In this article, we will discuss the types of UPS systems

An uninterruptible power supply (UPS) is equipment designed to provide power when the main power sources are disconnected.

In the operation of any server equipment a set of measures is used to protect it from various adverse effects: both network (viruses, hacker attacks, etc.), and physical (overheating, humidity, etc.). UPS for servers ensures full functionality during power failures.

In addition to the common tasks of the uninterruptible power supplies, the server UPS have additional functions. For example, remote control via LAN and the function of automatic UPS testing and automatic battery diagnostics.

Types of UPS of server equipment

Now, UPS for servers are available in three types:

• Standby (offline)
• With double conversion (online)
• Line-interactive

Standby devices are connected to an external network, and in case of power surges, there is a delay in switching to an autonomous power supply from the battery. This switching creates a power surge that causes malfunction of the devices connected to the device.

Disadvantages of standby UPS:

• Delays when switching to battery power — up from 5 ms
• Non-sinusoidal output voltage shape in offline mode
• Poor filtering and absence of mains signal correction
• Voltage fluctuations

Offline UPS system is not an optimal solution for protection of server equipment.

UPS with double conversion (online) are modern and most efficient. This equipment is most often used for powering servers and other devices. Batteries are active regardless of the operating mode of the network. At the output, it generates a pure sinusoidal stable voltage, ensuring uninterrupted power supply.

The design also includes a bypass, which allows quick switching from the main power source to the backup power source.

Line-interactive UPS are similar to the double-conversion equipment and have a transformer with switchable windings, which allows regulating the output voltage in case of various voltage spikes in the network without the participation of batteries.

UPS types by power connection:

• Single-phase UPSs. These devices can be connected to the network with a voltage of 220V, with a capacity of no more than 10 kVA. They are used to connect a single server, a group of servers or a separate server rack, as well as other telecommunication equipment.
• Three-phase UPS. The 380V equipment operates from a three-phase network with a voltage of more than 10 kVA and is characterized by high power and provides protection for server rooms, large IT complexes and data centers.

When connecting a single-phase UPS to a three-phase UPS, it is acceptable to use no more than 1/3 of the rated capacity of the device.

For example, a three-phase 15 kVA UPS can power 5 kVA on each phase, but a load of 7 kVA on one phase will cause the unit to crash.

There are models with a 3:1 configuration that can supply power to three phases with a 220V output, consuming a 380V mains voltage.

How to calculate the capacity of the UPS for the server equipment?

To determine the required power, it is necessary to summarize the metrics of all consumers connected to the device and in excess of this lay the reserve to compensate for possible operational overloads (recommended value — 30%).

In the technical documentation of IT equipment the maximum power of the power supply is specified, but not the actual power consumption of the device. It is recommended to ask the manufacturer for the actual power consumption of the load.

The specifications of the uninterruptible power supply indicate the output and input power factors:

• Input — reflects the impact of the UPS on the external mains and is not directly related to the connected load.
• Output — defines the maximum load in watts that the device is capable of supplying.

What backup time is required for server equipment?

UPS with built-in battery support at a load of 80% maintain power for 5-10 minutes, this interval is sufficient to save the necessary data. Note that the uptime decreases as the load increases.

For redundancy of powerful IT systems, we suggest using UPS systems with external battery modules. By increasing the number and capacity of the connected battery modules, autonomous operation can be extended to the required time.

Uninterruptible power supplies in off-line mode shut down automatically in stages, resulting in extension of redundancy of more critical equipment.

Purchase of external battery is recommended after consultation with a specialist, as in each individual case important factors must be taken into account: the load power, the quality of the external power grid, the type of charger, etc.

Additional functions of UPS

Uninterruptible power supplies have a wide range of functions and are equipped with various options.

• Cold start — starts from the battery in the absence of external voltage
• Automatic shutdown of powered equipment — sends a special signal to shut down the operating system and timely close all active applications. The signal is formed when the battery reaches a strong discharge
• Bypass is a feature that allows the maintenance of the device without interrupting the power supply to the load. There are automatic and mechanical bypass. The first is built into the device and triggers in case of overloads and failures, the second is implemented as an external module and is used in the manual operation
• Support of parallel operation — combines several UPSs of the same type, which increases the overall reliability and capacity of the system, in case of a failure of one power supply unit
• Hot replacement of batteries — replacement of battery units while in operation, without interruption of business processes
• Automatic testing of batteries — the device automatically monitors the technical condition, temperature and other characteristics of the batteries

It is important to pay attention to the input voltage range limit when choosing UPS systems.

PitON UPS systems are the perfect solution for server equipment

PitON offers a wide choice of single-phase UPS (from 1 to 20 kVA), suitable for protection of any server and network equipment.

Features:

• Wide input voltage threshold
• Input power factor correction
• USB-port and overvoltage protection ports;
• Automatic restart
• Built-in Smart-Slot;
• Cold start
• Built-in bypass
• Sound and LED indication
• High efficiency with 0,9 power factor
• Compatible with generators

PitON uninterruptible power supplies are produced with or without built-in batteries.

PitON double conversion UPSs are available in the standalone and rack-mounted versions. PT-Series models (1-3 kVA) are produced with the possibility of conversion to the vertical position and installation in a 19-inch rack.

If necessary, PitON UPSs are also available with firmware for special tasks, service bypass, increased battery charging current, galvanic isolation transformers, etc.

You can order PitON UPS equipment on our website or by calling us at 8-800-500-62-88.