JSC "ISTOK" has been working in the market for the creation of means of generating current since 1959, the potential accumulated over the years allows us to offer our customers a wide range of autonomous or backup power supply for objects. Standard solutions which would suit everyone is not present, and our experts will draw up a project specifically for your object, saving your money.

We are interested in long-term, productive and fruitful cooperation. Contact our company. We are always ready for mutually beneficial work!

Autonomous and backup power

The fact of the alarming state of affairs in the Russian energy industry is recognized at the very high level. Frequent accidents on power lines, chronic lack of capacity, outdated equipment in moral and physical terms, constantly remind of themselves with unscheduled power outages.

As it spreads electrical appliances and machines, the need to use redundant power supplies is becoming more and more urgent. Climate change leads to more natural disasters causing power outages. Disruption of power supply can lead to economic and production damage, as well as create a risk to the life and health of citizens. Redundant power supplies are used to prevent or minimize damage of this nature.

Existing problems in the energy industry highlight the installation of independent power sources. An autonomous power plant plays the role of a reserve source of power supply, providing the opportunity to protect the consumer to the maximum extent from an emergency shutdown of power supply.
Power outages often occur in a country house: who among us has not spent the evening with a candle, in unusual silence without a TV? How to solve such a problem? Many diligent owners of dachas and country houses they acquire various generators for autonomous power supply, as a rule, diesel or gasoline mini-power plants.

However, what is clear to private owners is not always clear to those who were appointed as the owner by order from above, that is, the heads of objects of increased importance. It is noteworthy that, according to the results of inspections by Rostekhnadzor, in almost all regions of the center of Russia, more than 50% of socially significant facilities do not have emergency power. For example, in the Moscow region, only 60 objects out of 148 have their own microturbines or other autonomous power sources.
The statistics are sad and require decisive action. There is a corresponding decree, according to which all objects of high importance must have autonomous sources of electricity.

Let's look at what requirements are attached to autonomous power supplies for objects of increased importance.
Since an autonomous power plant comes into operation when the current supply from the main source is interrupted, automation plays a significant role. This is the ability of a backup generator to automatically start and stop when power is turned off or restored, as well as when certain parameters fall. In addition, an autonomous power source should automatically replenish fuel and lubricants and have a host of other useful features.

This reasonable requirement is often ignored when installing mini-power plants at high-value facilities. In many cases, they are activated after the start button is pressed. It is hard to imagine the consequences of a ten-minute power outage in the operation of hospital life support systems or operating room equipment.

The required capacity of the backup power supply must be determined during the design and construction phase, and the electrical wiring must be carried out at the same time. It all depends on what electrical devices you want to connect to a backup power source.

No less important requirements are the reliability and efficiency of an autonomous source. Moreover, the most important is the reliable operation of an autonomous power plant. This is what should be in the foreground in the process of its selection.

High-capacity storage uninterruptible power supply

Uninterruptible power supply systems (UPS Systems) are very popular in Russia today. If autonomous power plants are most often used during long power outages, then an uninterruptible power supply (UPS) is the most efficient and, importantly, economical way to provide Vacation home electricity during short-term, but frequent power outages. It is this circumstance that makes them an indispensable attribute of modern suburban housing.

Uninterruptible power supplies use the energy of batteries (batteries) to maintain the voltage in the network. In the presence of a UPS, electrical appliances that are in the house at the time of a power outage are transferred to the consumption of electricity accumulated by the batteries.

Such a system is indispensable for a computer, since an unexpected power outage can lead to loss of important documents, or, say, a refrigerator, if unexpected surprises happen on hot days. In addition, many country houses are equipped with systems autonomous heating, as well as water supply, which work only in the presence of electricity.

Compared to autonomous power plants, uninterruptible power supply systems have a lot of advantages. First of all, they are considered much more reliable (their service life exceeds 10–20 years) and do not require operating costs, unlike, say, diesel, gasoline or gas power generators. In addition, an uninterruptible power supply does not burden its owner with the need for periodic maintenance, with the exception of replacing batteries, the service life of which is 3–10 years, depending on the type of battery and operating mode.

The disadvantage of uninterruptible power supply systems can be called limited resources. In other words, if the voltage in the power grid often disappears for more than a few hours, then it is best to think about purchasing an autonomous power plant.

The prospect of protecting yourself from power outages by purchasing an uninterruptible power supply can be easily illustrated in numbers. So, in just 5 years of operation, the UPS allows you to save up to 6 times in comparison with a gas generator with automatic start. For the purity of the calculations, we assume that the voltage disappears once a week for 10 hours. As a result, the use of an uninterruptible power system is not only cheaper, but also associated with less hassle.

