UPS

An UPS: is shurt cut of Uninterruptible Power Supply.Itis a device or system that maintains a continuous supply of electric power to certain essential equipment that must not be shut down unexpectedly. The UPS is inserted between a primary power source, such as a commercial utility, and the primary power input of equipment to be protected, for the purpose of eliminating the effects of a temporary power outage and transient anomalies. They are generally associated with telecommunications equipment, computer systems, where even brief commercial power interruptions could cause injuries or fatalities, serious business disruption or data loss.

Home PCs are often at a greater degree of risk than PCs in a corporate environment for a number of reasons:

Household appliances - which can cause brownouts - are on the same system as valuable computer equipment. Rolling brownouts (utility's reaction to power crunch) are targeted at residential areas, so that they can maintain service to larger, corporate customers. Many insurance policies for home businesses do not cover data loss or computer services.

There are nine standard power problems that a UPS may encounter. They are as follows:

1. Power failure.
2. Power sag (undervoltage for up to a few seconds).
3. Power surge (overvoltage for up to a few seconds).
4. Brownout (long term undervoltage for minutes or days).
5. Long term overvoltage for minutes or days.
6. Line noise superimposed on the power waveform.
7. Frequency variation of the power waveform.
8. Switching transient (undervoltage or overvoltage for up to a few nanoseconds).
9. Harmonic multiples of power frequency superimposed on the power waveform

Standby

Standby uninterruptible power supplies run offline (meaning that the battery is not engaged until a power outage occurs), offering level 1 protection against power failures only. These are the least expensive variety of uninterruptible power supplies and are intended only for the home user. (offline UPS)

Line-interactive

In the Line Interactive UPS design, the battery-to-AC power converter (inverter) is always connected to the output of the UPS. Operating the inverter in reverse during times when the input AC power is normal provides battery charging.
When the input power fails, the transfer switch opens and the power flows from the battery to the UPS output. With the inverter always on and connected to the output, this design provides additional filtering and yields reduced switching transients when compared with the Standby UPS topology.
In addition, the Line Interactive design usually incorporates a tap-changing transformer. This adds voltage regulation by adjusting transformer taps as the input voltage varies. Voltage regulation is an important feature when low voltage conditions exist, otherwise the UPS would detect a power failure and switch to battery powered mode. Eventually the battery might become discharged and fail to power the load. Additionally, more frequent usage of the battery could reduce battery life or cause premature battery failure.
The ability to correct low or high line voltage conditions make this the dominant type of UPS in the 0.5 - 5 kVA power range.

Delta conversion online

Delta conversion is a type of Line interactive technology. In this configuration the primary power source is blended with power from the inverter. As the primary power varies away from its normal value the inverter comes to life to make up the difference. Unlike Off line technology no switch "ON" time is required. Unlike On-line technology no continuous separation of load and primary power is offered. Delta Conversion provides protection from all power anomalies except #7. Delta conversion is efficient, with system efficiency of up to 97% under nominal conditions when the inverter needs to do no work to correct deficiencies in the primary power. As the inverter does more work to correct deficiencies in the primary power the efficiency drops. At practical levels the efficiency of this technology can be less than that of On-line systems.

Double power conversion online

Double conversion online uninterruptible power supplies convert AC power to DC and then convert the DC back to AC to power the connected equipment. The batteries are directly connected to the DC level. This effectively filters out line noise and all other anomalies from the AC power for level 9 protection. An additional benefit of this technology is in the continuity: in all 9 problem conditions, the system remains in the same operating mode. Relative to other UPS topologies there are efficiency losses due to the double conversion of all of the power the load requires. Technological improvements have resulted in efficiencies of 94%, which gives this technology some advantages over other types that offer fewer modes of protection for the sake of 1 or 2% more in efficiency in some modes.

* UPS Dimensions and Weight(in inches) : Length, Width/Depth, Height and Weight.
* Software (on CD)
* Serial Port Cable
* Telephone Cord