Comparison Logicpower LPM-PSW-1500VA 12V 1500 VA vs Logicpower LPM-PSW-1500VA 1500 VA

— Standard (Tower). UPS designed for floor mounting or placement on any suitable horizontal surface. This “installation” is extremely simple, and it is suitable even for the most powerful and heaviest devices, and therefore most modern uninterruptible power supplies (of all categories) are made in the usual Tower form factor. They are supposed to be placed vertically.

— Rack. Models for installation in telecommunication racks. Most of these uninterruptible power supplies belong to the professional equipment segment, designed to power servers and other similar electronics (which are also often mounted in a similar way). The most common standard of racks is 19", however there are other options, so it would not hurt to check the compatibility of the UPS with a specific rack separately. We also note that models of this type are often equipped with legs that allow you to place the device on the floor “sideways” or in a vertical position. Display (if available) in such models may have a rotating design for ease of reading parameters in both positions.

— Wall-mounted. Uninterruptible power supplies, primarily designed for wall mounting. Wall hanging may be the best option in tight spaces. However, such an installation is not the only option - many devices can optionally be installed on the floor. Also note that wall-mounted UPSs are often used for heating boile...rs. The main disadvantage of this form factor is the need to drill into the walls to install an uninterruptible power supply.

- Flat. UPS, structurally assembled in a low, flat housing. As a rule, this form factor allows for several options for installing equipment: the uninterruptible power supply can be installed horizontally or vertically. However, it is the horizontal method of installing the UPS that predominates. In fact, everything depends on the location of the uninterruptible power supply and its dimensions - it would not hurt to clarify this point separately.

— Extension cord. Uninterruptible power supplies that resemble an extension cord in appearance. Structurally, such UPSs consist of a set of sockets in one housing, with the sockets located on the top platform of the uninterruptible power supply. Often, the housing of such UPSs is provided with holes or fasteners for wall mounting.

The time required to transfer the load from mains power to battery power. In standby and interactive UPSs (see Type), a short-term power failure occurs at this moment — accordingly, the shorter the time to switch to the battery, the more uniform the power supply is provided by the source during a power failure. Ideally, the switching time for the traditional 50 Hz AC frequency should be less than 5 ms (a quarter of one cycle of the sine wave). With inverter UPSs, the transfer time is, by definition, zero.

In this case, the input voltage range is implied, in which the UPS is able to supply a stable voltage to the load only due to its own regulators, without switching to the battery. For redundant UPSs (see "Type") this range is quite small, approximately 190 to 260 V; for interactive and especially inverter ones, it is much wider. Some UPS models allow you to manually set the input voltage range.

The maximum current drawn by the UPS. In fact, the current reaches its maximum value only when the UPS is operating from the mains with maximum load power and a completely discharged battery. However, when calculating the load on the power grid, this parameter should be taken into account.

This parameter characterizes the degree of difference between the AC voltage at the output of the UPS and the perfect voltage, the graph of which has the shape of a regular sinusoid. The perfect voltage is so named because it is the most uniform and creates the least unnecessary load on the connected devices. Thus, the distortion of the output voltage is one of the most important parameters that determine the quality of the power received by the load. A distortion level of 0% means that the UPS produces a perfect sine wave, up to 5% — slight sine wave distortion, up to 18% — strong distortion, from 18% to 40% — a trapezoidal signal, more than 40% — a square wave.

Rated voltage of external batteries that can be used in the UPS.

For more information about such batteries, see "External battery connection", here it is worth saying that the voltage of the external battery must correspond to the voltage for which the UPS is designed. If these parameters differ, at best, the UPS simply will not start, and at worst, overloads and even a fire are possible.

In general, the more powerful the UPS, the higher the voltage of the external batteries it is designed for. However, there is no strict rule. Some models even allow for multiple voltage options, such as 96/108/120 V. It is also worth noting that a power source with the required voltage can be assembled from several lower voltage batteries connected in series: for example, 3 batteries of 12 V can be used to achieve 36 V.

It is important to emphasize that the standard voltages for most modern UPS systems are multiples of 12 V. However, car batteries cannot be used in these devices. Despite having identical voltages, car batteries are designed for a fundamentally different mode of operation. Using them in a UPS can result in, at best, improper functioning of the device, and at worst, fires and even explosions.

The protection functions provided in the design of the UPS.

— Short circuit protection. A short circuit is a sharp drop in load resistance to critically low values, due to which the current strength increases and the UPS experiences significant overloads that can disable the device and even cause a fire. It may be caused by a problem with the connected device, poor insulation, foreign objects, etc. In the event of such a situation, the short circuit protection system turns off the UPS, preventing unpleasant consequences.

