Cobra CPI 2550 User manual

A1 English
Our Thanks to You
Introduction
Thank you for purchasing the Cobra CPI 2550
inverter. Properly used, this Cobra product
will give you many years of reliable service.
How Your Cobra Power Inverter Works
The obra power inverter is an electronic product that has
been designed and built to take low voltage D (Direct
urrent) power from your automobile or other low voltage
power supplies and convert it to standard 115 volt A
(Alternating urrent) power like the current you have in
your home. This conversion process thereby allows you
to use many of your household appliances and electronic
products in automobiles, RVs, boats, tractors, trucks and
virtually anywhere else.
Customer Assistance
Should you encounter any problems with this product,
or not understand its many features, please refer to this
owner’s manual. If you require further assistance after
reading this manual, obra Electronics offers the
following customer assistance services:
For Assistance in the U.S.A.
Automated Help Desk English only.
24 hours a day, 7 days a week 773-889-3087 (phone).
Customer Assistance Operators English and Spanish.
8:00 a.m. to 6:00 p.m. T, Monday through Friday
(except holidays) 773-889-3087 (phone).
Questions English and Spanish.
Faxes can be received at 773-622-2269 (fax).
Technical Assistance English only.
www.cobra.com (on-line: Frequently Asked Questions).
English and Spanish. [e-mail] (e-mail).
For Assistance Outside the U.S.A.
Contact Your Local Dealer
Customer Assistance
©2005 Cobra®Ele troni s Corporation
6500 West Cortland Street
Chi ago, Illinois 60707 USA
www. obra. om
Operating Instructions
Nothing comes close to a obra®English
2500 WATT POWER INVERTER
CPI 2550
Printed in hina
Part No. 480-200-P
Version A
Nothing comes close to a obra®English
For more information or to
order any of our products,
please visit our website:
www.cobra.com
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Radar/Laser Detectors
Safety Alert®Traffic Warning Systems
Handheld GPS Receivers
Mobile GPS Navigation Systems
HighGear®Accessories
CobraMarine™VHF Radios
Power Inverters
Accessories
The Cobra line of quality
products includes:

Features
•Three AC Receptacles
•Current eter
•Remote On/Off Capable
•Automatic Thermal
Protection/Shutdown
•Reverse Polarity Protection
•Low Battery Alarm
•Low Battery Shutdown
A3 English
A2 English
Product Features
Introduction Introduction
AC Outlets
Current
Meter
Positive Battery
Cable Terminals
(Red)
Negative Battery
Cable Terminals
(Black)
Ground
Terminal
Cooling Fans
Contents
Introduction
Our Thanks to You . . . . . . . . . . . . . . . . . . A1
ustomer Assistance . . . . . . . . . . . . . . . . A1
Product Features . . . . . . . . . . . . . . . . . . . A2
Important Safety Information . . . . . . . . . . . 1
Quick Evaluation Before Installation . . . . . . .4
Installation
Installation Requirements . . . . . . . . . . . . . . 6
Mounting ..........................7
onnecting ables . . . . . . . . . . . . . . . . . . . 8
Power onsumption . . . . . . . . . . . . . . . . . 12
GroundWiring .....................13
Operation
Turning Your Inverter On or Off . . . . . . . . 14
Remote On/Off Switch . . . . . . . . . . . . . . . 15
Power and Protection Indicators . . . . . . . 16
OperatingLimits ....................17
Troubleshooting Guide . . . . . . . . . . . . . . . 18
Specifications ......................19
Warranty
Warranty..........................20
Customer Assistance
Maintenance........................21
ProductService ....................21
Accessories and Order Form . . . . . . . . . . 22
On/Off Power
Switch
Remote
On/Off
Switch
ack
Power & Protection
Indicators

