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Accessories & upgrades
Find installation kits, chargers, and other accessories made to complement Cobra power products.
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Cobra PURE SINE 400W
Pure Sine 400 Watt Power Inverter
Discounts for Military, First Responders, Teachers and Students through
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Discounts for Military, First Responders, Teachers and Students through
See Terms
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Power You Can Trust
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 for clean electrical current to ensure sensitive electronics operate properly
290% Efficient Pure Sine Wave
Highly efficient inverter, giving longer run times and extending battery life
3400 Watts Continuous / 800 Watts Peak
Reliably handle your medical devices and electronics
42 GFCI Protected AC Outlets
Easily power up to 2 of medical devices, electronics, or small appliances
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
What's in the box?
Included with every new Cobra PURE SINE 400W:
- Pure Sine 400W 12v Power Inverter
- 16" #12 AWG direct-to-battery power cables
- 16" 12-volt accessory power cable
- Product Manual
Product help, tech support, and more
Take your knowledge to the next level. Get information and product support all in one convenient location.
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.