ETC ELTS2 User manual

Part Number: 1096M1210 Rev: B
Released: 2021-07
Emergency Lighting
Transfer System
Model: ELTS2
Installation and User
Operation Manual

To view a list of ETC trademarks and patents, go to etcconnect.com/ip . All other trademarks, both
marked and not marked, are the property of their respective owners.
ETC intends this document, whether printed or electronic, to be provided in its entirety.

Table of Contents i
Table of Contents
Section 1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . .1
Compliance and Standards . . . . . . . . . . . . . . . . . . . . . .1
Warnings and Notice Conventions . . . . . . . . . . . . . . . .1
Contacting ETC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Product Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Type D (Discrete Feed) Overview. . . . . . . . . . . . . . . . . . . . . . . .4
Type M (Main Feed) Overview. . . . . . . . . . . . . . . . . . . . . . . . . .5
Standard Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Product Variants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Section 2 Installation . . . . . . . . . . . . . . . . . . . . . . . . . .8
Installation Requirements . . . . . . . . . . . . . . . . . . . . . . .8
Installation Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Clearance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Electrical Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Sense Feed Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Transfer Switch Specification. . . . . . . . . . . . . . . . . . . . . . . . . .11
Prepare for Installation . . . . . . . . . . . . . . . . . . . . . . . .11
Verify Contents of the Shipping Carton . . . . . . . . . . . . . . . . .11
Parts and Specialty Tools Required . . . . . . . . . . . . . . . . . . . . .11
Cable Specification and Conduit Access . . . . . . . . . . . . . . . . .11
Install the ELTS2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Determine the Installation Location . . . . . . . . . . . . . . . . . . . .14
Install Mounting Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Rough-In Conduit and Cable . . . . . . . . . . . . . . . . . . . . . . . . . .16
Connect Emergency Discrete Inputs for
Type D (Discrete Feed) Unit . . . . . . . . . . . . . . . . . . . . .19
Connect Emergency Discrete Input Wires to the
Terminal Strip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Connect Emergency Mains for
Type M (Main Feed) Unit . . . . . . . . . . . . . . . . . . . . . . .20
Connect Mains Feed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Connect Wiring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Connect Normal Input Wires to the Transfer Switch . . . . . . .21
Connect Load Output Wires to the Terminal Strip. . . . . . . . .22
Connect 120 VAC Sense Power Wiring . . . . . . . . . . . . . . . . . .23
Connect 240 and 277 VAC Sense Power Wiring . . . . . . . . . . .24
Connect Fire Alarm and Remote Station Wiring . . . . . . . . . .25

ii ELTS2 Installation and User Operation Manual
Power Up and Check System . . . . . . . . . . . . . . . . . . . .26
Power Up. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Check System Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Manual Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Automatic Operation Test . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Section 3 Operation. . . . . . . . . . . . . . . . . . . . . . . . . .29
How the ELTS2 Works . . . . . . . . . . . . . . . . . . . . . . . . .29
How the ELTS2 Determines a Power Failure. . . . . . . . . . . . . .29
How Time Delays Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Fire Alarm Contact Input Operation . . . . . . . . . . . . . . . . . . . .30
Local and Remote Control Station Operation . . . . . . . . . . . .30
Adjust the Power Transfer Delays . . . . . . . . . . . . . . . . . . . . . .31
Test the System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Local and Remote Key Switch Test . . . . . . . . . . . . . . . . . . . . .32
Fire Alarm Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Manual Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Preventive Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Replacement Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Appendix A Side Mount Hardware Installation . . . . . .35
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
Install the Side Mount Hardware Kit. . . . . . . . . . . . . .35

Introduction 1
Section 1
Introduction
Welcome to the Emergency Lighting Transfer System (ELTS2) Installation and User Operation Manual.
This manual contains the procedures for safe and efficient installation and user operation of the
UL 1008 listed Emergency Lighting Transfer System.
Compliance and Standards
See the ELTS2 datasheet at etcconnect.com for compliance information.
Warnings and Notice Conventions
These symbols are used throughout this document to alert you to danger or important information.
Please email comments about this manual to: [email protected]
Note:
Notes are helpful hints and information that is supplemental to the main text.
CAUTION:
A Caution statement indicates situations where there may be undefined or
unwanted consequences of an action, potential for data loss or an equipment
problem.
WARNING: A Warning statement indicates situations where damage may occur, people
may be harmed, or there are serious or dangerous consequences of an action.
WARNING: RISK OF ELECTRIC SHOCK! This warning statement indicates situations where
there is a risk of electric shock.

