Comparison Volt Polska Micro UPS 800 800 VA vs CyberPower UT850EG 850 VA

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.

The maximum output power supplied by the UPS, in other words, the highest apparent load power allowed for this model.

This indicator is measured in volt-amperes (the general meaning of this unit is the same as that of the watt, and different names are used to separate different types of power). The total power consumption of the load, implied in this case, is the sum of two powers — active and reactive. Active power is actually effective power (it is indicated in watts in the characteristics of electrical appliances). Reactive power is the power wasted by coils and capacitors in AC devices; with numerous coils and/or capacitors, this power can be a fairly significant part of the total energy consumption. Note that for simple tasks, you can use data on effective power (it is often given for UPS — see below); but for accurate electrical calculations it is worth using the full one.

The simplest selection rule for this indicator is: the maximum output power of the UPS in volt-amperes should be at least 1.7 times higher than the total load power in watts. There are also more detailed calculation formulas that take into account the characteristics of different types of load; they can be found in special sources. As for specific values, the most modest modern UPSs give out 700 – 1000 VA, or even less — this is enough to power a PC of average performance; and in the most "heavyweight" models, th...is figure can be 8 – 10 kVA and higher.

The effective output power of the UPS is, in fact, the maximum active power of the load that can be connected to the device.

Active power is consumed directly for the operation of the device; it is expressed in watts. In addition to it, most AC devices also consume reactive power, which is "wasted" (relatively speaking) is spent by coils and capacitors. Apparent power (denoted in volt-amperes) is precisely the sum of active and reactive power; it is this characteristic that should be used in accurate electrical calculations. See "Maximum output power" for details; here we note that when selecting a UPS for a relatively simple application, it is quite possible to use only effective power. This is at least easier than converting the watts claimed in the characteristics of the connected devices into full power volt-amps.

The most modest modern "uninterruptibles" give out less than 500 watts. 501 – 1000 W can be considered an average value, 1.1 – 2 kW is above average, and in the most powerful models this figure exceeds 2 kW and can reach very impressive values (up to 1000 kW or more in some industrial class UPS).

The number of outlets connected to the power reserve(battery) provided in the design of the UPS. In order for the UPS to fulfill its main role (providing a backup power in case of power outages), the corresponding electrical appliances must be connected to these outlets. The sockets have a standard shape and are compatible with the vast majority of popular 230 V plugs.

At a minimum, the UPS has 1 or 2 outlets and, in more advanced ones, there may be 3 or more.

A socket for a specific type of plug in the UPS design.

— Type F (Schuko). A traditional European socket with two round holes in the center and grounding contacts in the form of two metal brackets (at the top and bottom of the socket). The term Schuko stuck to this type of socket due to the abbreviation from the German Schutzkontakt - protective contact.

— Type E (French). The French style socket has two round holes and a protruding ground pin just above them in the center. The standard has become widespread in France, Poland and Belgium (along with the traditional type F sockets).

— Type G (British). The plug for such sockets consists of two flat horizontal pins and one flat vertical pin for grounding. The standard is found mainly in the countries of the United Kingdom, Malta, Cyprus, Singapore and Hong Kong.

— Type B (American). American-style sockets are designed for plugs with two flat prongs and a semicircular grounding contact. Type B is widely used in regions with voltage 110 - 127 V - USA, Japan, Saudi Arabia, etc.

The value of the operating voltage of one complete battery. In most cases, it is 12 V, UPS with 24-volt batteries is a little less common.

The type of battery installed in the UPS.

— Fiberglass (AGM). An advanced type of lead-acid battery with electrolyte in an adsorbed state: the compartments of such a battery are filled with porous material, which contains acid. At the same time, the battery case is sealed and AGM models are maintenance-free. This technology is the most popular in batteries for uninterruptible power supplies: it is ideal for batteries operating in buffer mode (that is, when they rarely need to be discharged and, as a rule, little by little). In addition, it provides a long service life, and AGM batteries are inexpensive. The disadvantages of this option include the impossibility of replenishing the electrolyte if it leaks, as well as poor tolerance to overcharging (although the latter becomes irrelevant with a high-quality power controller).

— Gel (GEL). A type of lead-acid battery that uses a gel electrolyte. GEL batteries are best suited for operation in cyclic mode - that is, when the battery needs to power the load for a long time, discharge almost to zero, then charge and again provide long-term autonomous power. But for the buffer mode, in which most UPSs operate (standing on standby for a long time in order to briefly maintain power supply in the event of a failure), this technology is not suitable for a number of reasons. Therefore, it makes sense to purchase such batteries only in cases where t...he “uninterruptible power supply” has to be turned on almost every day - for example, in unstable networks with constant and long-term power outages.

— Lithium-ion (Li-Ion). The key advantages of lithium-ion batteries are high capacity with small dimensions and weight. Also, Li-Ion batteries are not subject to the “memory effect” and can charge quite quickly. Of course, this option is not without its drawbacks - first of all, it is sensitive to low and high temperatures, and if overloaded, the lithium-ion battery can catch fire or even explode. However, thanks to the use of built-in controllers, the likelihood of such “emergency” situations is extremely low and, in general, the advantages of this technology significantly outweigh the disadvantages.

— Lithium iron phosphate (LiFePO4). An advanced modification of lithium-ion batteries (see above), designed to eliminate some of the shortcomings of the original technology. Lithium iron phosphate batteries are characterized by a large number of charge/discharge cycles, chemical and thermal stability, low temperature tolerance, short charging time (including high currents) and safety in operation. The likelihood of an “explosion” of a LiFePO4 battery when overloaded is reduced to almost zero, and in general, such batteries cope with high peak loads without problems and maintain the operating voltage almost until they are fully discharged.