macosx-ups - monitor for Mac OS X built-in UPS and battery driver


macosx-ups -h

macosx-ups -a UPS_NAME [OPTIONS]

This man page only documents the hardware-specific features of the macosx-ups driver. For information about the core driver, see nutupsdrv(8).


macosx-ups supports any USB HID Power Device Class (PDC) UPS which is matched by the Mac OS X built-in drivers. It also can monitor a laptop internal battery as though it were an UPS.

If the UPS is visible in the Energy Saver preferences pane of System Preferences, this driver should be able to monitor it.



Due to changes in the way that Mac OS X lists power sources, the port parameter no longer has any effect. The rest of NUT still requires a value here, and our traditional "don’t care" value is auto.


Likewise, if you have more than one UPS, it may be necessary to specify a model name to match against. This parameter is also a case-insensitive extended regular expression.


If the driver cannot find an UPS, first open System Preferences and see if there is an "UPS" tab on the Energy Saver panel. If so, re-run the driver with the -D flag to list the names of the power sources found.


This driver is a monitoring-only driver, and cannot shut down an UPS on its own. However, this should not be a problem in practice: it is monitoring the built-in Mac OS X UPS driver, which has configuration options for several shutdown scenarios. Consult the Energy Saver control panel or pmset(8) for more information.

The default distribution of apcupsd installs a kernel extension which prevents Mac OS X from attaching to the UPS. In order to use this driver after installing apcupsd, you must first run the apcupsd-uninstall script and reboot.

Note that other UPS monitoring solutions may show more detail than what is provided by the built-in Mac OS X driver. In particular, voltages other than the battery voltage, as well as current and frequency, are typically not shown. It may be possible to monitor these values with apcupsd (for APC hardware only) or usbhid-ups(8).


Charles Lepple <clepple+nut at>


usbhid-ups(8), pmset(8), regex(3)

The core driver:

Internet resources: