to cause premature shutdowns of the UPS power, we strongly recommend, especially for voltage- signaling (dumb) UPSes, that you do most of the ini- tial testing with your computer plugged into the wall rather than your UPS. Thus if the UPS power is suddenly shut off, your computer will continue to run. We also recommend using safe-apccontrol as described below, until you are sure that the signaling is correct.

Also note that if you launch the execution of apcupsd while your voltage- signaling UPS is on battery power, it is very likely that your UPS will immediately shut off the power. This is due to the initialization of the serial port line signals, which often looks to the UPS like a shutdown command.

Finally, double-check the state of your cabling and UPS indicator lights frequently during testing. For voltage-signaling UPSes, apcupsd is not cur- rently able to detect whether or not the serial cable is connected. In ad- dition, some simple signaling UPSes with certain cable combinations are not able to detect the low battery condition. For more details please see Voltage Signalling Features Supported by Apcupsd for Various Cables.

Establishing Serial Port Connection

Once you have compiled, installed, and invoked apcupsd, you should wait to allow apcupsd to configure itself and establish contact with the UPS.

If you see the following message about 30 seconds after starting apcupsd:

apcupsd FATAL ERROR in apcserial.c at line 156 PANIC! Cannot communicate with UPS via serial port.

it means that apcupsd tried for about 30 seconds to establish contact with the UPS via the serial port, but was unable to do so. Before continuing, you must correct this problem. Some of the possible sources of the problem are:

•You have not configured the correct serial port name on the DEVICE directive in your apcupsd configuration file.

•The serial port that you have chosen has logins enabled. You must disable logins on that port, otherwise, the system prevents apcupsd from using it. Normally, the file /etc/inittab specifies the ports for which a getty process is started (on Sun machines, the serial port program equivalent to getty is called ttymon). You must disable this for the port that you wish to use.

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APC UPS control system manual Establishing Serial Port Connection
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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.
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