Cobra CPI500W Power Inverter, 500 Continuous / 1000 Peak

The Cobra CPI500W POWER 500W inverter converts power from a 12-volt battery into 115-volt AC power for laptops, entertainment electronics, mobile-device chargers and compatible small appliances. It provides 500 watts of continuous modified sine wave output and up to 1,000 watts of peak power, with two GFCI-protected AC receptacles and separate USB-A and USB-C fast-charging ports. Full output requires the supplied direct-to-battery cables; output is limited to 180 watts when using the included 12-volt accessory-plug cable.

Key Features

• 500-watt continuous AC output
• 1,000-watt peak output for brief startup loads
• Approximately 90% conversion efficiency
• Modified sine wave AC output
• Two GFCI-protected 115-volt AC outlets
• One USB-A and one USB-C 15-watt fast-charge port
• Direct-to-battery cables included for full-rated output
• 12-volt accessory-plug cable included for loads up to 180 watts
• Automatic temperature-controlled cooling fan
• Cobra Pentagon Protection safety system
• Compatible with an optional Cobra remote controller
• Two-year manufacturer warranty

Intended Use

The CPI500W is suitable for operating or charging compatible equipment such as:

• Laptop computers and chargers
• Smartphones and tablets
• Televisions and entertainment devices
• Fans
• Lighting
• Small appliances
• Mini refrigerators with suitable startup requirements
• Other equipment rated for modified sine wave power

The total operating load must remain below 500 watts. Devices with motors, compressors or heating elements may draw substantially more than their listed running wattage during startup.

Technical Specifications

• Manufacturer: Cobra Electronics
• Model: POWER 500W
• Part number: CPI500W
• DC input: 13 volts nominal
• AC output: 115 volts
• AC frequency: 60 Hz
• Continuous power: 500 watts
• Peak power: 1,000 watts
• Maximum AC output current: 4.3 amps
• Output waveform: Modified sine wave
• Efficiency: Approximately 90%
• No-load current draw: Less than 0.6 amp
• Low-battery alarm: Approximately 10.5 volts
• Low-battery shutdown: Approximately 9.5 volts
• AC outlets: Two GFCI protected
• USB ports: One USB-A and one USB-C

USB Charging Output

• USB-A: 5V/3A or 9V/1.67A
• USB-C: 5V/3A or 9V/1.67A
• Fast-charge rating: Up to 15 watts per supported port and device

Charging performance depends on the connected device, charging cable and supported charging protocol.

Built-In Protection

Cobra’s Pentagon Protection system includes protection for:

• Excessive operating temperature
• Reverse-polarity connection
• Excessive input voltage
• Low-voltage warning
• Low-voltage shutdown

The inverter also incorporates overload, short-circuit and GFCI protection. Reverse-polarity protection does not replace the need to verify cable polarity before connecting the inverter.

Dimensions and Weight

• Height: 7.01 inches / 178.1 mm
• Width: 5.39 inches / 137 mm
• Depth: 2.83 inches / 71.9 mm
• Weight: 1.41 lb / 640 g
• Direct-battery cable length: 16 inches
• Accessory-plug cable length: 16 inches

Operating Temperature

• Operating range: 14°F to 104°F / -10°C to 40°C
• Storage range: -40°F to 149°F / -40°C to 65°C
• Cooling: Automatic temperature-controlled fan

The fan operates only when internal temperature requires additional cooling; it may remain off during light-load operation.

Fitment Notice

The CPI500W is designed for a nominal 12-volt battery system. Do not connect it to a 24-volt or 48-volt battery bank.

The included connection method determines the available output:

• Direct battery cables: Required for loads approaching the full 500-watt rating
• 12-volt accessory cable: Limited to 180 watts by its 15-amp fuse and the capacity of the accessory socket

This inverter does not include a battery charger, automatic shore-power transfer switch or permanent marine AC distribution connection.

Modified Sine Wave Notice

The CPI500W does not produce utility-grade pure sine wave power. It works with many conventional power supplies and appliances, but may be unsuitable for:

• Medical equipment
• Sensitive audio systems
• Variable-speed motors
• Electronically controlled appliances
• Certain battery chargers
• Digital timing devices
• Equipment whose manufacturer specifies pure sine wave power

Select a pure sine wave inverter when the connected equipment requires cleaner AC output.

Installation Notes

Place the inverter in a dry, ventilated location protected from rain, spray, bilge water, excessive heat, battery gases and fuel vapours. Do not block the cooling openings.

Turn the inverter off before connecting the battery cables. Verify positive and negative polarity before completing the connection.

For full-power use, connect the unit directly to the battery with the supplied cables. Permanent marine installations should include properly rated overcurrent protection near the battery and wiring installed according to applicable marine electrical standards.

Included Components

• Cobra CPI500W power inverter
• 16-inch #10 AWG direct-to-battery cables
• 16-inch 12-volt accessory-plug cable with 15-amp fuse
• Quick-start or operating documentation

A battery fuse, fuse holder and remote controller are not included.

When This Product Needs Replacement

Inspect or replace the inverter if it:

• Repeatedly shuts down under correctly sized loads
• No longer provides stable AC output
• Has damaged GFCI outlets or USB ports
• Shows melted, loose or heat-damaged terminals
• Produces smoke, unusual odour or excessive heat
• Has visible moisture intrusion or corrosion
• Repeatedly reports low voltage with a verified healthy battery
• Has a cooling fan that no longer operates when the inverter becomes hot

Before replacing the unit, inspect the battery condition, cable polarity, accessory-plug fuse, terminal tightness and voltage drop under load.

Alternate Part Numbers

• Cobra part number: CPI500W
• Product name: POWER 500W
• UPC: 028377315558
• Crutchfield reference: 036500W

Parts Desk Insight

The CPI500W can only deliver its full 500-watt rating when connected directly to the battery. The included accessory-plug cable is convenient for smaller electronics, but is restricted to 180 watts. For sensitive electronics, electronically controlled equipment or appliances requiring household-quality AC, choose a pure sine wave inverter instead.