Continuous vs. Surge Output on a Power Station

Continuous output is the simultaneous load

If a 100 W heated blanket and a 65 W laptop adapter can operate at the same time, the basic simultaneous load is 165 W. Do not multiply a device by its daily duty cycle when checking output: the inverter must support the load while it is actually on.

Leave reasonable headroom and confirm the station’s total AC limit as well as any per-outlet limit. Some inverters deliver less continuous power at higher ambient temperatures, so compare the specification at conditions close to your use.

A surge number needs a duration

Motors and compressors can require more power to start than to keep running. The amount and duration are model-specific. A product may advertise a high peak that lasts only seconds, while another may publish time-limited output at several temperatures.

Use the appliance manufacturer’s startup value or a suitable meter. If several loads can start together, review that combined event instead of assuming their starts will be perfectly staggered.

Watts and VA are not interchangeable

Some AC equipment lists volt-amperes (VA), watts, or power factor. Inverter manuals may publish both VA and W ratings, and they can differ. CampWatt’s simple W estimate does not establish compatibility for equipment with a manufacturer-specified VA, power-factor, or waveform requirement.

Confirm the U.S. electrical interface

For typical U.S. household appliances, verify a 120 V / 60 Hz AC output, the correct receptacle and grounding arrangement, and any pure-sine-wave requirement. Imported appliances may be 230 V / 50 Hz or have a different plug. A mechanical plug adapter does not change voltage, frequency, grounding, or waveform.

U.S. planning limits

• CampWatt provides planning estimates, not guaranteed runtime. Actual results vary with the device, duty cycle, conversion losses, temperature, battery age, and power-station settings.
• For U.S. AC use, verify that the appliance and power station support 120 V / 60 Hz, the physical plug and grounding arrangement, and any manufacturer-specific waveform requirements. A plug adapter alone does not convert voltage or frequency.
• Do not use this calculator or these guides to size, certify, or guarantee power for medical or life-sustaining equipment. Follow the equipment manufacturer, your care provider, and your emergency backup plan.