— Overload protection. Overload in this case is the excess of the load power consumption over the output power of the UPS. Working in this mode can also lead to unpleasant consequences up to breakage and fire; to avoid this, a protection system is installed that turns off the UPS when an overload occurs.

— Overcharging protection of external battery. The overcharge protection function prevents the accumulation of excess energy in the battery, from which the UPS operates in autonomous mode. Overcharging is highly undesirable for any type of battery. It can lead to various unpleasant consequences - from deterioration in performance to overheating and fire of the battery. The automatic protective equipment on board the uninterruptible power supply turns off the power after the battery is fully charged. This prevents “extra” curre...nt from entering the battery, which could damage it. This system is convenient in that the battery can be left on charge for a long time without fear of overexerting it.

— Noise filtering. A system that suppresses high-frequency interference in an electrical network — these can be either single voltage surges when turning on and off powerful electrical appliances, or long-term interference from constant sources, such as electric motors. These interferences can adversely affect the operation of electronics connected to the network (up to visible failures); the noise filtering system avoids this. Such systems are quite simple, and therefore most modern UPSs are equipped with them.

— Data line protection. High-frequency interference protection system, similar to interference filtering (see above) — only used not in an electrical network, but in a telephone or wired computer (LAN) network. Such networks are also subject to interference from various sources of electromagnetic radiation, which can cause failures of equipment connected to them: PCs, printers, fax machines, etc. UPSs with this feature have at least two LAN standard connectors (input and output), into which appropriate network or telephone (with RJ-11 connectors compatible with LAN) cables are inserted.

— Emergency cut-off. This connector allows you to connect the UPS to an emergency power off system. Thus, in an emergency (for example, in the event of a fire), the entire room, including and with a power reserve, can be completely de-energized by pressing one button. Without this, the UPS would simply switch to battery when the power goes out and leave the equipment energized, which could lead to disastrous consequences.

— Sound alarm. A system that gives an audible signal in various important situations. It is most commonly used to signal a power outage and the UPS is transferring to battery power. Without a sound signal, this could not be noticed at all (the light is not always on in the room, it goes out when the network fails, the contact in the socket itself may disappear, etc.), which is fraught with a sudden shutdown of the equipment, data loss and breakdowns. Also, sound alarm can be used for other events — low battery, end of charge, bypass on / off, etc.

Fuses are used to protect the UPS from a critical increase in current strength: at the right time, they open the circuit, preventing unpleasant consequences. Today, these types of fuses are used.

— Melting. At a critical current strength, the conductive element in such a fuse melts and opens the circuit. The fusible protection is disposable, after operation such a fuse must be replaced.

— Automatic. Such a fuse has a sensor that monitors the current strength and opens the contacts at the right time. Its main difference from fusible is reusability: after operation, the circuit can be closed again with literally one press of the button on the fuse.

Many modern UPSs can be connected to a computer or other special devices. This provides advanced options for monitoring the parameters of the UPS and managing its functions: without leaving the computer, you can monitor the battery status, network parameters, load, enable special modes, apply automatic adjustment, etc. Such a connection can be made according to the following standards:

— RS-232. It's a COM port. Initially designed to connect various peripherals to a computer. Today it is also quite widespread, however, due to its relatively large size, it is installed mainly on stationary PCs.

— USB. A universal port for connecting various peripherals to a computer, the most popular interface of this kind today — at least one USB port has an absolute majority of computers and laptops.

-LAN. A port used to connect to wired computer networks. Models with this interface can often be connected as a network device, which allows, if necessary, to control them from any computer on this network.

— SmartSlot. A slot in the UPS case for installing expansion cards (SmartSlot cards). The development of APC, is used mainly in the devices of its production. Such cards can provide a very diverse set of features: additional connection ports beyond the standard ones (for example, a LAN control port), a web managemen...t interface, support for SNMP, Secure HTTP and other protocols, connection of temperature / humidity sensors, and much more. To date, a wide range of cards is being produced, making it easy to choose a set of additional functions depending on the specific situation. Most UPS models have one SmartSlot, but if necessary, you can use a special expander and install two cards, and the largest models can have two slots as standard.

— "Dry contact". In uninterruptible power supplies, the term "dry contact" refers to a professional interface used to transfer data on the operation of the UPS to specialized external equipment. Such an interface usually has a whole set of contacts (on the order of 10), often in the form of terminals. And the scheme of its operation can be simply described as follows: when certain parameters are reached, the control relay closes or opens a given set of “dry contacts”, on the basis of which the control device receives information about one or another parameter of the UPS operation.