Energy Systems Analysis & Solutions
An important part of ensuring optimum performance of a system is through energy performance monitoring and verification.
Uninterruptible Power Supply (UPS) systems provide emergency or backup power to a load when the input power supply fails. It provides near-instantaneous protection from input power interruptions, generally through the use of batteries. A UPS has a relatively short runtime, but is usually sufficient to allow for proper shutdown of sensitive equipment, start-up of a more secure power supply, or for the issue to be resolved.
A UPS is generally used to protect data loss from sensitive communication devices, to ensure the reliability of critical equipment such as in hospitals, or to provide minimum power for equipment such as emergency lighting.
A UPS includes a battery, inverter and charging device (including rectifier). While mains power is connected, it is used to power connected equipment and connects to the battery charger. When an outage occurs, the UPS battery provides the power to the connected equipment through an inverter (converting the DC output of the battery to AC to power the equipment).
UPS systems can be connected to operate in three main ways:
1. Standby – the UPS is normally connected to the main power, and provides battery backup power should the supply voltage fall outside of the determined operating values. The UPS switches the connected equipment on to its DC-AC inverter output.
2. Line interactive – A line interactive UPS operates in a similar way to a standby UPS when power loss occurs. This type of UPS is able to tolerate continuous under and overvoltage conditions without switching to the battery supply by using an autotransformer to compensate for voltage dips and spikes.
3. Online – In an online UPS, the batteries are always connected to the inverter, so that no power transfer switches are necessary. When power loss occurs, the rectifier simply drops out of the circuit and the batteries keep the power steady and unchanged. When power is restored, the rectifier resumes carrying most of the load and begins charging the batteries. The online UPS is ideal for environments where electrical isolation is necessary or for equipment that is very sensitive to power fluctuations.
Figure: UPS system in standby mode
Captech partner with APC to provide reliable UPS solutions.
Our range of products suit a broad range of applications including hospitals, shopping centres and other areas where redundancy is required including for emergency and critical power requirements.