Comparison Marsriva MR-UF800L 800 VA vs Marsriva MR-UF1200 1200 VA

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 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" mode...ls, this 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.

The number of USB A connectors provided in the UPS, designed to charge external devices, such as smartphones or tablets.

This number corresponds to the number of gadgets that can be simultaneously charged. True, it is worth considering that not every UPS with this function is able to charge USB devices from its own battery, without external power supply - it is better to check this possibility before buying.

- Lead acid. Structurally, lead-acid batteries are based on a combination of electrodes made of lead compounds immersed in a liquid electrolyte, the role of which is played by an aqueous solution of sulfuric acid. The advantages of this type are simplicity and low cost, low self-discharge, no "memory effect" and maintaining performance in a wide temperature range. At the same time, the less charge remains in such batteries, the less current they produce. Also, lead-acid batteries are afraid of deep discharges, take a long time to charge, have large dimensions and weight in the context of other types.

- Lead-acid (AGM). An advanced type of lead-acid battery with an electrolyte in a jelly-like state. The gel electrolyte provides maximum contact with the negative and positive plates while maintaining a uniform consistency throughout the volume. AGM batteries impress with their high reliability, low self-discharge, deep discharge resistance and long service life. However, they are sensitive to charge quality, short circuits and negative temperatures.

— Li-Ion. Lithium-ion batteries have a high capacity with small dimensions and weight. They are not subject to the “memory effect”, they are able to charge quite quickly, they can boast of an excellent reserve for charge-discharge cycles. Li-Ion batteries also have disadvantages - first of all, it is sensitivity to low or high temperatures, and when overloaded, such a battery can catch fire or even explode. Howeve...r, due to the use of embedded controllers, the likelihood of such "accidents" is extremely small and, in general, the advantages of this technology significantly outweigh the disadvantages.

The capacity of the battery installed in the UPS. For models with multiple batteries, this is both the total working capacity and the capacity of each individual battery: the batteries in such devices are usually connected in series, so that their total capacity corresponds to the capacity of each individual cell.

Theoretically, a higher battery capacity means the ability to power loads of a given capacity for longer. However, in fact, this parameter is more of a reference than practically significant. The fact is that the actual amount of energy stored by the battery depends not only on the capacity in amp-hours, but also on the voltage in volts; this voltage is often not specified in the characteristics, despite the fact that for accurate calculations it must be known. So when choosing, you should focus on more "close to life" characteristics — first of all, on the directly claimed operating time in different modes (see above).

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 number of batteries supplied with the UPS.

In general, this parameter is more of a reference than practically significant: the number of batteries is selected in such a way as to provide the desired performance — primarily the time of continuous operation. First of all, it is worth paying attention to such characteristics when choosing.