Magnum Dimensions CSW2012-X User manual

Owner’s Manual
CSW2012-X
Pure Sine Wave Inverter

© 2015 Sensata Technologies i
Thank you from all of us at Sensata Technologies for purchasing this
CSW2012-X inverter. The CSW2012-X is under the Magnum-Dimensions brand
from Sensata Technologies. We understand that you have many purchasing
options in the marketplace and are pleased that you have decided on this
product.
At Sensata, we are committed to providing you with quality products and
services, and hope that your experience with us is pleasant and professional.
Disclaimer of Liability
Since the use of this manual and the conditions or methods of installation,
operation, use and maintenance of the CSW2012-X inverter is beyond the
control of Sensata Technologies, this company does not assume responsibility
and expressly disclaims liability for loss, damage or expense, whether direct,
indirect, consequential or incidental, arising out of or in any way connected
with such installation, operation, use, or maintenance.
Note as well that while every precaution has been taken to ensure the
accuracy of the contents of this manual, the specifications and product
functionality may change without notice. Sensata assumes no responsibility
for errors or omissions.
Restrictions on Use
The CSW2012-X inverter may only be used in life-support devices or systems
with the express written approval of Sensata Technologies. Failure of the
CSW2012-X inverter can reasonably be expected to cause the failure of that
life-support device or system, or to affect the safety or effectiveness of that
device or system. If the CSW2012-X inverter fails, it is reasonable to assume
that the health of the user or other persons may be endangered.
Copyright Notice
Copyright © 2015 by Sensata Technologies. All rights reserved. Permission to
copy, distribute, and/or modify this document is prohibited without express
written permission from Sensata.
Document Information
Description – CSW2012-X Owner’s Manual
Part Number and Revision – 64-0074 Rev B
Date Published – July 2015
This manual is printed without color for cost savings. However, this entire
manual is available with many of the figures in color and can be downloaded at
www.magnum-dimensions.com.
Contact Information
For Magnum-Dimensions products:
Sensata Technologies Phone: [phone]
2211 West Casino Rd. Fax: [phone]
Everett, WA 98204 Web: www.magnum-dimensions.com
Record the unit’s model and serial number in case you need to provide
this information in the future. It is much easier to record this information
now, instead of trying to gather it after the unit has been installed.
Model: Serial Number:
CSW2012-X BF

ii © 2015 Sensata Technologies
IMPORTANT PRODUCT SAFETY INSTRUCTIONS
This manual contains safety instructions that must be followed during the
installation and operation of this product. Read all instructions and safety
information on the inverter and in this manual before installing or using.
Safety Symbols
To reduce the risk of electrical shock, fire, or other safety hazard, the
following safety symbols have been placed throughout this manual to
indicate dangerous situations and important safety instructions.
WARNING: Indicates that failure to take a specified action could
result in physical harm to the user.
CAUTION: Indicates that failure to take a specified action could result
in damage to the equipment.
Info: Indicates information that emphasizes or supplements important
points of the main text.
Product Safety Warnings
WARNINGS: Failure to follow the instructions below and in this
manual can result in death or serious injury.
• All electrical work must be performed in accordance with local, state and
federal electric codes.
• This product is designed for indoor/compartment installation. Do not
expose to rain, snow, moisture, or liquids of any type.
• Use insulated tools to reduce the chance of electrical shock or accidental
short circuits. Be sure to remove all jewelry such as rings, watches,
bracelets, etc., when installing or performing maintenance on the inverter.
• Always disconnect the batteries or energy source prior to installing or
performing maintenance on the inverter. Live power may be present at
more than one point since an inverter utilizes both batteries and AC.
• Do not cover or obstruct any air vent openings and/or install in a zero-
clearance compartment - always operate unit in an open area.
• When working with electrical equipment or lead acid batteries, have
someone nearby in case of an emergency.
• Study and follow all the battery manufacturer’s specific precautions when
installing, using, and servicing the battery connected to the inverter.
• While working with batteries, wear eye protection and gloves, and avoid
touching your eyes. Keep fresh water and soap on hand in the event battery
acid comes in contact with eyes. If this occurs, cleanse right away with soap
and water for a minimum of 15 minutes and seek medical attention.
• Batteries produce explosive gases, DO NOT smoke or have an open spark
or fire near the system.
• Avoid dropping any metal tool or object on the battery. Doing so could
create a spark or short circuit which goes through the battery or another
electrical tool and may cause an explosion.
• Shock Hazard! Keep away from children!
• These inverters provide household AC, treat the AC output sockets the
same as regular wall AC sockets at home.
• Explosion hazard! DO NOT use this inverter in the vicinity of flammable
fumes or gases (such as propane tanks or large engines).
• These inverters contain no user-serviceable parts. See the Warranty
section for how to handle service issues.