2ELTS2 Installation and User Operation Manual
Contacting ETC
If you are having difficulties, and your problem is not addressed by this document, try the ETC
support website at support.etcconnect.com or the main ETC website at etcconnect.com. If
none of these resources are sufficient, contact ETC Technical Services directly at one of the
offices identified below. Emergency service is available from all ETC offices outside of normal
business hours.
When calling for help, please have the following information handy:
• Product model and serial number
• A reference list of other components in your system
ETC, Inc.
Americas
Technical Services Department
3031 Pleasant View Road
Middleton, WI 53562
800-775-4382 (USA, toll-free)
[phone]
[email protected]
ETC GmbH
Germany, Austria, Switzerland, Eastern
Europe, and Russia
Technical Services Department
Ohmstrasse 3
83607 Holzkirchen, Germany
[phone]
[e-mail]
ETC Austin
High End Systems Products
Technical Services Department
2105 Gracy Farms Lane
Austin, TX 78758 USA
800-890-8989 (USA, toll-free)
[phone]
[email protected]
ETC France
France
Zone Urbaparc -
Bâtiment E
6 Boulevard de la Libération
Saint-Denis, 93200
[phone]
[email protected]
ETC Ltd
Europe, Middle East, and Africa
Technical Services Department
26-28 Victoria Industrial Estate
Victoria Road,
London W3 6UU England
[phone]
[email protected]
ETC Asia
Asia
Technical Services Department
Room 1801, 18/F
Tower 1, Phase 1 Enterprise Square
9 Sheung Yuet Road
Kowloon Bay, Kowloon, Hong Kong
[phone]
[email protected]

Introduction 3
Product Overview
The ETC Emergency Lighting Transfer System (ELTS2) is a UL 1008 Listed emergency load transfer
switch designed to switch lighting loads from one power source to another when there is a power
failure or other emergency situation present.
When a normal power failure is detected the ELTS2 automatically transfers the load (both hot and
neutral conductors) of the associated output to a separate emergency power source. When normal
power is restored the ELTS2 reconnects the load to normal power. The local control panel includes a
test key switch and LED indicators that clearly display the system status.
The ELTS2 is available in two panel sizes as standard:
• Small enclosure for two to twelve 20 A circuits of emergency AC lighting loads
• Large enclosure for two to twenty-four 20 A circuits of emergency AC lighting loads
The ELTS2 is available with optional discrete (Type D) emergency branch circuit feeds from an external
circuit breaker panel (by others) or emergency main feed (Type M) with built-in branch circuit
distribution.
Each transfer switch includes a pair of contactors, one for two 20 A circuits of
normal power and one for two 20 A circuits of emergency power. The two
contactors in the assembly are connected by a mechanical interlock in a manner
that ensures the circuits break from normal power before making the transfer
to emergency power and vice versa.
As shown: ELTS2-1-D-277-24
Large NEMA 1 cabinet with 24 Discrete
emergency circuits
As shown: ELTS2-1-M-3P-12
Small NEMA 1 cabinet with Main feed and
12 emergency circuits
(Illustrations shown without internal wiring for clarity.)

4ELTS2 Installation and User Operation Manual
Type D (Discrete Feed) Overview
With Type D ELTS2 units, each 20 A emergency circuit (hot and neutral conductors) are independently
fed from an adjacent emergency branch circuit breaker panel (by others). Normal 20 A circuits are fed
from an adjacent dimmer rack or branch circuit panel. Normal sense power wiring must be run from an
external 10–20 A circuit breaker.
Note:
The sense feed power consumption is essentially none.
ELTS2
TYPE D - DISCRETE FEED
NEMA 1 ENCLOSURE
HOUSELIGHTS
NORMAL EMERGENCY
AUTO
HOUSELIGHTS
NORMAL EMERGENCY
AUTO
HOUSELIGHTS
NORMAL EMERGENCY
AUTO
REMOTE
STATIONS
HOUSELIGHTS
NORMAL EMERGENCY
AUTO
FIRE ALARM
(5) 16 AWG
24 V CLASS 2
(2) 16 AWG
CLASS 2
(DRY CONTACT INPUT)
HOUSELIGHTS
NORMAL EMERGENCY
AUTO
NORMAL SENSE
1 OR 3Ø & N
VIA 10–20 A
CIRCUIT BREAKER
(BY OTHERS)
NORMAL POWER
SOURCE
SENSE FEED
(BY OTHERS)
NORMAL (ONLY) LIGHTING LOADS NORMAL/EMERGENCY LIGHTING LOADS
DIMMER/RELAY OUTPUT TO NORMAL/EMERGENCY LIGHTING LOADS
EMERGENCY POWER
SOURCE
(GENERATOR, INVERTER OR
SECOND UTILITY)
EMERGENCY LIGHTING
CIRCUIT FEEDS
EMERGENCY
BRANCH
CIRCUIT PANEL
(BY OTHERS)
FIRE ALARM
NORMAL MODE EMERGENCY MODE
AUTO
NORMAL
POWER
EMERGENCY
POWER
recent
and
#nav
thru
help
0
Fault-
Fault+
Power
Link
Power
Aux
Error
DMXA
Power
DMXB
Ethernet
1
2
abc
3
def
4
ghi
5
jkl
6
mno
7
pqrs
8
tuv
9
wxyz
DIMMER
RACK
OR
CIRCUIT
BREAKER
PANEL

