apcsmart-old - Man Page

Driver for American Power Conversion Smart Protocol UPS equipment

Synopsis

apcsmart-old -h

apcsmart-old -a UPS_NAME [OPTIONS]

Note

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

Supported Hardware

apcsmart-old should recognize all recent APC models that use a serial protocol at 2400 bps​. This is primarily the Smart-UPS, Matrix-UPS and Back-UPS Pro lines​.

The driver attempts to support every bell and whistle of the APC reporting interface, whether or not this is strictly sensible​.

Some older hardware may only report a handful of variables​. This is usually not a bug—they just don’t support anything else​.

Cabling

This driver expects to see a 940-0024C cable or a clone by default​. You can switch to the 940-0095B dual-mode cable support with the cable= definition described below​.

If your 940-0024C cable is broken or missing, use this diagram to build a clone:

https://www​.networkupstools​.org/cables/940-0024C​.jpg

Extra Arguments

This driver supports the following optional settings in the ups.conf(5):

cable=940-0095B

Configure the serial port for the APC 940-0095B dual-mode cable​.

sdtype=num

Use shutdown type num, according to this table:

0

soft shutdown or powerdown, depending on battery status

1

soft shutdown followed by powerdown

2

instant power off

3

power off with grace period

4

"force OB" hack method for CS 350

Modes 0 and 1 will power up the load when power returns​. Modes 2 and 3 will keep the load turned off when the power returns​.

Mode 4 exploits an oddity in the CS 350 models since they only seem to support the S command, but then only when running on battery​. As a result, the driver will force the UPS to go on battery if necessary before sending the shutdown command​. This ensures that the load gets reset​.

Bugs

Some older APC UPS models return bogus data in the status register during a front panel test​. This is usually detected and discarded, but some other unexpected values have occasionally slipped through​.

APC UPS models with both USB and serial ports require a power cycle when switching from USB communication to serial, and perhaps vice versa​.

Authors and History

Nigel Metheringham <Nigel​.Metheringham@Intechnology​.co​.uk> (drawing heavily on the original apcsmart driver by Russell Kroll)​.

This driver was called newapc for a time and was renamed in the 1​.5 series​.

In 2​.6​.2 the driver was renamed to apcsmart-old, being superseded by updated version with new features which currently holds the apcsmart name​.

See Also

The core driver

nutupsdrv(8)

Internet resources

The NUT (Network UPS Tools) home page: https://www​.networkupstools​.org/historic/v2​.8​.5/

Referenced By

nut(7), nutupsdrv(8), upsd(8).

08/25/2026 Network UPS Tools 2.8.5 NUT Manual