© 2015 Sensata Technologies iii
Table of Contents
1.0 Introduction............................................................................. 1
1.1 Features ................................................................................. 1
1.2 How this Inverter Works............................................................ 4
1.3 Advantages of a Pure Sine Wave Inverter .................................... 4
2.0 Installation .............................................................................. 5
2.1 Pre-Installation ........................................................................ 5
2.1.1 Installation Guidelines ........................................................ 5
2.1.2 Unpacking and Inspection ................................................... 5
2.1.3 Tools Required ................................................................... 5
2.2 Locating and Mounting the Inverter ............................................ 7
2.3 Wiring the Inverter – General Requirements ................................ 9
2.3.1 Wiring Requirements .......................................................... 9
2.3.2 Torque Requirements.......................................................... 9
2.4 DC Wiring ............................................................................. 10
2.4.1 DC Wire Sizing................................................................. 11
2.4.2 DC Overcurrent Protection................................................. 12
2.4.3 DC Grounding.................................................................. 12
2.4.4 DC Cable Connections....................................................... 12
2.4.5 Wiring the Battery Bank.................................................... 13
2.4.6 Appliances and Run Time .................................................. 13
2.4.7 Wiring the Inverter to the Battery Bank............................... 14
2.5 AC Wiring.............................................................................. 16
2.5.1 Pre-AC Wiring Requirements.............................................. 16
2.5.2 AC Wire Size and Overcurrent Protection............................. 16
2.5.3 AC Neutral to Safety Ground Bonding ................................. 17
2.5.4 AC Terminal Block Connections .......................................... 18
2.5.5 AC Conductor Wiring Steps................................................ 18
2.5.6 Removing the Display Panel............................................... 22
2.6 Testing the Inverter ................................................................ 23
2.6.1 Inverter Functional Test .................................................... 23
3.0 Operation............................................................................... 24
3.1 Inverter Mode........................................................................ 24
3.2 By-Pass Mode ........................................................................ 24
3.3 Display Panel Operation .......................................................... 25
3.4 Understanding Loads .............................................................. 28
4.0 Troubleshooting..................................................................... 29
5.0 Specifications......................................................................... 35
Appendix A - Battery Information ................................................ 36
Battery Bank Sizing ...................................................................... 36
Battery Types............................................................................... 36
Battery Configuration.................................................................... 36
Series Wiring ............................................................................ 36
Parallel Wiring........................................................................... 37
Series-Parallel Wiring ................................................................. 37
Appendix B - Preventive/Periodic Maintenance............................ 38
Recommended Inverter and Battery Care ........................................ 38
RV/Marine Off-Season Storage ....................................................... 38
Appendix C - Regulatory and FCC Information.............................. 39
Appendix D - Limited Warranty .................................................... 40
How to Receive Warranty Service.................................................... 40

iv © 2015 Sensata Technologies
List of Figures
Figure 1-1, Front Panel Features.......................................................... 1
Figure 1-2, Front Panel Features (Cover Removed)................................. 2
Figure 1-3, Back Panel Features .......................................................... 3
Figure 1-4, AC Waveforms .................................................................. 4
Figure 2-1, Basic System Diagram ....................................................... 6
Figure 2-2, Approved Mounting Positions .............................................. 8
Figure 2-3, CSW2012-X Dimensions..................................................... 8
Figure 2-4, DC Cable to Battery Terminals........................................... 15
Figure 2-5, DC Cable to Inverter’s DC Terminals .................................. 15
Figure 2-6, AC Wiring (20A By-Pass and GFCI output)) ......................... 20
Figure 2-7, AC Wiring (30A By-Pass) .................................................. 21
Figure 2-8, Remote Cable ................................................................. 22
Figure 3-1, Display Panel .................................................................. 25
Figure 3-2, Inverter Setting Flow Chart .............................................. 26
Figure A-1, Series Battery Wiring....................................................... 36
Figure A-2, Parallel Battery Wiring ..................................................... 37
Figure A-3, Series-Parallel Battery Wiring............................................ 37
Tables
Table 2-1, Torque Requirements .......................................................... 9
Table 2-2, DC Wire/Overcurrent Device for Rated Use........................... 11
Table 2-3, Appliance Power Consumption and Run Time ........................ 13
Table 3-1, Display Functions/Statuses ................................................ 25
Table 3-2, Inverter Settings .............................................................. 27
Table 4-1, Inverter Error Codes ......................................................... 29
Table 4-2, Troubleshooting ................................................................ 30
Table 5-1, CSW2012-X Specifications ................................................. 35