Introduction 5
Type M (Main Feed) Overview
With Type M ELTS2 units, emergency mains are connected to phase lugs within the unit. Mains power
is distributed through factory wiring to built-in branch circuit distribution and overcurrent protection.
Normal 20 A circuits are fed from an adjacent dimmer rack or branch circuit panel. Normal sense
power wiring must be run from an external 10–20 A circuit breaker.
NORMAL SENSE
1 OR 3Ø & N
VIA 10–20 A
CIRCUIT BREAKER
(BY OTHERS)
NORMAL POWER
SOURCE
EMERGENCY POWER
SOURCE
GENERATOR, INVERTER,
OR SECOND UTILITY
NORMAL (ONLY) LIGHTING LOADS
SENSE FEED
(BY OTHERS)
DIMMER/RELAY OUTPUT TO NORMAL/
EMERGENCY LIGHTING LOADS
NORMAL/EMERGENCY LIGHTING LOADS
HOUSELIGHTS
NORMAL EMERGENCY
AUTO
HOUSELIGHTS
NORMAL EMERGENCY
AUTO
HOUSELIGHTS
NORMAL EMERGENCY
AUTO
REMOTE
STATIONS
HOUSELIGHTS
NORMAL EMERGENCY
AUTO
FIRE ALARM
(5) 16 AWG
24 V CLASS 2
(2) 16 AWG
CLASS 2
(DRY CONTACT INPUT)
HOUSELIGHTS
NORMAL EMERGENCY
AUTO
NORMAL
POWER
AUTO EMERGENCY
POWER
NORMAL MODE
FIRE ALARM
EMERGENCY MODE
! WARNING!
Toreduce the risk of electric
shockor injury to persons,
disconnectall sources of
supplybefore servicing.
ELTS2
TYPE M - MAIN FEED
NEMA 4 ENCLOSURE
recent
and
#nav
thru
help
0
Fault-
Fault+
Power
Link
Power
Aux
Error
DMXA
Power
DMXB
Ethernet
1
2
abc
3
def
4
ghi
5
jkl
6
mno
7
pqrs
8
tuv
9
wxyz
DIMMER
RACK
OR
CIRCUIT
BREAKER
PANEL

6ELTS2 Installation and User Operation Manual
Standard Features
• The ELTS2 has a highly visible integrated local control station with a three-position test key switch
(Auto, Normal Power, and Emergency Power) for system test. The local station also includes a full
complement of system status indicators including:
• The ELTS2 enclosure provides ample space for contractor wiring.
- Standard NEMA 1 rated enclosure is 14 gauge welded steel enclosure with a hinged locking
door.
- Optional NEMA 4 rated enclosure is watertight and includes a hinged locking door.
• 240 and 277 VAC units are provided with integral transformers to step down normal phase A and
emergency phase A feeds to 120 V for the control electronics.
• ELTS2 units are provided with 20 A fuses for branch circuit protection.
• Dual inline pin (DIP) switches on the control electronics are provided for user-selectable timing
delays for power transfer between:
- the loss of normal power and the transfer to emergency power
- the restoration of normal power and the transfer from emergency power back to normal
power
• A normally closed dry contact closure is provided for Fire Alarm input.
• Up to five remote stations may be used per ELTS2 system. Remote stations include a key switch
for switching between normal and emergency states. Each station also includes two LEDs
illuminating the active ELTS2 state: Normal Mode or Emergency Mode.
• After normal power is restored the transfer switches return to the state previous to the power
loss.
• A transfer switch consists of a pair of contactors: One for normal inputs and one for emergency
inputs.
- Each contactor provides connection for line and neutral of two 20 A circuits on the input side.
- The two contactors in the assembly are connected by a mechanical interlock, which ensures
the circuits break from normal power before making the transfer to emergency power.
- Transfer Switches are rated for any mix of loads including tungsten, fluorescent, and discharge
lamps (in general terms, for resistive, capacitive, and inductive loads).
- Transfer Switches are rated for 6,000 cycles at full tungsten load.
F IRE A LARM
N ORMAL M ODE
E MERGENCY M ODE
N ORMAL
P OWER
E MERGENCY
P OWER
A UTO
• Normal Mode: Green LED
• Emergency Mode: Red LED
• Fire Alarm: Red LED

