A”
reads “ON”, the contacts are closed in the NORMAL
position, no further action is required. If it reads
“OFF”, proceed with Step 1.
Step 1: With the handle attached to the actuating
shaft, move handle in the direction of the
arrow on the switch cover until it stops — DO
NOT FORCE. Release handle slowly to allow
the spring in the switch box to relax. “ON”
now appears in Window “A” and “OFF”
appears in Window “B”.
3.2.2 CLOSE TO EMERGENCY SOURCE SIDE
Before proceeding, verify the position of the switch by
observing window “B” in Figure 3.1. If window “B”
reads “ON”, the contacts are closed in the
EMERGENCY (STANDBY) position. No further action
is required. If it reads “OFF”, proceed with Step 1.
Step 1: With the handle attached to the actuating
shaft, move the handle in the direction of the
arrow on the switch cover until it stops - DO
NOT FORCE. Release handle slowly to allow
the spring in the switch box to relax. “OFF”
now appears in Window “A” and “ON” appears
in Window “B”.
3.2.3 RETURN TO NORMAL SOURCE SIDE
Manually actuate switch to return Window “A” to the
“ON” position.
3.3 VOLTAGE CHECKS
1. Turn ON the UTILITY power supply to the
transfer switch with whatever means provided
(such as the UTILITY maim line circuit breaker).
PROCEED WITH CAUTION. THE TRANSFER
SWITCH IS NOW ELECTRICALLY HOT. CONTACT
WITH LIVE TERMINALS RESULTS IN EXTREMELY
HAZARDOUS AND POSSIBLY FATAL
ELECTRICAL SHOCK.
2. With an accurate AC voltmeter, check for correct
voltage.
Single-phase utility supply:
Measure across ATS terminal lugs N1 and N2; N1
to NEUTRAL and N2 to NEUTRAL.
3. When certain that UTILITY supply voltage is
correct and compatible with transfer switch
ratings, turn OFF the UTILITY supply to the
transfer switch.
4. On the generator panel, set the AUTO-OFF-
MANUAL switch to MANUAL position. The
generator should crank and start.
5. Let the generator stabilize and warm up at no-
load for at least five minutes.
6. Set the generator's main circuit breaker (CB1) to
its ON or CLOSED position.
PROCEED WITH CAUTION. GENERATOR
OUTPUT VOLTAGE IS NOW BEING DELIVERED
TO TRANSFER SWITCH TERMINALS. CONTACT
WITH LIVE TERMINALS RESULTS IN EXTREMELY
DANGEROUS AND POSSIBLY FATAL
ELECTRICAL SHOCK.
7. With an accurate AC voltmeter and frequency
meter, check the no-load, voltage and frequency.
Single-phase generator supply:
Measure across ATS terminal lugs E1 to E2; E1
to NEUTRAL and E2 to NEUTRAL.
a. Frequency ......................................60-62 Hz
b. Terminals E1 to E2 ........................240-246 VAC
c. Terminals E1 to NEUTRAL ............120-123 VAC
d. Terminals E2 to NEUTRAL ............120-123 VAC
It will also be necessary to verify that the phase
rotation of the utility matches the phase rotation of
the generator. This can be done by using a phase
rotation indicator.
Failure to do so may result in damage to
certain rotary equipment.
8. Set the generator’s main circuit breaker (CB1) to
its OFF or OPEN position.
9. Set the AUTO-OFF-MANUAL switch to the OFF
position to shut down the generator.
NOTE:
Do NOT proceed until generator AC output voltage
and frequency are correct and within stated limits.
If the no-load voltage is correct but no-load
frequency is incorrect, the engine governed speed
probably requires adjustment. If no-load
frequency is correct but voltage is not, the voltage
regulator may require adjustment.
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DANGER
DANGER
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Section 3 — Operation
Generac GTS “W” Type Transfer Switch

Generac®Power Systems, Inc. 7
3.4 GENERATOR TESTS UNDER LOAD
1. Set the generator's main circuit breaker to its
OFF or OPEN position.
2. Manually actuate the transfer switch main
contacts to their EMERGENCY (STANDBY)
position. Refer to Manual Operation.
3. To start the generator, set the AUTO-OFF-
MANUAL switch to MANUAL. When engine starts,
let it stabilize for a few minutes.
4. Turn the generator's main circuit breaker to its
ON or CLOSED position. The generator now
powers all LOAD circuits. Check generator
operation under load as follows:
• Turn ON electrical loads to the full rated
wattage/amperage capacity of the generator.
DO NOT OVERLOAD.
• With maximum rated load applied, check
voltage and frequency across transfer switch
terminals E1 and E2. Voltage should be
greater than 230 volts; frequency should be
greater than 59 Hz.
• Let the generator run under rated load for at
least 30 minutes. With unit running, listen for
unusual noises, vibration, overheating, etc.,
that might indicate a problem.
5. When checkout under load is complete, set main
circuit breaker of the generator to its OFF or
OPEN position.
6. Let the generator run at no-load for several
minutes. Then, shut down by setting the AUTO-
OFF-MANUAL switch to its OFF position.
7. Move the switch's main contacts back to their
utility position. For example, load connected to
utility power supply. Refer to Manual Operation.
Handle and operating lever of transfer switch
should be in down position.
8. Turn on the utility power supply to transfer
switch, using whatever means provided (such as
a utility main line circuit breaker). The utility
power source now powers the loads.
9. Set the generator's AUTO-OFF-MANUAL switch to
its AUTO position. The system is now set for fully
automatic operation.
Section 3 — Operation
Generac GTS “W” Type Transfer Switch

8 Generac®Power Systems, Inc.
Section 4 — Mounting Dimensions
Generac GTS “W” Type Transfer Switch
Mounting Dimensions – Drawing No. 0D3714-B
180 514
612 490
430
Values are in Millimeters
Note: Diameter of Mounting holes (A) is 6.35 MM
AA
AA