The ResMed AirSense series is the most widely used CPAP machine among American travelers. Whether you have an AirSense 10, the newer AirSense 11, or even the compact AirMini, the question before every international trip is the same: do I need a voltage converter, or just a plug adapter?
Since the ResMed S9 series launched in 2011, every ResMed CPAP has shipped with a universal-voltage power supply. That means the power brick โ not the machine itself โ handles the voltage difference between US outlets (120V) and European or Asian outlets (220-240V). This guide walks through the exact specs, explains why your humidifier changes the power math, and lays out a clear decision path so you pack the right gear. For a broader look at all CPAP brands and travel, see our CPAP Europe travel guide.
AirSense 10 vs. AirSense 11: Power Specs Compared
| Specification | AirSense 10 | AirSense 11 | AirMini |
|---|---|---|---|
| Power Supply INPUT | 100-240V ~ 50-60Hz | 100-240V ~ 50-60Hz | 100-240V ~ 50-60Hz |
| Power Supply OUTPUT | 24V DC, 3.75A (90W) | 24V DC, 3.75A (90W) | 24V DC, 0.83A (20W) |
| CPAP Only | ~30-53W | ~25-48W | ~12-30W |
| + HumidAir Humidifier | ~55-85W | ~50-80W | N/A (passive HumidX) |
| + HumidAir + ClimateLineAir | ~75-105W | ~70-100W | N/A |
| Connector Type | Barrel plug A (proprietary) | Barrel plug B (proprietary) | Unique small connector |
| Weight (with humidifier) | 2.75 lbs / 1.25 kg | 2.27 lbs / 1.03 kg | 0.66 lbs / 0.30 kg |
| Dual Voltage? | Yes - 100-240V | Yes - 100-240V | Yes - 100-240V |
| Converter Needed? | No - adapter only | No - adapter only | No - adapter only |
All three models accept any voltage from 100V to 240V automatically. The power supply does the conversion internally โ you do not need a voltage converter for the CPAP itself. You only need a plug adapter to match the outlet shape at your destination.
One critical detail: the AirSense 10 and AirSense 11 use different barrel-plug connectors. Their power supplies are not interchangeable. If you own both machines, make sure you pack the correct power supply.
Total power draw by configuration โ all setups stay within the 90W power supply capacity because the heating elements cycle on and off rather than running continuously.
How to Read Your CPAP Power Label
The voltage information is printed on the power supply brick (the rectangular block on your power cord), not on the CPAP machine itself. Flip the brick over and look for a line like this:
Here is what each part means:
- 100-240V โ This is a wide-voltage (dual-voltage) power supply. It automatically adjusts to any voltage from 100V to 240V. No converter needed.
- 50/60Hz โ Compatible with both US frequency (60Hz) and European/Asian frequency (50Hz).
- 24V DC output โ The CPAP runs on direct current. The power supply has already converted AC from the wall to clean DC for the machine.
If you see 100-240V on the label, your power supply is travel-ready worldwide. Every ResMed CPAP shipped since the S9 series (2011) uses this type of universal power supply.
Do You Need an Adapter, a Converter, or a Battery?
CPAP travelers often confuse these three terms. Here is what each one actually does:
| Device | What It Does | Do You Need It for CPAP? |
|---|---|---|
| Plug Adapter | Changes plug shape to fit a foreign outlet. Does not change voltage. | Yes โ every country with a different outlet shape. |
| Voltage Converter | Converts AC voltage from one level to another (e.g. 220V to 110V). | No โ your ResMed PSU handles 100-240V internally. |
| Pure Sine Wave Converter | Converts voltage while producing a clean, smooth AC waveform. | Optional โ adds power protection on unstable grids. |
| CPAP Battery | Supplies DC power directly, bypassing the wall outlet entirely. | Optional โ flights, camping, or power outages. |
Bottom line: For most international trips, a plug adapter is the only thing you need. A pure sine wave converter or CPAP battery is a "nice to have" โ the sections below explain when each one makes sense.
Why a Humidifier Changes the Power Equation
Running the AirSense motor alone draws just 25-53W depending on pressure. Most users travel with the HumidAir heated humidifier attached, which adds a heating plate that warms the water chamber. At maximum settings, total draw reaches 80-85W.
Adding the ClimateLineAir heated tube pushes the total to roughly 100-105W at peak. This stays within the 90W power supply's capability because the heating elements use a duty-cycle pattern โ they switch on and off in short intervals rather than drawing full power continuously.
