Comparison KSTAR UA150 1500 VA vs Powercom RPT-1500AP Schuko 1500 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.

Bypass(by-pass) means such a mode of operation of the UPS, in which power is supplied to the load directly from an external source — the mains, diesel generator, etc. — practically without processing in the UPS itself. This mode can be activated either automatically or manually.

— The automatic bypass is a kind of safety measure. It turns on when the UPS in normal mode cannot supply power to the load — for example, when the UPS is overloaded due to a sharp increase in the power consumption of the load.

— Manual bypass allows you to enable this mode at the request of the user, regardless of the operating parameters. This may be necessary, for example, to hot-swap a battery (see below for details) or to start equipment that has a starting capacity greater than that of the UPS. Technically, it can also play the role of a security measure, but automatic systems are more reliable in this sense.

Some UPSs provide both options for enabling the bypass.

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.

The frequency (frequency range) of the AC voltage output by the UPS. For computer technology, the frequency range of 47-53 Hz is considered normal, although the smaller the deviation from the 50 Hz standard, the better. On the other hand, in some UPS models, this frequency can be automatically synchronized with the frequency of the mains — so the power supplied to the load will not differ regardless of whether the load is powered by the mains or from the battery. In this case, a wider frequency range, on the contrary, is more desirable.

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 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 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.