Introduction 7
Product Variants
The ELTS2 is a factory-configured product.
*Custom options with fewer circuits in the large enclosure are also available.
The number of circuits ordered determines the size of enclosure provided. Circuits are available only in
multiples of two.
• Small enclosure: Limited to 2–12 20 A emergency circuits
• Large enclosure: Limited to 14–24 20 A emergency circuits
Definitions
break-before-make: A switch that is configured to break (open) the first set of contacts before
engaging (closing) the new contacts. This prevents the momentary connection of both the normal and
emergency feeds at the same time.
emergency feed: The power feed connected to the ELTS2 that is derived from the emergency source
(generator, inverter, or second utility)
Emergency Mode: The contactors are switched to a state where the load is connected to the
emergency feed.
emergency sense feed: Wires carrying voltage and frequency from Phase A of the emergency source to
the ELTS2 control electronics board for transfer switch operation in Emergency Mode. This connection
is wired for you at the factory.
enclosure: Refers to the ELTS2 cabinet with locking door only.
local station: The key switch station with status indicators on the front of the ELTS2 unit locking door.
normal feed: The power feed connected to the ELTS2 from the normal service.
Normal Mode: The contactors are switched to a state where the load is connected to the normal feed.
normal sense feed: Wires carrying voltage and frequency from the normal source to the ELTS2 control
electronics board for transfer switch operation in Normal Mode. This feed is provided by the installing
electrical contractor.
power fail: When a phase of the normal power feed connected to the ELTS2 falls below the specified
voltage for that phase for the preset amount of time. During a power fail, the ELTS2 will transfer all
connected lighting loads to the alternate power source when it is available and stable.
remote station: A key switch station that is located in a remote location from the ELTS2 unit.
sub panel: The interior panel of the ELTS2 unit including the electronics and transfer switches.
Unit: Refers to the entire ELTS2 including the cabinet with locking door and sub panel.
Enclosure Type Emergency Feed Inputs Voltage Options Circuits
•1=NEMA1
•4=NEMA4
Type D = Discrete Feeds
120 = 120 VAC circuits @ 20 A
• 2–12 for small
enclosure
• 14–24* for
large enclosure
240 = 240 VAC circuits @ 20 A
277 = 277 VAC circuits @ 20 A
Type M = Mains Feed
3P = 208Y/120 VAC (3Ø 4-wire)
1P = 120/240 VAC (1Ø 3-wire)
277 = 277/480 VAC (3Ø 4-wire)
Note:
Do not mix voltages within the ELTS2 unit.

8ELTS2 Installation and User Operation Manual
Section 2
Installation
Installation Requirements
Locate the ELTS2 unit in a location where it will not be subject to tampering or vandalism. If possible,
install the ELTS2 where it is most secure from damage by fire, flood, or other incident likely to require
its use. For proper operation of your ELTS2 unit, be sure the intended installation conforms to the
following environmental and electrical specifications.
Installation Environment
• 0°C–40°C (32°F–104°F ambient temperature) dry room (30–90% humidity, non-condensing)
• Dust-free
• Supported by a wall strong enough to hold the enclosure fully loaded with transfer switches
(large unit approximately 250 lb)
Clearance
• Suggested mounting 36” height to the bottom of the enclosure.
• Clearance on the left and right side of the enclosure should be a minimum of 2”. Emergency main
feed conduit may require extra space due to increased bend radius requirements for larger cables.
• Suggested door clearance is 36” from the front of the small enclosure and 48” from the front of
the large enclosure to allow the enclosure door to open completely.
Enclosure Size Dimensions
(H x W x D) Weight
NEMA 1 Small unit - fully loaded to 12 circuits 36"x24"x8.5" 150 lb
NEMA 1 Large unit - fully loaded to 24 circuits 48"x30"x8.5" 235 lb
NEMA 4 Small unit - fully loaded to 12 circuits 36"x24"x11" 155 lb
NEMA 4 Large unit - fully loaded to 24 circuits 48"x30"x11" 245 lb
48”
36”