Pure Sine Wave vs. Modified Sine Wave: Why It Matters for CPAP
A CPAP machine uses a brushless DC motor (BLDC) controlled by a microprocessor. The motor speed directly sets the air pressure โ accuracy is a medical requirement. Although the ResMed power supply converts AC to DC internally, the quality of the AC input affects the cleanliness of the DC output.
| Power Source | Waveform | Effect on CPAP |
|---|---|---|
| Home wall outlet | Pure sine wave (smooth, continuous) | Ideal โ motor runs quietly, electronics stable |
| Stable foreign grid + plug adapter | Pure sine wave | Good โ same quality as home |
| Pure sine wave converter | Electronically generated smooth AC | Safe โ filters grid noise, protects motor |
| Unstable grid (direct) | Voltage spikes, brownouts, frequency drift | Risk โ may cause error codes or shorten PSU lifespan |
| Modified sine wave inverter | Stepped, blocky waveform with harmonics | Not recommended โ motor buzz, heating issues, error codes |
| CPAP battery (DC direct) | Pure DC โ bypasses AC entirely | Ideal โ cleanest possible power |
A pure sine wave is the smooth alternating-current waveform from a standard wall outlet โ what your CPAP power supply was designed to receive. A modified sine wave is a cheaper approximation where the waveform jumps in blocky steps. The extra harmonics can increase DC output ripple from the power supply, potentially causing motor hum, reduced humidifier performance, or โ in rare cases โ error codes.
Pure sine wave (smooth) vs. modified sine wave (stepped). CPAP motors are designed for smooth AC input.
When does a pure sine wave converter matter? Not for most trips. If you are going to Western Europe, Japan, or Australia, plugging in with a simple adapter is fine. A pure sine wave converter becomes valuable when:
- You are traveling to a region with known power instability โ parts of Southeast Asia, sub-Saharan Africa, rural South America, or India.
- You are staying in a safari lodge, remote resort, or hostel running on a generator.
- You want a peace-of-mind buffer for a multi-week trip where replacing a damaged PSU would be difficult.
When You Do Not Need Anything Beyond a Plug Adapter
ResMed's own travel page recommends bringing a plug adapter โ and nothing else. That advice is correct for most destinations. If your trip checks all of these boxes, a plug adapter is all you need:
- Destination has a stable national power grid (Western Europe, Japan, Australia, Singapore, South Korea).
- You are staying in a hotel or modern accommodation with grounded outlets.
- You are using the original ResMed power supply (not a third-party replacement).
Thousands of CPAP users travel to Europe every year with nothing more than a plug adapter and report zero issues. The ResMed power supply's 100-240V range covers every country on Earth.
What about a CPAP battery instead of a converter? Batteries are excellent for flights and off-grid situations, but they are not a replacement for wall power during a hotel stay. The ResMed Power Station II lasts about 13 hours with CPAP only but only 3 hours with the humidifier at maximum. A Medistrom Pilot-24 Lite offers similar trade-offs. Batteries are a backup tool, not a nightly power solution.
Recommended Power Setup by Scenario
Stable grids: Europe, Japan, Australia, Singapore
A plug adapter is all you need. The AirSense power supply handles voltage and frequency internally.
Variable grids: Southeast Asia, Africa, South America, India
Use a pure sine wave converter for cleaner, more stable AC power. The DOACE LC-X35 provides 350W of pure sine wave output โ more than 3x the full AirSense system draw โ plus frequency conversion and USB charging ports.
Off-grid: flights, camping, power outages
Use a CPAP battery. The ResMed Power Station II is designed for the AirSense 11. Third-party batteries like the Medistrom Pilot-24 Lite work with both models. Keep the battery under 100Wh to comply with FAA lithium battery regulations.
DOACE 70W GaN Travel Adapter
Best fit: AirSense 10/11 owners traveling to stable-grid countries who only need a plug adapter plus USB-C charging for phone and laptop.
Not for: Destinations with known power instability โ a plug adapter alone does not filter voltage spikes or waveform noise.
DOACE LC-X35 Pure Sine Wave Converter (350W)
Best fit: CPAP users traveling to countries with unreliable power grids who want the cleanest possible AC input. 350W capacity handles the full AirSense system with ample headroom.
Not for: Trips to stable-grid countries where a simple plug adapter is sufficient โ carrying extra weight and cost for minimal benefit.
Airline and TSA Guidelines for CPAP Travel
- CPAP does not count as a carry-on: Under TSA rules and most international airline policies, a CPAP machine is classified as a medical device and does not count toward your carry-on bag limit.