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Introduction Important Safety Information
Important Safety Information
•
Before installing and using your Cobra power inverter,
please read these general precautions and warnings.
Caution and Warning Statements
To make the most of this inverter, it must be installed and
used properly. Please read the installation and operating
instructions carefully before installing and using it. Special
attention must be paid to the CAUTION and WARNING
statements in the manual.
CAUTION Statements specify conditions which
could cause damage to the unit or other equipment.
WARNING Statements identify conditions that
could result in personal injury or loss of life.
General Precautions
1. Never install the inverter in a boat’s engine compartment
where gas and battery fumes are present.
2. Do not operate the inverter if it has been
dropped or damaged in any way.
3. Do not open the inverter; it contains no
user-serviceable parts. Attempting to service
unit could cause electrical shock.
NOTE Internal components remain
charged after all power is disconnected.
4. Do not expose the inverter to rain, snow,
bilge water or spray.
5. Do not obstruct the ventilation openings.
6. Do not install the inverter in zero-clearance
compartment.
CAUTION This inverter should be used in
negative ground applications only.
CAUTION

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Important Safety Information
Introduction
WARNING Power inverters contain components
that tend to produce arcs or sparks. To prevent
fire or explosion, do not install the inverter in
areas or compartments containing batteries or
flammable materials or in locations that require
ignition-protected equipment.
WARNING To reduce the risk of fire, do not cover
or obstruct the ventilation openings. Do not install
inverter in zero-clearance compartment.
Caution: Rechargeable Appliances
ertain chargers for small nickel cadmium batteries
can be damaged if connected to the obra 2500 watt
inverter. Two particular types of equipment are
prone to this problem:
1. Small battery-operated appliances
such as flashlights, razors, and
night lights that can be plugged
directly into an A receptacle to
recharge.
2. ertain battery chargers for
battery packs used in hand
power tools. These chargers have
aWARNING label stating that
dangerous voltages are present
at the battery terminals.
This problem does not occur with the vast majority of
battery operated equipment. Most use a separate charger
or transformer that is plugged into the A receptacle and
produces a low voltage output. If the label on the A
adapter or charger states that it produces a low voltage
A or D output (less than 30 volts), the inverter will
have no problem powering the adapter safely.
Cobra 2500 Watt Output Waveform
Some very sensitive electronic equipment may not
operate satisfactory on “square wave” or “modified
sine wave.” The output waveform is referred to as
“square wave” or “modified sine wave.” It is a stepped
waveform designed to have characteristics similar
to the sine wave shape of utility power. A waveform
of this nature is suitable for most A loads (including
linear and switching power suppliers used in electronic
equipment, transformers and motors).
Plug In Directly
Dangerous Voltages
Important Safety Information
Introduction

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Quick Evaluation
Introduction Quick Evaluation Introduction
Quick Eva uation Before Insta ation
•
This section provides you with basic information about
the inverter and how to check its performance before
installation.
Be sure to have on hand:
A 12 volt D power source (such as a vehicle battery).
The power source must provide
between 11 and 15 volts D and be
able to supply enough current to
run the test load. As a rough guide,
divide the wattage of the test load
by 10 to get the current (in amperes)
the power source must deliver.
A set of cables to connect the power source to the
inverter (not included).
The cables must be as short and thick as possible in
order to reduce the voltage drop between the power
source and the inverter when drawing current from
the power source.
If the cable suffers an excessive voltage drop, the inverter
may shut down when drawing higher currents because
the voltage at the inverter dropped below 10 volts.
#4 AWG stranded copper cable is recommended. It
should be no longer than four feet (one and one-half
meters).
The end of the cable that connects to the inverter must
have its insulation stripped off for about one-half inch (one
and one-half cm) back from the end, exposing the bare
copper.
The other end of the cable, which connects to the power
source, must be terminated with a lug or other connector
that provides a secure, low resistance connection.
For example, if the power source is a battery, the cable
must be terminated with a battery terminal that clamps
to the post on the battery.
Power Supply
Test Load
On/Off Switch to Off
Connect Terminals
Connect Power Source
On/Off Switch to On
Connect Test Load