Installation 9
Electrical Requirements
The ELTS2 is available in three base voltages including 120 VAC, 240 VAC, or 277 VAC.
120 VAC / 60 Hz units may be any form of 120 VAC power including:
• 208Y / 120 VAC @ 60 Hz, three-phase, 4-wire plus ground
• 120 / 240 VAC @ 60 Hz, single-phase, 3-wire plus ground
• 120 VAC @ 60 Hz, single-phase, 2-wire plus ground
277 VAC / 60 Hz units may be any form of 277 VAC power including:
• 277 / 480 VAC @ 60 Hz, three-phase, 4-wire plus ground
240 VAC / 50 or 60 Hz units may be any form of 240 VAC including:
• 230 / 400 VAC @ 50 Hz, three-phase, 4-wire plus ground
• 240 / 415 VAC @ 50 Hz, three-phase, 4-wire plus ground
Maximum Input Current Ratings
• 480 A for the large unit fully loaded with 24 - 20A emergency circuits
- 160 A per phase in a three-phase configuration
- 240 A per leg when configured for single-phase
• 240 A for the small unit fully loaded with 12 - 20A emergency circuits
- 80 A per phase in a three-phase configuration
- 120 A per leg when configured for single-phase
Branch Circuit Protection
• ELTS2 units utilize built-in 20 A fuses for branch circuit protection.
• Built-in fuses provide 65,000 A Short Circuit Current Rating (SCCR) and ensure compliance with
NEC Section 700.27 Coordination. Larger upstream breakers cannot be tripped by downstream
circuit faults.
• ELTS2 20 A circuits are rated for a maximum continuous load of:
- 1920 watts per circuit at 120 VAC
- 3840 watts per circuit at 240 or 277 VAC
WARNING: Emergency (alternate) power must match normal power within the ELTS2
unit. Mixing voltages within the ELTS2 may cause system failure.
Note:
A unit manufactured as a 120 VAC unit cannot operate on a 240 or 277 VAC supply
and vice versa. 240 and 277 VAC units are manufactured with two transformers that
are used to step down voltage to the control electronics board.
Note:
Please contact ETC Technical Services for assistance with installations involving main
feed types not listed above.
Note:
This equipment should be installed and wired by a qualified electrician. Always follow
applicable building and electrical codes when installing this equipment.
If you are not certain if your installation complies with local or national codes, contact
your local building inspector. Service by qualified personnel only.

10 ELTS2 Installation and User Operation Manual
Sense Feed Requirements
Emergency Sense Feed Requirements
Emergency sense feeds are a requirement for Type D (Discrete Feed) units only. See Type D (Discrete
Feed) Overview
on page 4 for an illustration of a typical installation. Emergency sense feed must
connect to the ELTS2 through an external 10–20 A circuit breaker.
Requirements for emergency sense are limited to only one hot and one neutral conductor from
phase A of the emergency source. Both conductors are pulled to an external single pole 10–20 A circuit
breaker, although only the hot conductor is connected. The conductors are then pulled through
conduit to the ELTS2 unit where they will be connected at the control electronic board (120 VAC units)
or the emergency feed transformer (277 VAC units).
Normal Sense Feed Requirements
Normal sense feed requirements vary depending on the installation.
Example: For a single-phase 120 VAC installation, the normal sense feed requirements include a single-
pole 10 A circuit breaker and a neutral pass-through to the ELTS2.
Note:
The emergency sense circuit breaker may be 10 A, but no more than 20 A.
Normal Power Type Circuit Breaker Note
120 VAC 1Ø 2-wire 10–20 A 1-pole A 10 A circuit breaker is highly
recommended, but up to a
20 A circuit breaker may be
substituted if required.
208 / 120 VAC 3Ø 4-wire 10–20 A 3-pole
240 VAC 1Ø 2-wire 10–20 A 1-pole
240 / 415 VAC 3Ø 4-wire 10–20 A 3-pole
Note:
The normal sense circuit breaker may be 10 A, but no more than 20 A.
E MERGENCY P OWER
S
OURCE
(G ENERATOR , I NVERTER , OR
S
ECOND U TILITY )
P HASE A
H
OT AND N EUTRAL
S
ENSE FEED
( BY OTHERS )
P
HASE A
H
OT AND N EUTRAL
S
ENSE FEED TO THE ELTS2
(BY OTHERS)
CONNECT
VIA
SINGLE POLE
10–20 A CIRCUIT BREAKER
(NEUTRAL PASSES THROUGH TO THE ELTS2)
CONNECT
VIA SINGLE POLE
10–20 A CIRCUIT BREAKER
(BY OTHERS)
(NEUTRAL PASSES THROUGH TO THE ELTS2)
120 VAC 1Ø
NORMAL POWER
SOURCE
SENSE FEED
(BY OTHERS)
SENSE FEED TO THE ELTS2
(BY OTHERS)