© 2015 Sensata Technologies 1
1.0 Introduction
1.0 Introduction
Congratulations on your purchase of the CSW2012-X inverter. The CSW2012-X
is a “pure” sine wave inverter with an internal transfer switch and is sold
under the Magnum-Dimensions brand from Sensata Technologies. This unit
is designed to be powerful, yet simple to operate, and will provide you with
reliable AC power for trouble-free use. Please read this chapter to familiarize
yourself with the features and benefits of your CSW2012-X inverter.
1
2
3
4
5
6
Figure 1-1, Front Panel Features
1.1 Features
The front panel of the CSW2012-X inverter is equipped with the following
features (see Figure 1-1):
1. AC Wiring Access Cover – when this cover is removed, it provides
access to the AC wiring terminals used to hardwire all inverter AC input
and output wiring (see Figure 1-2). Remove four screws to remove the
access cover.
2. GFCI – a 20-amp, Ground Fault Circuit Interrupter (GFCI) protected, AC
outlet. This GFCI outlet quickly stops the flow of electricity in the event
a ground fault occurs on the device that is plugged into the inverter.
3. USB Port – allows USB-enabled devices to be powered and charged
(provides 5 VDC/750 mA).
4. Serial Number – the unique identification number assigned to each
unit (with a model-specific prefix). Note: Enter your inverter’s serial
number in the table at the bottom of page i. It is to easier to record this
information now, instead of trying to gather it after the unit has been
installed.
5. Display Panel – a removable/remote display that shows the inverter’s
measured battery voltage, total AC output power, and any error or
warning codes. This display has LEDs that provide the inverter’s status,
and also includes the SELECT and POWER button switches used to set
up and turn the inverter on and off (See Section 3.3).
6. AC Output Circuit Breaker – this supplementary 20-amp circuit
breaker protects the unit’s GFCI outlet and is also connected in circuit
with the AC 2 output (L2 and N2 outputs). The circuit breaker pops out
when it opens—press in to reset.

2 © 2015 Sensata Technologies
1.0 Introduction
Figure 1-2, Front Panel Features (Cover Removed)
10
9
8
7
The following front panel features are available on the CSW2012-X inverter
when the access cover is removed (See Figure 1-2):
Info: To access and view the AC terminal block and ground termi-
nal, remove the four Phillips screws holding the AC wiring access
cover.
7. AC Entry/Exit Openings – two 1/2” knockouts are provided to
accommodate the inverter’s AC input and output wiring.
8. AC Ground Connection – used to connect all AC input and output
grounds. To attach multiple ground wires (i.e., ground wires from the AC
input and output circuits), use a pressure or mechanical connector (i.e.,
ring terminal).
9. AC Input Terminal – a two-pole terminal block used to connect the
inverter’s AC input wiring. This terminal block allows a service/distribution
panel (main panel) to be wired to the inverter’s input.
10. AC Output Terminal – this four-pole terminal block is used to connect
the inverter’s AC output wiring. This terminal block allows a dedicated
panel (sub-panel) to be connected between the inverter’s output wiring
and the AC loads.
The AC 1 output terminals (L1/N1) allow a pass-thru (By-Pass mode)
current of 30 amps. The AC 2 output terminals (L2/N2) are protected by the
inverter’s 20-amp circuit breaker (Figure 1-1, Item 6) which limits the pass-
thru current of 20 amps.
CAUTION: The inverter’s internal AC transfer relay is rated for
30 amps. The pass-thru current from the input terminal to the AC
1 (L1/N1) output terminals must be no greater than 30 amps or
damage to the internal relay may occur.
Info: The AC input and output terminals can accept one #14 to
#10 AWG (2.1 to 5.3 mm2) CU stranded wire. They use slotted head
screws and have a recommended maximum tightening torque of 5
to 8 lbf-in (0.6 to 0.9 N-m).

© 2015 Sensata Technologies 3
1.0 Introduction
The back panel of the CSW2012-X inverter is equipped with the following
features (See Figure 1-3):
11. Model Number – the model number of the inverter and other
information.
12. Cooling Fan(s) – intake cooling fans that automatically turn on when
the inverter’s internal temperature rises above 122°F (50°C). The fan
turns off when the inverter’s internal temperature falls below 122°F
(50°C).
13. Mounting Flanges (front and rear) – used to mount and secure the
inverter to a shelf/wall.
14. DC Positive Terminal (red) – the inverter’s connection to the positive
terminal on the 12 VDC battery bank.
15. DC Negative Terminal (black) – the inverter’s connection to the
negative terminal on the 12 VDC battery bank.
16. DC Ground Connection – the connection that is used to tie the
exposed chassis of the inverter to the DC grounding system. The DC
grounding system could be the vehicle’s chassis, the DC grounding bus,
or the engine’s negative bus. To attach ground wires, use a pressure or
mechanical connector (i.e., ring terminal) with a 1/4” opening.
Figure 1-3, Back Panel Features
11
13
12
16
14
15

