CPAP usage

Be aware that some brands/models of CPAP units are designed to operate only on 120 volts AC or on a proper capacity inverter from 12 volt DC. Some CPAP units will work on 12 volts dc via a cord with a proper connector that plugs directly into the CPAP unit (BUT) the connector must be wired to provide the proper polarity of 12volt dc power required by the CPAP unit. My older Res Med Auto Set CPAP requires the center contact to be wired as negative and outer contact as positive. If you have wrong polarity, CPAP unit may be damaged. There is little standardization of CPAP power requirements. I think that some CPAP makers want to sell you an expensive portable battery pack and charger. It is important to understand alternate power requirements for RV use as well as when you have a power outage, wherever you happen to be. PS: Important: If you must use your CPAP in a hospital, make special arrangements with your surgeon and hospital staff to use your personal CPAP in the hospital room after surgery. A respiratory technician may need to inspect and OK your CPAP unit for use for legal reasons. PS: if you don't need to use the heated humidifier attachment, you may not need 120volt AC power and may be able to run on 12 volt dc battery power.