Installation: Serial-Line UPSes

Overview of Serial-Interface UPSes

If you have a UPS that communicates via serial port, you need to do two things before you can even think about configuring the software. First, you need to figure out whether it’s a dumb (voltage-signalling) UPS or speaks the apcsmart protocol (see this discussion (see upstypes)). Second, if you have an interface cable from APC, you need to figure out what kind it is. If you don’t have such a cable, you need to build one. A straight-through serial cable won’t work (see crazy).

According to Bill Marr the Belkin F5U109, also sold as F5U409 also works with apcupsd for kernel versions 2.4.25 or higher and kernels 2.6.1 and higher. These newer kernels are needed to have the patch that makes the mct u232 (Magic Control Technology) module and other adapters work with RS-232 devices that do not assert the CTS signal.

Connecting a Serial-Line UPS to a USB Port

By using a special adaptor, you can connect your serial-line UPS to a USB port. If you would like to free up your serial port and connect your existing serial port UPS to a USB port, it is possible if you have one of the later kernels. You simply get a serial to USB adapter that is supported by the kernel, plug it in and make one minor change to your apcupsd.conf file and away you go. (Kern adds: Thanks to Joe Acosta for pointing this out to me.)

The device that Joe Acosta and Kern are using is IOgear GUC232A USB 2 serial adapter. Bill Marr informs us that it also works with a Back-UPS Pro 650 and the 940-0095B cable.

At Kern’s site, running Red Hat 7.1 with kernel 2.4.9-12, he simply changed his /etc/apcupsd/apcupsd.conf configuration line to be:

DEVICE /dev/ttyUSB0

Depending on whether or not you have hotplug working, you may need to explicitly load the kernel modules usbserial and pl2303. In Kern’s case, this was not necessary.

135

Page 135 Page 137
Page 136
Image 136
APC UPS control system manual Connecting a Serial-Line UPS to a USB Port
Page 135 Page 137

UPS control system specifications

APC UPS (Uninterruptible Power Supply) control systems are vital components for ensuring uninterrupted power supply and protecting critical equipment from power interruptions, surges, or fluctuations. Designed by Schneider Electric, APC UPS systems are renowned for their high quality and reliability. They utilize advanced technologies and features to suit diverse applications, from home offices to large industrial settings.

One of the main features of APC UPS systems is the ability to provide backup power during outages. This is achieved through a battery system that activates immediately when the mains power fails. This seamless transition minimizes downtime and ensures that electronic devices continue to operate, protecting data integrity and equipment lifespan.

Another significant characteristic of APC UPS systems is their intelligent management capabilities. Most models come with PowerChute software, which provides users with real-time monitoring of power conditions and the status of the UPS. This software allows for graceful shutdowns of connected devices during extended outages, thereby preventing data loss and damage to devices.

APC UPS systems also incorporate advanced technologies such as Automatic Voltage Regulation (AVR). AVR technology ensures that the output voltage remains stable by correcting minor fluctuations without switching to battery mode. This not only prolongs the battery life but also provides a consistent power supply to the connected equipment.

Thermal management is another critical aspect of APC UPS control systems. The design often includes efficient cooling systems that prevent overheating, ensuring optimal performance and longevity of the unit. Some models feature EcoMode, which reduces energy consumption and lowers operational costs by working at high efficiency only when battery backup is not required.

APC UPS systems are designed with scalability in mind. Users can easily add more batteries or connect additional UPS units to accommodate growing power needs. Features such as hot-swappable batteries and modular design facilitate easy upgrades and servicing without interrupting power supply.

In terms of connectivity, APC UPS products often feature multiple options including USB, RS-232, and network management capabilities. This enables users to connect remote management tools and integrate the UPS with existing IT infrastructure.

In summary, APC UPS control systems deliver reliability, efficiency, and advanced technology features that cater to a wide array of power protection needs, making them a trusted choice for individuals and businesses alike.
Top Page Image Contents