4 © 2015 Sensata Technologies
1.0 Introduction
1.2 How this Inverter Works
There are two modes of operation associated with the CSW2012-X inverter:
• Inverter Mode:
When the inverter is properly connected to batteries and turned on, the
direct current (DC) from the batteries is transformed into a pure sine wave
alternating current (AC). This AC is similar to the voltage provided by
your utility and is used to power any electrical appliances (i.e., AC loads)
connected to the inverter’s output.
• By-Pass (pass-through) Mode:
When an external source of AC power (i.e., utility power or generator) is
connected and qualified on the inverter’s AC input, it operates in By-pass
mode. In By-pass mode, the unit automatically closes an internal AC transfer
relay that passes the incoming AC power directly to the inverter’s output to
continue powering the connected electrical appliances.
1.3 Advantages of a Pure Sine Wave Inverter
Today’s inverters come in three basic output waveforms: square wave,
modified sine wave (which is actually a modified square wave) and pure sine
wave (see Figure 1-4).
Modified sine wave inverters approximate a pure sine wave form and will run
most appliances and electronics without any problems. These inverters are
less expensive, and therefore, offer a viable alternative to more expensive
pure sine inverters.
The output of the CSW2012-X inverter—which is pure sine wave—is equal to,
or in many cases, better than the utility power used in your home. Virtually
any electronic device will operate from a pure sine wave inverter. Motors
run cooler, microwaves usually cook faster, and clocks keep better time just
to name a few examples. Without compromising quality or performance,
the CSW2012-X provides you with all the advantages of a pure sine wave
inverter at a much lower cost than many on the market.
Figure 1-4, AC Waveforms
TIME
VOLTAGE
40
80
0
120
40
160
200
80
120
160
200
Modified
Sine Wave
Sine Wave
Square Wave

© 2015 Sensata Technologies 5
2.0 Installation
2.0 Installation
Review this section and all safety instructions before proceeding with the
installation of your inverter.
WARNING: Installations should be performed by qualified
personnel, such as a licensed or certified electrician. The installer
determines which safety codes apply and ensures all applicable
installation requirements are followed. Applicable installation codes
vary depending on the specific location and application.
WARNING: Before installing, review the “Important Product Safety
Information” on page ii and adhere to all cautionary markings located
on the inverter and on the batteries.
2.1 Pre-Installation
Before proceeding, read the entire Installation section to determine how
best to install your CSW2012-X inverter. The more thorough you plan in the
beginning, the better your inverter needs will be met. There is a simplified
system diagram shown in Figure 2-1. This diagram should be reviewed to
assist you in planning and designing your installation. This drawing is not
intended to override or to restrict any national or local electrical codes,
and should not be the determining factor as to whether the installation is
compliant, that is the responsibility of the electrician and the onsite inspector.
2.1.1 Installation Guidelines
• Before connecting any wires, determine the cable routes throughout the
vehicle or boat, both to and from the inverter.
• Always check for existing electrical, plumbing, or other areas of potential
damage BEFORE drilling or cutting into walls.
• Make sure all wires have a smooth bend radius and do not become kinked.
• If installing this inverter in a boat, RV or truck, ensure the conductors
passing through walls, bulkheads, or other structural members are
protected. This minimizes insulation damage (such as chafing), which
can be caused by vibration or constant rubbing.
2.1.2 Unpacking and Inspection
Carefully remove the inverter from its shipping container and inspect all
contents. Verify the following items are included:
• CSW2012-X inverter
• CSW2012-X Owner’s Manual
If items appear to be missing or damaged, contact your authorized Magnum-
Dimensions dealer or Magnum-Dimensions directly.
*** Save your proof-of-purchase as a record of your ownership; it
is needed if the unit should require in-warranty service. ***
2.1.3 Tools Required
Installing the inverter is simple and requires the following:
• Adjustable wrench (10-13 mm) • Level • Drill
• #10 Mounting screws (x4) • Pencil • Drill bits
• Phillips screwdriver

6 © 2015 Sensata Technologies
2.0 Installation
Figure 2-1, Basic System Diagram
AC OUT*
AC Main Panel
(Branch Circuit Breaker to
Inverter: 30A max)
AC IN
AC Loads
(L1/N1 = 30A max,
L2/N2 = 20A max)
AC
Sub-Panel
AC
Outlet
DC
Ground
(Vehicle
chassis, DC
ground bus,
or engine
negative bus)
CSW2012-X Inverter
AC Source
(120VAC, 60 Hz Sinewave)
DC
Disconnect
Fuse
Battery
Bank
Tools
TV DVD
* Maximum pass-thru current from AC output terminals:
L1/N1 output terminals = 30 amps,
L2/N2 output terminals = 20 amps (in series with GFCI outlet).

© 2015 Sensata Technologies 7
2.0 Installation
2.2 Locating and Mounting the Inverter
WARNINGS:
• Do not mount the inverter near any flammable or combustible
fluid or components.
• Provide adequate clearance/ventilation to the inverter. Do not
cover or obstruct any air vent openings and/or install in a zero-
clearance compartment.
The CSW2012-X inverter should only be installed and mounted in a location
that meets the following requirements:
Clean and dry – The inverter should not be installed in an area that allows
dust, fumes, insects, or rodents to enter or block the inverter’s ventilation
openings. This area also must be free from any risk of condensation, water,
or any other liquid that can enter or fall on the inverter. Inverter failure under
these conditions is not covered under warranty.
Cool – The inverter should be protected from direct exposure to the sun or
to any equipment that produces extreme heat. The ambient temperature
should be between 32°F (0°C) and 104°F (40°C); note that the inverter’s
output specifications are rated at 77°F (25°C), so the cooler the better.
Ventilated – In order for the inverter to provide full output power and
avoid over-temperature fault conditions, do not cover or block the inverter’s
ventilation openings, or install this inverter in an area with limited airflow.
Allow a minimum airspace clearance of 3” (7.6 cm) around the unit to provide
optimum ventilation.
Safe – Keep any flammable/combustible material (e.g., paper, cloth, plastic,
etc.,) that may be ignited by heat, sparks, or flames at a minimum distance
of 2 feet (60 cm) away from the inverter. Do not install in any area that
contains extremely flammable liquids like gasoline or propane, or in locations
that require ignition-protected devices.
Close to the battery bank – As with any inverter, it should be located as
close to the batteries as possible. Long DC wires tend to lose efficiency and
reduce the overall performance of an inverter. However, the unit should not
be installed in the same compartment as the batteries or mounted where it
will be exposed to gases produced by the batteries. These gases are corrosive
and will damage the inverter; also, if these gases are not ventilated and if
allowed to collect, they could ignite and cause an explosion.
Accessible – Do not block access to the front or back of the inverter. Allow
room to view any indicators or the digital display and to access the AC and
DC wiring connections—these wiring connections will need to be checked and
tightened periodically.
Orientating the inverter - When mounted indoors, the CSW2012-X inverter
can be mounted on/underneath a horizontal surface (shelf or table) or on a
vertical surface (wall or bulkhead) with the DC terminals facing left, right, or
up; do not mount with the DC terminals facing downward (see Figure 2-2).
After determining your mounting position, use the base of the inverter’s
chassis as a template to mark your mounting screw locations (or, refer to the
dimensions in Figure 2-3). Remove the inverter and drill pilot holes into the
mounting surface. Secure the inverter to the surface using the appropriate
corrosion-resistant hardware. If this unit is used in a mobile application, you
may want to place flexible washers or bushings between the mounting surface
and the inverter’s mounting flanges to reduce vibration.

8 © 2015 Sensata Technologies
2.0 Installation
Figure 2-2, Approved Mounting Positions
Flat on a
horizontal surface
(right side up
or upside down).
DC terminals to the
right, left or top.
Note: CSW2012-X cannot
be mounted with DC
terminals facing down.
Figure 2-3, CSW2012-X Dimensions
8
1/2
" (21.6 cm)
Top
12.5’’ (31.8 cm)
8.6’’ (21.8 cm)
9.1’’ (23 cm)
17.1’’ (43.5 cm)
Front (AC Side) Back (DC Side)
4.5’’
(11.5 cm)

© 2015 Sensata Technologies 9
2.0 Installation
2.3 Wiring the Inverter – General Requirements
This section describes the requirements and recommendations for wiring the
CSW2012-X inverter. Before wiring the inverter, carefully read all instructions.
The NEC (National Electric Code, ANSI/NFPA 70) for the United States and
the CEC (Canadian Electrical Code) for Canada provide the standards for
safely wiring residential and commercial installations. The NEC/CEC lists the
standards for wire sizes, overcurrent protection, and installation methods
and requirements.
Inverter/charger systems involve power from multiple sources (inverter,
generator, utility, batteries, solar arrays, etc.) which can make the wiring
more hazardous and challenging.
WARNING: Ensure all sources of DC power (i.e., batteries, solar,
wind, or hydro) and AC power (utility power or AC generator) are
de-energized (i.e., breakers opened, fuses removed) before pro-
ceeding—to prevent accidental shock.
WARNING: Wiring should meet all local codes/standards and be
performed by qualified personnel (i.e., licensed electrician).
2.3.1 Wiring Requirements
• All conductors that are at risk for physical damage must be protected
by tape or placed in a raceway.
• Always check for existing electrical, plumbing, or other areas of
potential damage prior to making cuts in structural surfaces or walls.
• Use only copper wires with a minimum temperature rating of 75° C
(194° F).
• Do not mix AC and DC wiring in the same conduit or panel unless
specifically approved/designed for both AC and DC wiring. Where
DC wiring must cross AC or vice-versa, try to make the wires at the
crossing point perpendicular (90 degrees) to one another.
• Both AC and DC overcurrent protection must be provided as part of
the installation.
• The inverter requires a reliable negative and ground return path
directly to the battery.
2.3.2 Torque Requirements
All wiring to the AC and DC terminals should be checked periodically (once a
month) for proper tightness. For the torque requirements, refer to Table 2-1.
If you don’t have a torque wrench, ensure all connections are tight.
Table 2-1, Torque Requirements
Terminal Size Torque
Requirements Tool Size Needed
AC Terminals
(AC input/output)
M3.5 × 7
screws
5 - 8 lbf-in
(.6 to .9 N-m)
flat-head screwdriver
(2.9 to 3.5 mm blade)
DC Terminals M8 x 1.25
Hex nuts 16 to 21 lbf-ft
(21.7 to 28.5 N-m) 13 mm wrench
DC Ground M6 x 1.0
Hex nut 79 to 96 lbf-in
(8.9 to 10.9 N-m) 10 mm wrench