Installation 11
Transfer Switch Specification
A transfer switch includes a pair of contactors: one for normal inputs and one for emergency inputs
(factory wired). Transfer switches provide connection for line and neutral of two 20 A circuits on the
input side. The two contactors in the assembly are connected by a mechanical interlock in a manner
that ensures the circuits break from normal power before making the transfer to emergency power,
and vice versa
.
The transfer switches are rated for mixed loads consisting of resistive, tungsten, and discharge lamps.
Prepare for Installation
Verify Contents of the Shipping Carton
Before you begin installation check your shipment for physical damage that may have occurred during
transit.
• If you discover damage be sure to document it to help with the claim to your shipper.
• Unpack your order and check the contents against the packing list to be sure your order is
complete.
• Open the ELTS2 enclosure door and check for loose connections or broken components caused
by shipping vibration.
• If you discover a problem, contact ETC (see
Contacting ETC on page 2 ).
Parts and Specialty Tools Required
• Required mounting hardware (not supplied by ETC):
- 4 each 3/8” bolts or screws 2"–4” long
- Wall anchors are suggested
• Required 10–20 A external circuit breaker (not supplied by ETC) for normal sensing wires. This
breaker may be 1-pole, 2-pole, or 3-pole depending on the power source.
Cable Specification and Conduit Access
Note:
All Class 2 low voltage wiring is required to enter the unit in the top-left conduit entry
access point. Do not run the Class 2 wires in the same conduit as sense, phase, or
load power wiring.
• Emergency inputs to the transfer switch are
factory-wired, leaving only the normal inputs
to the switch for customer termination.
• Load outputs from the transfer switch are
factory-wired to the over-current protection
fuses located at the bottom of the ELTS2, and
then to the emergency load output terminal
block for customer termination.
Land normal
loads here

12 ELTS2 Installation and User Operation Manual
Type D (Discrete Feed) Cable Specification and Conduit Access
Connection Purpose Terminal
Accepts Torque Notes
20 A circuit from a normal source
(dimmer rack or circuit breaker
panel) to the transfer switch
12–8 AWG 10 in/lb Line and neutral conductors only! No
ground lugs provided in the ELTS2.
20 A discrete emergency branch
circuit breaker feed input 12–8 AWG Line and neutral conductors only! No
ground lugs provided in the ELTS2.
Emergency lighting load output
terminal strip 22–8 AWG
1 normal sense feed:
Single-phase or three-phase
(must match normal power feeds)
+ neutral
20–6 AWG
Normal power sense must connect to
the ELTS2 through an external 10 A
circuit breaker. See
Sense Feed
Requirements on page 10 .
Emergency sense feed (single-
phase + neutral) 20–6 AWG
12 in/lb for
120 V;
8 in/lb for
240/277 V
Emergency power sense must connect
to the ELTS2 through an external
10–20 A circuit breaker. See
Sense Feed
Requirements on page 10 .
Fire Alarm: Dry contact input 22–10 AWG
2 conductor Class 2 Normally closed dry contact input
Remote Stations
Belden 9620
recommended or
five runs of 12–22
AWG
Up to 5 remote stations per system
typically wired in a parallel topology.
Connections are +24 VDC Class 2.
Required conduit entry:
Normal sense feed, remote
station data termination, and
fire alarm contact input
EM1 L
EM1 N
EM2 L
EM2 N
EM3 L
EM3 N
EM4 L
EM4 N
EM5 L
EM5 N
EM6 L
EM6 N
EM7 L
EM7 N
EM8 L
EM8 N
EM9 L
EM9 N
EM10 L
EM10 N
EM11 L
EM11 N
EM12 L
EM12 N
EM13 L
EM13 N
EM14 L
EM14 N
EM15 L
EM15 N
EM16 L
EM16 N
EM17 L
EM17 N
EM18 L
EM18 N
EM19 L
EM19 N
EM20 L
EM20 N
EM21 L
EM21 N
EM22 L
EM22 N
EM23 L
EM23 N
EM24 L
EM24 N
Conduit entry:
Normal load input from
dimmer rack or branch
circuit breaker panel
Conduit entry:
Load output from ELTS2 to
emergency lighting loads
Conduit entry:
Normal load input from
dimmer rack or branch
circuit breaker panel
Conduit entry:
Discrete emergency branch
circuit breaker feed input
Transformers on 240 and
277 VAC units only

