When exploring Standby Power and UPS System Specifications, it is important to determine whether your electrical supply is single-phase or three-phase. Small UPS systems typically operate on a single-phase input and output, while larger systems are designed for three-phase input and output. In the mid-range, UPS systems often feature a three-phase input and a single-phase output.
When considering UPS system specifications, not all critical loads require protection from a UPS. Only systems that cannot tolerate brief power outages, such as servers, need UPS protection to prevent significant damage and issues. On the other hand, critical systems that can withstand short power interruptions, like server room cooling systems, can be safeguarded by a generator. Server room cooling systems are considered critical loads as their failure can lead to thermal shutdown of the servers, protecting them from overheating.
The primary role of an online UPS is to regulate fluctuations in the main power supply, which typically occur for short durations. In the event of a complete power failure, the UPS system relies on its battery to maintain a steady flow of power and, when combined with a generator, ensures uninterrupted power until the generator takes over.
An online UPS provides uninterrupted electrical supply during a main power failure and seamlessly transitions back to the main power once the issue is resolved. It also features an automatic bypass to the main power in case of an overload or fault condition.
One type of UPS system is the On-line/Double Conversion Technology, which offers the highest level of power protection. This UPS converts incoming AC power from the main supply to DC power. The DC current powers the battery and the inverter, which then converts the DC back to AC, providing a regulated, clean, and conditioned AC output to the protected load.
The battery is always active, ensuring continuous power supply to the inverter in case of a main power failure. This results in uninterrupted power delivery to the protected load without any switching. The UPS also includes a static bypass circuit, which serves as a failsafe mechanism by supplying AC main power to the load in the event of an overload or internal fault.
Online UPS systems are typically recommended for use with generators due to their ability to tolerate voltage and frequency variations that may occur with generators. Additionally, battery pack extensions can be utilized to extend runtime.
An offline or standby UPS provides basic protection against issues with the main power supply. The AC main power passes through the UPS, which includes RFI filtering and limited spike protection.
During a main power failure or if the AC main voltage falls outside the UPS operating range, the inverter starts up, closes a relay, and provides power to the load. When the AC main power returns, the output switches back to the main power, and the inverter shuts down. There is a brief interruption during the transfer to and from the inverter. The output waveform when the inverter is active is usually a square wave or stepped sine wave.
Offline units typically have power ratings ranging from 250VA to 2kVA and offer limited communication capabilities. Although they are relatively affordable, they are generally recommended for single PCs, workstations, and home office applications.
A line-interactive UPS provides more protection than an offline UPS but does not offer complete protection against issues with the main power supply, unlike an on-line double conversion UPS system.
These UPSs operate similarly to offline UPSs but provide better spike protection. They also have a wider tolerance to voltage fluctuations due to a voltage-trimming transformer or a similar device. This device adjusts the incoming AC main voltage when it is too high or too low, preventing unnecessary battery power usage and preserving battery life. In case of a main power failure or if the incoming
For any questions you have, please contact us so we can help
Main Office:
Plas Trefilan,
Trefilan Talsarn,
Lampeter, SA48 8QZ
Address:
Powerhouse, Miners Ln,
Old Colwyn LL29 9HG
Colwyn Bay Tel: 01492551323
Cardiff Tel: 02920025354
Lampeter Tel: 01570940350