- Remove it at security: Place the CPAP in a separate bin at the security checkpoint, similar to a laptop.
- Carry a medical device letter: Have a letter from your doctor confirming the CPAP is prescribed. Some international airlines require this.
- Never check CPAP in luggage: Always carry it on. Checked bags face temperature extremes and rough handling.
- Empty the water chamber: Drain the HumidAir before flying. Refill with distilled water at your destination โ most hotel front desks or local pharmacies can provide it.
- In-flight CPAP use: You need a seat with an AC outlet or a CPAP battery. Contact your airline at least 48 hours before departure.
CPAP Travel Checklist
Print this or screenshot it before your trip:
- Confirm your power supply label says 100-240V ~ 50/60Hz
- Pack the correct power supply (AirSense 10 and 11 PSUs are not interchangeable)
- Buy a plug adapter for your destination country
- If traveling to an unstable-grid region, pack a pure sine wave converter
- Empty the HumidAir water chamber
- Plan how to get distilled water at your destination
- Print or save a medical device letter from your doctor
- Confirm your seat has an AC outlet if you need CPAP in-flight
- Contact your airline in advance if using CPAP during the flight
- Pack the CPAP in your carry-on โ never check it
- At security, place the CPAP in a separate screening bin
- If using a battery, confirm it is under 100Wh (FAA limit)
AirSense 10 vs. 11: Which Is Better for Travel?
| Travel Factor | AirSense 10 | AirSense 11 |
|---|---|---|
| Weight (with humidifier) | 2.75 lbs / 1.25 kg | 2.27 lbs / 1.03 kg |
| Size | Larger footprint | ~30% smaller |
| Noise level | 26.6 dBA | 25 dBA |
| Dual voltage? | Yes โ identical range | Yes โ identical range |
| Battery support | Third-party batteries only | Native ResMed Power Station II |
| Connectivity | SD card + cellular | Bluetooth + Wi-Fi + cellular |
| PSU interchangeable? | No โ different connector | No โ different connector |
The AirSense 11 is lighter, smaller, quieter, and has native battery support โ making it the better travel machine. But both models share the same voltage compatibility. If you already own an AirSense 10, there is no power-related reason to upgrade just for travel.
AirSense 11 scores higher on portability and battery support, but both are equally voltage-compatible.
Frequently Asked Questions
Do I need to bring the original ResMed power supply?
Yes. Always travel with the original ResMed power supply. Third-party PSUs may not provide the correct voltage/current and could void your ResMed warranty. The original PSU is already dual-voltage (100-240V), so there is no benefit to replacing it.
Can I use my AirSense on an airplane?
Most airlines allow in-flight CPAP use. You need a seat with an AC outlet (usually business or premium economy) or a CPAP battery. Contact your airline at least 48 hours before departure. Some carriers require a medical device letter.
What plug adapter do I need for Europe?
Continental Europe uses Type C or Type F outlets. The UK uses Type G. A DOACE universal travel adapter covers all of these plus Australia, Japan, and more. For outlet photos, see our European hotel outlet guide.
My humidifier makes a buzzing noise abroad. Is that normal?
A faint hum from the HumidAir heating plate is normal on 50Hz power (vs. 60Hz at home). It does not affect therapy pressure or machine safety. If it bothers you, a pure sine wave converter outputting 60Hz eliminates the noise.
Is the ResMed AirMini also dual-voltage?
Yes. The AirMini power supply is rated 100-240V, 50-60Hz. It weighs only 0.66 lbs and draws up to 30W โ the lightest travel CPAP option. It uses passive HumidX moisture exchange instead of a heated humidifier, so there are no heated-accessory power concerns.
Will using a converter void my ResMed warranty?
ResMed requires use of the original power supply. When you use a pure sine wave converter, the converter feeds clean AC to the original ResMed PSU, which then outputs 24V DC to the CPAP. The original PSU stays in the power chain. ResMed has not publicly stated that this voids the warranty, but has not explicitly endorsed it either. In practice, this setup is electrically equivalent to plugging into a clean wall outlet.
Do I need a surge protector?
A basic surge protector helps in areas with power spikes but does not filter waveform quality. If you are concerned enough to carry a surge protector, a pure sine wave converter does more โ it provides surge protection, voltage regulation, and waveform filtering in one device.
Where can I get distilled water abroad?
Ask the hotel front desk โ many international hotels stock distilled water for guests with CPAP machines. Otherwise, check local pharmacies. In a pinch, bottled drinking water works for a night or two, though mineral deposits may build up over time. For CPAP travel tips from other users, see our CPAP user community guide.