Installation 13
Type M (Main Feed) Cable Specification and Conduit Access
Purpose Terminal Accepts Torque Notes
20 A circuit from a normal source
(dimmer rack or circuit breaker
panel) to the transfer switch
14–8 AWG 10 in/lb
Line and neutral conductors only!
No ground lugs provided in the
ELTS2.
1 normal sense feed: Single-
phase or three-phase
NOTE: Must match normal power
feeds + neutral
6–20 AWG
Normal power sense must connect
to the ELTS2 through an external
10–20 A circuit breaker. See
Sense
Feed Requirements
on page 10 .
Emergency Main Feed (small
enclosure 2–12 circuits)
Ø, Gnd, and N lugs
2/0–14 AWG 10 ft-lb Use with an emergency power
source (generator, inverter, or
second utility).
NOTE: Emergency and normal
power must match within the unit.
Emergency Main Feed (large
enclosure 2–24 circuits)
Ø and N lugs
350MCM–6 AWG
Ground lug
2/0–14 AWG
31.25 ft-lb
10 ft-lb
Emergency lighting load output
terminal strip 22–8 AWG
Fire Alarm: Dry contact input 10–22 AWG,
2 conductor Class 2 Normally closed dry contact input
Remote Stations
Belden 9620
recommended or five
runs of 12–22 AWG
Up to 5 remote stations per system
typically wired in a parallel
topology. Connections are
+24 VDC Class 2.
Required conduit entry:
Normal sense feed input,
remote station data termination,
and fire alarm contact input
Conduit entry:
Emergency mains feed only
Transformers on 240
and 277 VAC units only
Conduit entry:
Normal load input from
dimmer rack or branch circuit
breaker panel
Conduit entry:
Load output from ELTS2 to
emergency lighting loads
Conduit entry:
Normal load input from
dimmer rack or branch
circuit breaker panel
Earth ground

14 ELTS2 Installation and User Operation Manual
Install the ELTS2
Determine the Installation Location
Install the ELTS2 in a location where it will not be subject to tampering or vandalism. If possible, install
the ELTS2 where it is secure from damage by fire, flood, or other incident likely to require its use.
The ELTS2 unit should be supported by a wall strong enough to hold the enclosure fully loaded with
transfer switches. See
Clearance on page 8 for product weight, dimensions, and clearance
requirements.
After determining the installation location for your ELTS2 unit, follow the instructions below.
Install Mounting Hardware
Installation of the mounting hardware depends on the type of enclosure you are installing: the
standard NEMA 1 or the optional NEMA 4 enclosure.
WARNING: ELTS2 units are heavy. Be sure you have proper equipment or assistance to
lift the unit into place and support it while securing the mounting
hardware.
AVERTISSEMENT : Les armoires ELTS2 sont lourdes. Assurez-vous de disposer de
l'équipement ou de l'assistance appropriés pour soulever l'armoire et la
soutenir fermement lors de son montage.
Large 28.5”
Small 22.5”
Large 49.56”
Small 37.56”
Large 27.25”
Small 21.25”
Large 31.25”
Small 25.25”
Large 49.6”
Small 37.6”
Large 46.5”
Small 34.5”
NORMAL
POWER
AUTO EMERGENCY
POWER
NORMAL MODE
FIRE ALARM
EMERGENCY MODE
! WARNING!
Toreduce the risk of electric
shockor injury to persons,
disconnectall sources of
supplybefore servicing.
NEMA 4 enclosureNEMA 1 enclosure
NORMAL
POWER
AUTO EMERGENCY
POWER
NORMAL MODE
FIRE ALARM
EMERGENCY MODE
! WARNING!
Toreduce the risk of electric
shockor injury to persons,
disconnectall sources of
supplybefore servicing.

