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POWER YOU CAN TRUST
With a range of 400 to 3000 Watts, our family of reliable and dependable power inverters provides the power you need, whether it’s to work, play, or get away.
Cobra
PURE SINE 400W
Pure Sine 400 Watt Power Inverter
$129.95
The PURE SINE 400W Power Inverter with Fast Charge USB is perfect for pro drivers, travelers, campers, and more who want to power medical devices like CPAP machines or sensitive electronics like laptops, gaming systems, and entertainment devices.
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Cobra PURE SINE 400W
Pure Sine 400 Watt Power Inverter
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PURE SINE 400W POWER INVERTER
With 400 Watts of Pure Sine Wave power, you'll be able to run medical equipment and sensitive electronics without any operating issues.
1Ideal for Medical Equipment & Sensitive Electronics
Pure Sine Wave output provides a clean electrical current to ensure your medical devices and electronics operate properly.
290% Efficient Pure Sine Wave
Highly efficient inverter, giving your devices and appliances longer run times and extending your vehicle’s battery life.
3400 Watts Continuous / 800 Watts Peak
400 Watts of continuous Pure Sine power with 800 Watts peak can reliably handle your medical devices and electronics.
42 GFCI Protected AC Outlets
Easily power up to 2 of your medical devices, electronics, or small appliances with GFCI protected AC outlets for each.
515W USB Fast Charge Ports
Quickly charge your smartphones, tablets, or other mobile devices from the convenient USB-A and USB-C ports.
6Pentagon Protection Safety
Built-in protection for Over Temperature, Reverse Polarity, Over Voltage, Low Voltage Alarm, and Low Voltage Cutoff.
ADDITIONAL FEATURES
2 Year Warranty
Industry-leading 2 year warranty provides complete peace of mind
COBRA REMOTE COMPATIBLE
Monitor and charge devices with Fast Charge USB from anywhere inside your vehicle
16" #12 AWG and 12V Cables Included
Includes heavy-duty direct-to-battery cable and convenient 12V accessory cable
Input/Output LED Indicator
A 2-color LED indicator lets you know your power inverter status at all times
INDUSTRY-LEADING SAFETY
When you need safe and reliable portable power,nothing comes close to a Cobra
Rugged Industrial Design
Designed to look and work great in your car, truck, RV, or semi
POWER WHERE YOU NEED IT
Our POWER 500W power inverter is small enough to fit just about anywhere but capable enough to charge and power your devices and small appliances.
PRO DRIVERS CAN COUNT ON COBRA
Our PRO 1500W, 2500W, and 3000W inverters provide all the power you might need to charge or operate devices, electronics, and standard appliances.
POWER TO GET THE JOB DONE
With our PRO series of power inverters, you’ll get the job done with 4 GFCI protected AC outlets and Cobra’s industry-leading Pentagon Protection built-in safety.
HAVE MORE FUN OUTDOORS
Whether you’re camping, tailgating, or on a road trip, you’ll have more fun outdoors knowing you can power the devices and appliances you need to entertain.
COMPARE MODELS
 PURE SINE 400W |
 POWER 500W |
 PRO 1500W |
 PRO 2500W |
 PRO 3000W |
|
|---|---|---|---|---|---|
| Output Waveform | Pure Sine | Modified Sine | Modified Sine | Modified Sine | Modified Sine |
| Continuous/Peak Power | 400W / 800W | 500W / 1000W | 1500W / 3000W | 2500W / 5000W | 3000W / 6000W |
| Perfect For | Pro Drivers Campers RV Enthusiasts |
Travelers Campers RV Enthusiasts |
Pro Drivers Campers RV Enthusiasts |
Pro Drivers Contractors Campers RV Enthusiasts |
Pro Drivers Contractors Campers RV Enthusiasts |
| Can Power | Medical Devices Sensitive Electronics Smartphones/Laptops Entertainment Devices |
Smartphones/Laptops Entertainment Devices Small Appliances |
Smartphones/Laptops Electronics Entertainment Devices Kitchen Appliances |
Smartphones/Laptops Electronics Entertainment Devices Power Tools Kitchen/Bath Appliances |
Smartphones/Laptops Electronics Entertainment Devices Power Tools Kitchen/Bath Appliances |
| GFCI Protected AC Outlets | 2 | 2 | 4 | 4 | 4 |
| Volt/Watt Meter | 2-Color LED | 2-Color LED | 7-Segment LED Display | 7-Segment LED Display | 7-Segment LED Display |
| Included Cables | 16' #12 AWG and 12V Cables | 16' #10 AWG and 12V Cables | (2) 48" #4 AWG Cables | (4) 48" #4 AWG Cables | (4) 48" #2 AWG Cables |
| Cooling Fans | 1 | 1 | 2 | 2 | 2 |
| Cobra Remote Controller with Fast Charge USB | Compatible | Compatible | Compatible | Compatible | Included |
| 3.0 Amp USB Fast Charge Ports | USB-A / USB-C | USB-A / USB-C | USB-A / USB-C | USB-A / USB-C | USB-A / USB-C |
| Efficiency Rating | 90% | 90% | 90% | 90% | 90% |
| Pentagon Protection Safety | |||||
| 2 Year Warranty | |||||
| cETL Certified | |||||
| Terminal Protector Boots | |||||
| Mounting Kit for Remote Controller | |||||
POWER WHERE & WHEN YOU NEED IT
Cobra's family of power solutions are the safe, reliable way to provide you with power, wherever and whenever you need it. With advanced technology and built-in safety protection, you can always count on Cobra for your power needs.
