nutdrv_atcl_usb - Man Page

Driver for 'ATCL FOR UPS' equipment


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

Supported Hardware

This driver is for UPS hardware which identifies itself as USB idVendor 0001 and idProduct 0000, and iManufacturer ATCL FOR UPS. Known manufacturers include Kanji and Plexus.

The UPS interface seems to be a generic USB-to-serial chip, and for hardware manufactured by Kanji and Plexus, the microcontroller appears to emulate a traditional contact-closure interface. This translates into only three states in ups.status: OL, OB and OB LB (similar to genericups(8)), with no other dynamic status values reported.

Note that these USB identifiers (including the iManufacturer string) have also been seen on devices that are supported by the fuji subdriver of nutdrv_qx(8).

Extra Arguments

This driver supports the following optional setting:


In case your iManufacturer (Vendor) string does not exactly match ATCL FOR UPS, you may provide an alternate string here. Note that a more likely case is that your device is handled by another driver for 0001:0000 devices, such as nutdrv_qx(8).


The UPS returns the same code for "load power is off" as for "on line power". This condition will not be observed if the NUT upsmon in primary mode runs on the box powered by the UPS, but may be an issue if the UPS is monitored by a remote (secondary) system.

The time between the shutdown command and removal of power seems to be fixed at 30 seconds. Ensure that the NUT shutdown script is invoked as late as possible in the shutdown procedure (in case some services take longer than others to clean up).

Most contact-closure UPSes will not power down the load if the line power is present. This can create a race when using secondary upsmon(8) systems. See the upsmon(8) man page for more information. The solution to this problem is to upgrade to a smart protocol UPS of some kind that allows detection and proper load cycling on command.


Charles Lepple

See Also

The core driver


The generic serial driver


The Qx driver

nutdrv_qx(8) (fuji subdriver)

Internet resources

The NUT (Network UPS Tools) home page:

Referenced By

nutupsdrv(8), upsd(8).

04/26/2022 Network UPS Tools 2.8.0 NUT Manual