10 © 2015 Sensata Technologies
2.0 Installation
2.4 DC Wiring
This section describes the inverter’s required DC wire sizes, the recommended
disconnect/overcurrent protection, and how to make the DC connections to
the inverter and the battery bank.
WARNING: Even though DC voltage can be regarded as “low
voltage”, significant hazards may be present, particularly from short
circuits of the battery system.
CAUTION: The inverter is NOT reverse polarity protected—which
means if the negative and positive battery voltage is connected to the
inverter backwards, the inverter will likely be damaged. Use a voltmeter
to verify the correct polarity BEFORE connecting the DC wires.
CAUTION: DO NOT connect the battery cables to the inverter until
all wiring is complete and the correct DC voltage and polarity have
been verified.
Refer to Figure 2-4 when connecting the DC wires to the battery, and to
Figure 2-5 when connecting to the inverter. Also, consider the following
requirements to ensure maximum performance:
• The DC positive and negative cables connected to the inverter from the
battery bank should be tied together with wire ties/straps or electrical
tape approximately every 6 inches (15.3 cm). This helps improve the
surge capability and reduces the effects of inductance, which improves
the inverter waveform and reduces the wear of the inverter’s filter
capacitors. Keeping the battery cables close together also reduces the
chance of radio frequency interference.
• Be aware that over-tightening or misthreading the nuts on the DC
terminals can cause the bolts to strip and snap/break off.
• Make sure cables have a smooth bend radius and do not become kinked.
Follow existing wire runs where possible.
• Crimped and sealed copper ring terminal lugs with at least a 6 mm (1/4”)
bolt hole to connect the DC wires to the inverter’s DC terminals.
• The battery bank voltage MUST be between 10.5-15.5 for the inverter
to operate. If the voltage exceeds 16.0V, the inverter may be damaged.
• To ensure the maximum performance from the inverter, all connections
from the battery bank to the inverter should be minimized. The
exceptions are the DC fuse and disconnect, or the DC circuit breaker—
required at the battery to protect the DC wiring—in the positive line. Any
other additional connection will contribute to additional voltage drops,
and these extra connection points may loosen during use.
• A brief spark or arc may occur when connecting the battery cables to the
inverter DC terminals; this is normal and due to the inverter’s internal
capacitors being charged.
• Before routing the wiring, color code the DC cables/wires with colored
tape or heat shrink tubing: RED for positive (+); WHITE for negative (–);
and GREEN (or bare copper) for DC ground, to avoid polarity problems.
• When installed in a truck/RV, a cable should be connected directly from
the inverter’s negative terminal to the battery negative connection; this
ensures the inverter has a reliable return path directly to the battery. Do
not use the vehicle chassis in place of the battery negative connection
to the inverter.
• Where DC wiring must cross AC or vice-versa, try to make the wires at
the crossing point perpendicular (90 degrees) to one another.

© 2015 Sensata Technologies 11
2.0 Installation
2.4.1 DC Wire Sizing
It is important to use the correct sized DC wire to achieve maximum efficiency
from the system and to reduce fire hazards associated with overheating. Always
keep your wire runs as short as practical to prevent low voltage shutdowns
and to keep the DC breaker from nuisance tripping (or open fuses) because
of increased current draw. See Table 2-2 to select the minimum DC wire
size (and corresponding overcurrent device) required based on your inverter
model. The cable sizes listed in this table are required in order to reduce
stress on the inverter, minimize voltage drops, increase system efficiency, and
ensure the inverter’s ability to surge heavy loads.
If the distance from the inverter to the battery is >5 feet (1.5 m), the DC wire
will need to be increased. Longer cable distances affect the performance of the
inverter. See the lower part of Table 2-2 to determine the minimum DC wire
size needed for various distances greater than 5 feet—based on your inverter
model.
DC Wire Size Exception: In an OEM RV application, smaller DC wire (with
appropriate overcurrent protection) may be used if the inverter will only be
connected to a dedicated load, and the inverter and dedicated load have
been thoroughly tested and sold together by the OEM as a complete system.
Table 2-2, DC Wire/Overcurrent Device for Rated Use
CSW2012-X
190 amps
229 amps
#8 AWG (8.36 mm²)
#2/0 AWG (67.4 mm²)
[300 amps]
300 amps with time delay
▼
5 to 10 feet = #4/0 AWG (107 mm²)
10 to 15 feet = Not recommended
Note 1 - Maximum Continuous Current is based on the inverter’s continuous
power rating at the lowest input voltage with an inefficiency factor.
Note 2 - The grounding conductor for the DC system shall meet the sizing
requirements specified in the NEC for the application, but must be no
smaller than 8 AWG copper. In some applications (i.e., Marine installations),
the DC grounding conductor is required to be no less than one size smaller
than the wire size of the DC positive/negative cables.
Full Load C urrent
Maximum Continuous Current¹
Minimum DC Ground Wire Size
2
Minimum DC Wire Size
[90˚C rating in free air]
Maximum DC Fuse Size
Increased size for
longer distance