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Mounting
A test load that can be plugged into the A receptacle on
the inverter for short term testing at a low power level.
The following cables are recommended for testing low
power level test loads only.
Test Load inimum
Power Cable Size
100W # 16 AWG copper
250W # 12 AWG copper
500W # 8 AWG copper
To check your inverter’s performance before installation:
1. Turn the inverter off (see page 14
for details). If the power source is
a D power supply, switch it off
as well.
2. onnect cables to power input
terminals (see page 8 for details).
3. onnect cables to power source
(see page 8 for details).
4. heck to make sure all
connections are secure.
5. Turn the inverter on. If the
power source is a D power
supply, switch it on first.
6. Plug in the test load.
The inverter should supply power
to the load. If the inverter is not
working properly, refer to the
troubleshooting guide on page 18
or power and protection indicators
section on page 16.
Insta ation Requirements
•
The inverter must be installed in an area that meets
all of the following requirements:
A. Dry
Do not place in an area where water can drip
or splash on the inverter.
B. Cool
Ambient air temperature should be between 30°F
and 105°F (0° and 40° ). The cooler the better.
C. Ventilate
Allow at least one inch (three cm) of clearance around
the inverter for proper airflow. Make sure that ventilation
openings on the ends of the unit are not obstructed.
D. Safe
Do not install the inverter in the same compartment
as a battery or in any compartment that contains
flammable liquids such as gasoline.
E. Close to Battery
Install unit as close to battery as possible (without
being in the same compartment) to minimize the
length of cable required to connect the inverter to
the battery. It is better and cheaper to run longer
A wires than longer D wires (cables).
CAUTION To avoid fire, do not cover or obstruct
ventilation openings. Do not install inverter in a zero-
clearance compartment. Overheating may result.
CAUTION The inverter must only be connected to
batteries with a nominal output voltage of 12 volts.
It will not work with a 6 volt battery, and will be
damaged if it is connected to a 16 volt battery.
Installation
Mounting Brackets
Mounting Hardware
Installation
Requirements
Installation

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WARNING This unit contains components
which can produce arcs or sparks. To prevent
fire or explosion, do not install in compartments
containing a battery or flammable materials,
or in a location which requires ignition
protected equipment.
WARNING This unit is suitable for installation
in negative ground applications only. Do not
attempt to install to a positive ground application.
Mounting
•
To mount your inverter:
1. Place the inverter on a flat surface with the
mounting bracket against the mounting surface.
2. Mount to secure surface using mounting hardware
that is corrosion resistant (not included).
The inverter can be mounted horizontally or vertically.
Connecting Cab es (not inc uded)
•
Power wire and wiring are very important to the performance
of the inverter. Because the inverter has a low voltage,
high current input, low resistance wiring is essential
between the battery and inverter. This is so it can deliver
the maximum amount of energy to the load.
Use only copper wire. Aluminum wire has about one-third
more resistance than copper wire of the same size, plus it
is difficult to make good, low-resistance connections to
aluminum wire.
We recommend two #4 AWG copper cables (90°
insulation rating) as the minimum size for connections
between the battery and inverter.
Keep the cable length as short as possible, no more
than four feet (one and one-half meters). This will keep
the voltage drop to a minimum.
If the cable has too much voltage drop, the inverter
may shut down when drawing higher currents because
voltage at the inverter may drop below 10 volts. If you
must use longer cables, choose thicker cables, such as
#2 AWG, and trim the ends of the cable to fit the terminals.
To connect the cables between the inverter
and the battery:
1. Turn the On/Off Switch on the inverter to the off
position. If the power source is a D power supply,
switch it off as well.
2. On the end of the cable that connects to the inverter,
strip back the insulation about one-half inch (one and
Connecting Cables Connecting Cables
Installation Installation
On/Off Switch to Off
Strip the Insulation
Insert Bare Cables
Connect Cables

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one-half cm), exposing the bare copper conductor.
3. onnect cables to the Power Input Terminals on right
side panel of the inverter. The red terminals are positive
(+) and the black terminals are negative (-). Insert the
bare ends of the cables into the terminals and tighten
the screws to clamp the wires safely.
4. onnect cables to the power source:
a. onnect each cable from the Negative (Black)
Terminals of inverter to the Negative Terminal
of the power source. Make a secure connection.
b. onnect each cable from the Positive (Red)
Terminals of the inverter to the Positive Terminal
of the power source (the battery’s main fuse or
the battery selector switch, if you are using one).
Make a secure connection.
You might observe a spark when you make this connection,
since current can flow to charge capacitors in the inverter.
All power connections to your obra inverter must be
Positive to Positive and Negative to Negative.
CAUTION Electrical installations must meet
local and national wiring codes, and should
be performed by a qualified electrician.
CAUTION Do not connect the inverter and another
A source (such as a generator or utility power)
to the A wiring at the same time. The inverter
will be damaged if its output is connected to A
voltage from another source. Damage can even
occur if the inverter is switched off.
CAUTION Do not connect the inverter to an A
branch circuit that has high-power consumption
loads. It will not operate electric heaters, air
conditioners, stoves, and other electrical
appliances that consume more than 2500 watts.
CAUTION Loose connectors result in excessive
voltage drop and may cause over heated wires
and melted insulation.
CAUTION Reverse polarity connections (positive
to negative) will blow internal fuses in the inverter
and may permanently damage the unit. Such damage
is not covered by the warranty.
CAUTION We recommend a main fuse in the
battery’s positive cable to protect against D
wiring short circuits (external to the inverter).
The fuse should be as close to the battery as
possible. We recommend a Buss Fuse ANL-250
or equivalent. The specific fuse ampere rating
should be sized to allow operation of all your
D powered equipment.
CAUTION Remove any jewelry (watch, ring, etc.).
Be careful not to short circuit the battery with any
Connecting Cables Connecting Cables
Installation Installation

