Input voltage range
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.
Input frequency
The operating frequency of the alternating current supplied to the input of the UPS — or more precisely, the frequency range of this current in which the device can supply the required power to the load due to its own regulators, without using a battery. When this range is exceeded, the UPS switches to battery mode. The smallest input voltage range is reserved for standby UPSs (see "Type"), the largest for inverter UPSs.
Output frequency
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.
Redundant sockets
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.
Battery type
- 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.
Full charge time
The time it takes to fully charge the UPS battery. Note that in this case, this time is calculated according to special rules: not from 0 to 100% of the charge, but from a state in which it is impossible to maintain half the load, up to 90% of the charge. Of course, a full charge will take a little longer. However, this data is closer to practice than the “from 0 to 100%” calculation: the inability to work at half load makes the UPS practically useless, and this condition can be taken as zero, and 90% of the battery is already able to provide a good guarantee in case of a power failure.
Control interfaces
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.Operating temperature
Ambient temperature range in which the UPS is guaranteed to maintain normal operation.
All modern "uninterruptible" without problems endure the temperatures typical for residential and office premises. Therefore, it makes sense to pay attention to this parameter if the device is planned to be used in more extreme conditions — for example, in an unheated room, or vice versa, in a production workshop with a high air temperature. At the same time, it's ok to take a margin for temperature: this will give a guarantee in case of unforeseen situations, besides, the wider the temperature range, the higher the overall resistance to adverse conditions.