12 © 2015 Sensata Technologies
2.0 Installation
2.4.2 DC Overcurrent Protection
For safety reasons and to comply with electrical code regulations, DC
overcurrent protection must be provided as part of the installation. The DC
overcurrent protection device must be installed in the positive DC cable line, it
can be a fuse (with a disconnect switch) or a circuit breaker and must be DC-
rated. It must be correctly sized according to the size of DC cables being used,
which means it is required to open before the cable reaches its maximum
current carrying capability, thereby preventing a fire. The NEC requires both
overcurrent protection and a disconnect switch.
Because batteries can deliver thousands of amps in an instant during a short, a
DC-rated fuse (or circuit breaker) that has an AIC (Amps Interrupting Current)
rating that can withstand the short-circuit current without explosion or damage
is required to be installed. If a fuse is used as an overcurrent device, a Class-T
type or equivalent is highly recommended when used with inverters. A Class-T
fuse is rated for DC operation, can handle very high short-circuit currents (up
to 100,000 AIC), and has a time delay that allows for momentary current
surges from the inverter without opening the fuse. In some installations, if the
combined short-circuit current of all the batteries in the bank is determined to
be 2,700 amps or less, then an ANL type of fuse may be used—if in doubt, use
a Class-T fuse. See Table 2-2 for the fuse size (coordinated with the DC wire
size) recommended for the CSW2012-X inverter.
2.4.3 DC Grounding
The inverter should always be connected to a permanent, grounded wiring
system. The idea is to connect the metallic chassis of the various enclosures
together to have them at the same voltage potential, to reduce the possibility
for electric shock. For most installations, the inverter chassis and the negative
battery conductor are connected to the system’s ground bond via a safety
grounding conductor (bare wire or green insulated wire) at only one point in
the system. The grounding conductor for the DC system shall meet the sizing
requirements specified in the NEC for the application, but must be no smaller
than 8 AWG copper. For instance: An inverter used in a marine application under
ABYC guidelines requires the size of the DC grounding conductor to be of an
ampacity equal to or one size less than that of the DC positive conductor. See
Table 2-2 for the minimum ground wire size recommended for your inverter.
Info: If the inverter is installed in a vehicle, connect the battery
negative cable directly to the inverter’s negative terminal. DO NOT
connect the negative battery cable meant for the inverter to the
vehicle’s frame/safety ground.
2.4.4 DC Cable Connections
Do not put anything between the battery cable ring lug and the battery
post (see Figure 2-4), or the flat metal part of the inverter’s DC terminal
(see Figure 2-5). When connecting the battery cable, it should be placed
directly against the battery post or inverter terminal. Incorrectly installed
hardware causes a high resistance connection which could lead to poor
inverter performance, and may melt the cable and terminal connections.
See Table 2-1 for the torque requirements.
Info: The DC terminal and Hex nuts on the CSW2012-X are made
of stainless steel, which has a high likelihood of galling or thread
seizing while being tightened—causing the bolts to strip or to snap/
break off. To reduce this risk, use an anti-seize lubricant, tighten
the fasteners slowly (at low rpms) without interruption, and apply
only light pressure.