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metallic object (wrench, etc.).
WARNING If you are making a permanent A
connection to the inverter, make sure that the
A wiring steps are performed before any D
wiring is done. (D hook-up energizes internal
components, regardless of the position of the
On/Off Switch). Working on A connections in such
a circumstance may result in an electric shock.
WARNING 115 volt A power is potentially lethal.
Do not work on A wiring when it is connected to
the inverter (even if it is switched off) unless the
D power source is physically disconnected from
the inverter. Also, do not work on A wiring if it
is connected to another A power source such
as a generator or the utility line.
WARNING You may observe a spark when
making the connection because current can
flow to charge the capacitors in the inverter.
Do not make this connection in the presence
of flammable fumes. Explosion or fire may
result. Thoroughly ventilate the battery
compartment before making this connection.
NOTE If only one power source is used, connect both
cables from the negative terminal of the inverter to the
negative terminal of the power source. Then connect
both cables from the positive terminals of the inverter
to the positive terminal of the power source.
Chassis Ground
Power Consumption Ground Wiring
Installation Installation
Laptop
50 watts x 2 hours
= 100 watt-hours
TV/VCR (up to 25")
115 watts x 3 hours
= 345 watt-hours
Blender
300 watts x 15 minutes
= 75 watt-hours

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Power Consumption
•
For each piece of equipment you will be operating from the
inverter, you must determine the battery’s reserve capacity
(how long the battery can deliver a specific amount of
current — in automotive batteries, usually 25 ampere)
or ampere-hour capacity (a measure of how many amperes
a battery can deliver for a specified length of time).
Example – Reserve capacity: a battery with a reserve
capacity of 180 minutes can deliver 25 ampere for
180 minutes before it is completely discharged.
Example – Ampere-hour capacity: a battery with an
ampere-hour capacity of 100 ampere-hours can deliver
5 ampere for 20 hours before it is completely discharged.
To determine the battery ampere-hour
capacity you require:
1. Determine how many watts each piece of equipment
consumes. This can normally be found on the product
label. If only the current draw is given, multiply the
current draw by 115 to get the watt consumption.
2. Estimate the time (in hours) that each piece of equipment
will be running between battery charging cycles.
3. alculate the total watt-hours of energy consumption
(power x operating time) using the average power
consumption and the total estimated running time
(in hours). Power x Operating Time = Watt-Hours.
4. Divide the watt-hours by 10 to determine how many
power supply’s (12 volt) ampere-hours will be consumed.
Ground Wiring
•
There is a screw on the rear panel for Chassis Ground.
This is to connect the chassis of the inverter to ground.
The Chassis Ground Screw must be connected to a
grounding point, which will vary depending on where
the unit is installed. Use a #8 AWG copper wire
(preferably with green/yellow insulation) to connect
the chassis ground screw to the grounding point.
In a vehicle: onnect the Chassis Ground to the
chassis of the vehicle.
In a boat: onnect to the Boat Grounding System.
In a fixed location: onnect the Chassis Ground Screw to
earth ground by connecting to a ground rod (a metal
rod pounded into the earth) or other proper service
entrance ground.
Power On and Off
Operation Remote On/Off Switch Operation
On/Off Switch to On
Remote Switch
Remote ack
On/Off Switch to Off