Installation 15
The NEMA 1 and NEMA 4 enclosures may be installed utilizing the standard top/bottom mounting tabs
that are provided with the unit. As an alternative to the standard top/bottom tab mounting, you may
install the NEMA 1 enclosure using the (optional) horizontal tab mounting kit for side mounting. See
Side Mount Hardware Installation on page 35 .
Install NEMA 1 Enclosure
Note:
The installation contractor must follow all local code restrictions.
WARNING: ELTS2 units are heavy. Be sure you have proper equipment or assistance to
lift the unit into place and support it while securing the mounting
hardware.
AVERTISSEMENT : Les armoires ELTS2 sont lourdes. Assurez-vous de disposer de
l'équipement ou de l'assistance appropriés pour soulever l'armoire et la
soutenir fermement lors de son montage.
Large 27.25”
Small 21.25”
Large 31.25”
Small 25.25”
Large 49.6”
Small 37.6”
Large 46.5”
Small 34.5”
NEMA 1 enclosure
N ORMAL
P OWER
A UTO
E MERGENCY
P OWER
N ORMAL M ODE
F IRE A LARM
E MERGENCY M ODE
! W ARNING !
Toreduce the risk of electric
shockor injury to persons,
disconnectall sources of
supplybefore servicing.
1: Using the measurements provided, pre-drill and install two
3/8” mounting bolts for the lower two support keyhole slots.
2: Using the measurements provided, pre-drill the holes for the
top two 3/8” mounting bolts.
3: Place the enclosure on the wall, resting on the lower two
mounting bolts installed in step 1.
4: Secure the enclosure to the wall with the top two mounting
bolts. Make sure all four mounting bolts are properly tightened
to the applicable torque recommended for the selected
fastener.
5: Check that the enclosure is plumb and secure to the wall.
Strictly follow all local code restrictions.

16 ELTS2 Installation and User Operation Manual
Install NEMA 4 Enclosure
Rough-In Conduit and Cable
Requirements for installation vary depending on the type of ELTS2 in your installation (either Type D -
Discrete Feed or Type M - Main Feed). See
page 12 and page 13 for specification of cable and conduit
access requirements for each ELTS2 type.
Note:
Use watertight conduit hubs or equivalent provisions for watertight connection at the
conduit entrance to maintain the integrity of the NEMA 4 enclosure.
WARNING: ELTS2 units are heavy. Be sure you have proper equipment or assistance to
lift the unit into place and support it while securing the mounting
hardware.
AVERTISSEMENT : Les armoires ELTS2 sont lourdes. Assurez-vous de disposer de
l'équipement ou de l'assistance appropriés pour soulever l'armoire et la
soutenir fermement lors de son montage.
WARNING: RISK OF DEATH BY ELECTRIC SHOCK! To prevent death or serious injury
due to electrical shock, normal (utility) and emergency (alternate) power
supplies must be turned off prior to connecting power source and load
lines to the ELTS2 unit.
Follow appropriate Lockout/Tagout procedures as mandated by NFPA 70E.
Any work must comply with OSHA Safe Working Practices.
AVERTISSEMENT : RISQUE DE MORT PAR ÉLECTROCUTION! Pour éviter des blessures graves
ou mortelles dues à un choc électrique, coupez l'alimentation normale
(secteur) et d'urgence (alternative) avant de connecter la source
d'alimentation et les lignes de charge à l'armoire ELTS2.
Suivez les procédures de Consignation/Déconsignation appropriées
prescrites par la norme NFPA 70E.
Large 28.5”
Small 22.5”
Large 49.56”
Small 37.56”
NORMAL
POWER
AUTO EMERGENCY
POWER
NORMALMODE
FIREALARM
EMERGENCYMODE
! WARNING!
Toreduce the risk of electric
shockor injury to persons,
disconnectall sources of
supplybefore servicing.
NEMA 4 enclosure
1: Using the measurements provided, pre-drill the holes for the
bottom two 3/8” mounting bolts.
2: Lift the enclosure on the wall with the mounting holes aligned
with your prepared mounting holes, and install the two 3/8”
mounting bolts for the upper mounting support tabs.
3: Install the two 3/8” mounting bolts for the lower two mounting
support tabs.
4: Check that the enclosure is plumb and secure to the wall.
Strictly follow all local code restrictions.