WHAT'S IN THE BOX
Included with your PURE SINE 400W power inverter are 16" #12 AWG power cables and a 16" 12-Volt accessory cable.
Item # CPI400PSW
Continuous Power: 400W
Surge Power: 800W
Efficiency Rating: 90%
No-load draw: < .6A
Output Waveform: Pure Sine Wave*
* Some packages may mistakenly list the Output Type as “Modified Sine Wave”. This is incorrect and should be Pure Sine Wave.
Input Voltage Range: 10.5 - 15.0V DC
Output: 115V AC, 60Hz, 3.4A, 400W
Low Voltage Alarm: 10.5V DC
Low Voltage Cut-Off: 9.5V DC
AC Receptacles: 2 GFCI Protected AC Outputs
Fast Charge USB-A Output: 5V/3.0A, 9V/1.67A Fast Charge
Fast Charge USB-C Output: 5V/3.0A, 9V/1.67A Fast Charge
Remote-Ready Output Port: Yes
Remote Included*: No
*Sold Separately
12V Vehicle Accessory Cable: Yes
Includes Direct-to-Battery Cables: Yes
Direct-to-Battery Cables: 16" #12 AWG Cables
Thermal Shut-Down: Yes
Reverse Polarity Protection: Yes
Volt/Watt Meter: 2-Color LED
Warranty: 2 Year
Package Type: Gift Carton
Product Weight: 1.98 lbs
Product dimensions: 8.86" H x 5.39" W x 2.83"D
Package dimensions: 11.02" W x 9.06" H x 3.15" D
Master pack quantity: 6
Master pack dimensions: 10.24" H x 11.42" W x 18.90" D
Master pack weight: 16.04 lbs
UPC: 0 28377 31556 5
Master pack barcode: 2 00 28377 31556 9
The fan does not run
This is normal. The fan will only run when needed, if the inverter starts to get hot.
The output voltage is low
The voltage from your inverter is a little different than the voltage in your home. The voltage in your home is called a “sine wave”, while the voltage from the inverter is a “modified sine wave”. Because of this difference, you will need a meter that measures “true RMS” voltage. If your meter does not measure “true RMS”, then it will read low.
If it does not say “true RMS” on the front of your meter, then it is not a true RMS meter and it will read low.
My outlet tester shows an open ground
Outlet testers are intended for testing normal utility power in your home. With normal utility power, the neutral and ground are connected together in your fuse box. Outlet testers are designed under this assumption.
The outlet on your power inverter, however, is not configured exactly the same as in your home. It is normal for an outlet tester to show an open ground. This does not indicate a problem with your inverter.
Does it matter where I mount my inverter?
Your power inverter is not weatherproof, so it needs to be installed where it will be protected from heat and moisture. Keep a minimum 1 inch clearance around the inverter for ventilation.
The inverter can be mounted in any position -- horizontal, vertical, or upside-down.
My inverter makes a squealing sound (alarm sound)
If the battery voltage gets too low, your inverter will sound a low-voltage alarm. This can happen for any of the following reasons:
-The battery is low and needs to be charged
-A loose connection with the battery cables
-A loose connection in the cigarette socket (if you are using a cigarette power cord)
-The battery cables to the inverter are too small
-The appliance is pulling excessive power from the battery
If you get low voltage alarm then try running the engine so that the alternator is supplying extra power. If you get the alarm even with the alternator running, then check all the cable connections. There might be a loose connection somewhere.
How much power can I draw from each AC outlet?
If your inverter has more than one AC outlet, the full inverter power is available from any of the outlets.