© 2015 Sensata Technologies 13
2.0 Installation
2.4.5 Wiring the Battery Bank
WARNING: Lethal currents will be present if the positive and
negative cables attached to the battery bank touch each other.
During the installation and wiring process, ensure the cable ends
are insulated or covered to prevent touching/shorting the cables.
Info: DO NOT connect the DC wires from the battery bank to
the inverter until 1) all DC wiring is complete, 2) the correct DC
overcurrent protection has been installed, and 3) the correct DC
voltage and polarity have been verified.
Depending upon the voltage of the batteries (6 or 12 VDC), the batteries
must be wired in series, parallel, or series-parallel to provide the correct
voltage. The interconnecting DC wires must be sized and rated exactly the
same as those used between the battery bank and the inverter.
Place the batteries as close as practical to the inverter, preferably in an
insulated and ventilated enclosure. Allow adequate space above the batteries
to access the terminals and vent caps (as applicable). Also, allow at least 1”
(2.5 cm) of space between the batteries to provide good air flow. DO NOT
mount the batteries directly under the inverter.
CAUTION: Install batteries in a well ventilated area. Batteries
can produce explosive gasses. For compartment or enclosure
installations, always vent batteries to the outside.
Info: To ensure the best performance from your inverter system,
batteries should be of the same size, type, rating, and age. Do not
use old or untested batteries.
2.4.6 Appliances and Run Time
The CSW2012-X inverter can power a wide range of household appliances
including small motors, hair dryers, clocks, and other electrical devices.
As with any appliance using batteries for power, there is a certain length
of time that it can run—this is called “run time.” Table 2-3 below provides
estimates of power consumption and run time for various appliances using a
12V-120AH battery bank.
Table 2-3, Appliance Power Consumption and Run Time
Load Consumption Estimated Run Time
Cordless Phone 5W 180 hrs
Clock/Radio 8W 135 hrs
Table Lamp 40W/60W 27 hrs/18 hrs
Freezer (8.8 cu ft) 80W 15 hrs
20” LCD TV 100W 11.5 hrs
Refrigerator (18 cu ft) 120W 9 hrs
Sump Pump (1/2 hp) 350W 3 hrs
Microwave (mid-size) 1000W 49 min
Coffee Maker 1200W 37 min

14 © 2015 Sensata Technologies
2.0 Installation
2.4.7 Wiring the Inverter to the Battery Bank
CAUTION: The inverter is NOT reverse polarity protected—if the
positive terminal of the battery is connected to the negative terminal
of the inverter and vice versa, severe damage to the inverter will
occur and this will void the warranty. Before connecting the DC wires
from the batteries to the inverter, verify the correct battery voltage
and polarity using a voltmeter. If necessary, color code the cables
(with colored tape): red for positive (+), and white for negative (-)
to avoid polarity confusion.
Info: The DC overcurrent device (i.e., circuit breaker or fuse) must
be placed in the positive (red) DC cable line between the inverter’s
positive DC terminal and the battery’s positive terminal (red)—as
close to the battery as possible. For maximum protection, install it
within 18 inches (45 cm) of the battery.
Follow the steps below to wire the inverter to the battery bank:
1. Route an appropriately sized DC negative wire (marked white) from the
negative terminal of the battery bank to the inverter’s negative terminal
(Figure 1-3; Item 15).
2. Mount the fuse/disconnect assembly (or circuit breaker) as near as
practical to the batteries and leave open (i.e., no power to inverter).
WARNING: DO NOT close the DC circuit breaker or connect the
fuse to connect battery power to the inverter at this time. This will
occur after the installation is complete.
CAUTION: If connecting live battery cables to the inverter DC
terminals, a brief spark or arc may occur; this is normal and due
to the inverter’s internal capacitors being charged.
3. Route and connect an appropriately sized DC positive wire (marked red)
from the inverter’s positive DC terminal (Figure 1-3; Item 14) to one
end of the fuse/disconnect assembly (or circuit breaker).
4. Connect a short wire (same rating as the DC wires) to the other side of
the DC circuit breaker (or one end of the fuse/disconnect assembly) and
the other end of that short wire to the positive terminal of the battery
bank (see Figure 2-1 for reference). This is essential to ensure even
discharging across the entire battery bank.
5. Ensure the DC wire connections (on the batteries, inverter, and DC
circuit breaker/fuse) are flush on the surface of the DC terminals, and
all hardware used to hold these connections are stacked correctly (see
Figures 2-4 and 2-5). Verify all DC connections on the inverter are torqued
correctly (see Table 2-1), and the total cable distance from the inverter to
the battery is within the requirement of Section 2.4.1 (DC Wire Sizing).
6. Once the DC connections are completely wired and tested, coat the
terminals with an approved anti-oxidizing spray.
7. If the batteries are in an enclosure, perform a final check of the connections
to the battery terminals, then close and secure the battery enclosure.
8. Route an appropriately sized DC ground wire (see Table 2-2) from the
inverter’s DC chassis ground connection to a dedicated system ground.
9. Once the entire installation is complete and all connections verified, close
the fuse disconnect (or circuit breaker) to provide power to the inverter.

© 2015 Sensata Technologies 15
2.0 Installation
Figure 2-5, DC Cable to Inverter’s DC Terminals
Inverter’s DC
+ terminal
M8-1.25 Hex nut
CAUTION:
Ensure nothing is placed
between the DC terminal
and the ring lug.
CSW2012-X
Inverter
Lock washer
DC cable
with ring lug
BATTERY
DC cable
with ring lug
bolt
flat washer
nut
lock washer
battery
post
battery terminal
Verify that the
DC cable lugs are flush
with the battery terminals.
Figure 2-4, DC Cable to Battery Terminals