UPS or Inverter? 

How To Choose Your UPS or Inverter for Best Results!

UPS definition: Uninterruptible Power Supply

This is your power back-up and is generally used to ensure that there

is absolutely no interruption of power to your equipment, despite power-failures,

power surges, power sags or spikes. With the correct power back up your equipment

will continue functioning without an interruption - as if nothing had occurred.

The UPS

• A UPS consists of an Inverter, Transformer, Voltage regulator, Charger and Batteries.
  
• UPS sizes range from 500VA to 240 KVA.
  
• Transformer based UPS’s are more robust serving as power back ups on heavier equipment and machinery.

Transformer based UPS's have proved more reliable under severe conditions such as where: power outages are extended for longer periods of time, power cuts are a more regular occurrence and in areas where more power spikes or surges are experienced.

The INVERTER

• An inverter is the subassembly of a UPS that converts DC power to AC power electronically.
• The inverter is the device that changes DC (12v, 24v or 32v etc.) from a battery to 220VAC.
  
• It regulates the output constantly even while the battery is discharging - ensuring a stable 220VAC supply - smoothing out any small irregularities that may cause voltage fluctuations.

When calculating the battery size for your requirements the inverter allowance is included in the calculation. These units draw very little power from the battery and are generally quite reliable if not overloaded.

This smaller type UPS is used for general office and home equipment, which do not need to convert large quantities of power for extended periods of time and therefore use different technology in the design. This high frequency UPS converter-unit is designed to be more cost effective and excludes the use of a large expensive transformer to convert power.

A High Frequency conversion and 'line interactive' technology is used for power backups, and are often referred to as ‘INVERTERS’ (which still includes the inverter, charging circuit and battery) rather than a UPS.
Running an Inverter-UPS is a very cost effective means to standby power.

INVERTERS are used in general office and household equipment that draw less current and need to stay running for a shorter period of time, reducing the costs of a UPS with satisfying results. For specific usages see UPS Power SOLUTIONS

Types of UPS

Various operating methods have been employed for contrasting requirements allowing the UPS to be engineered according to individual needs. Depending on the quality of power and period of back up time required will determine what type of UPS should be used.                        

There are three basic circuits used each with its own advantages.
Namely: On-Line, Off-Line and Interactive.

On-Line UPS

The On-Line UPS is a contiuos pure Sinewave power supply which is the same as provided by mains. This double conversion UPS, operating under normal conditions, supplies clean smooth AC power after rectification.
Only when the UPS is overheating, overloaded, or out of order will the unit switching to bypass mode.

Usage:
Having a smooth change over this UPS is ideal for:

• Intermediate connection for Generator back up. 

• Equipment using motors

Off-Line UPS

The Off-Line UPS will only supply power when there is a power failure

Usage:
Change over has very little effect on the following equipment.

• Fans
• Lamps
• Small Frigdes
• TV, Video player, Radio etc...
  

Line Interactive UPS

The Line Interactive UPS supplies power from the bypass through its own transformer and the transformer is part of the charging circuit. When there is a power failure the transformer will transfer battery power to AC output

Usage:
A milli-second break in change over is normally insignificant to effect most processor driven equipment.

• Computers
• Servers

NEED TO KNOWS -

UPS BATTERIES

A 'Deep Cycle' battery is always recommended for UPS back up - Allows for large quantities of current to be drawn for long periods of time ie. Will deliver a continuos flow of current until flat without damaging internal plates

The battery size, is measured in AH (Ampere Hours), will depend on:

• a) How much power is needed to operate the equipment effectively and 

• b) How much back up time is required for the equipment to continue operating.

To calculate See: Battery Calculator 

Things of note when purchasing your UPS

1. Consider your requirements of power quality
   
2. Review the UPS specifications for high efficiency and low noise
3. Calculate the current capacity needed and consider future expansion
4. Reputed brands and manufactures for reliability
5. Choose the UPS based on your requirements
   

SEE OUR SPECIALS from  PowerbackUPS and order your UPS's online click here   

www.powerbackups.co.za