Power Supply Comparison:

UPS		Petrol generator
Item of expenses	Costs, rub.	Item of expenses	Costs, rub.
DPK-1/1-1-220M	13 000	Gasoline generator with ATS GESAN G5000H	55 000
Battery (12 V, 100 Ah) - 3 pcs.	21 000	Fuel	93 600
		Motor oil	3 150
		Filter replacement	7 700
		Replacing spark plugs	500
		Engine overhaul	20 400
Total:	34 000	Total:	180 350

Our specialists carry out the installation of equipment, before carrying out the work, we carry out the design of an uninterruptible power supply system, during which we try to take into account all the wishes of customers.

Despite limited resources, an uninterruptible power supply can freely provide electricity to a large cottage. Moreover, as a result of its operation, an unexpected loss of voltage in the network will not affect the operation of the autonomous heating system in any way ( gas boiler), water supply, refrigerator, fire and security systems, as well as all lamps and appliances connected to the mains.

At the same time, however, in the event of a power failure, it is better to refrain from using powerful electrical equipment. So, you can transfer the wash to the next day, as well as temporarily refuse to use dishwasher, as well as an iron. However, it is best before you buy an uninterruptible power supply, clearly calculate ultimate load and hence the demand for electricity.

In addition, it is possible to design the power supply system at home in such a way that power is supplied to powerful consumers bypassing the UPS, for example, directly to the power supply network or through gas generator with automatic start system. Thus, consumers who are sensitive even to short-term power outages (computers, home electronics, lighting, gas or diesel boilers, refrigerators) will be reliably protected. And consumers who tolerate power outages will be powered in a few seconds using an autonomous power plant with an automatic start system.

The amount of time a UPS can provide power to a home will depend on the power of the load and the capacity of the batteries. Interestingly, although the factors are closely related to each other, there is no linear relationship between them. In other words, if the load suddenly increases by 2 times, this does not mean that the uninterruptible power supply will last half as long.

To calculate the backup time, many parameters must be taken into account, in particular, the efficiency of a particular UPS, temperature environment, the condition of the batteries and the degree of wear of the batteries. You can calculate the approximate time in the case of using batteries of one capacity or another.

So, at a voltage of 36 V in the DC circuit, the UPS usually installs 3 batteries with a voltage of 12 V each. In this case, if, for example, the battery capacity reaches 100 Ah, and the load power is 100 W, then the system will work for 29 hours.

Load power, W	100	200	300	400	500	600	700
Battery capacity, Ah
18	4,6	1,9	1,2	0,8	0,6	0,4	0,3
27	7,8	3,2	1,9	1,4	1,1	0,8	0,6
42	12	5,8	3,4	2,4	1,8	1,4	1,2
70	20	10	6,7	4,5	3,4	2,7	2,3
100	29	15	10	7,3	5,4	4,1	3,5

At 96 V DC, the UPS will need to install 8 batteries of 12 V each. However, the reserve time in this case also increases significantly.

Load power, W	200	300	400	500	600	700	800	900	1000	1100	1200	1300	1400
Battery capacity, Ah
18	7,4	4,3	3	2,3	1,8	1,5	1,3	1,2	0,9	0,8	0,7	0,6	0,5
27	11	7,4	5	3,8	3	2,5	2,1	1,8	1,5	1,4	1,3	1,2	1,1
42	16,5	11	8,7	6,9	5,3	4,3	3,6	3,1	2,8	2,5	2,2	2	1,8
70	27	18	14	11	9,7	8,3	7,2	6,3	5,3	4,6	4,1	3,8	3,5
100	39	26	19,2	15,4	13,5	12	11	9,3	8,3	7,5	6,8	6,1	5,5

If the lack of electricity is caused by a periodic voltage deviation, then you can use a stabilizer. These devices convert electricity supplied with large voltage fluctuations.

In the event of a complete failure in the supply of electricity, voltage stabilizers are useless. On the other hand, their use as part of an uninterruptible power supply system allows you to reduce the load on the UPS, that is, to use it only when the mains power is completely lost.

However, when choosing battery capacity, do not forget that the pursuit of maximum values ​​\u200b\u200bmay be useless, since the capabilities of an uninterruptible power supply are limited by the current limit of the charger. However, it can be increased by installing additional charging boards.

In any case, in order to buy a UPS that would best meet current needs, it is preferable to seek help from specialists. Installing the system yourself is quite risky, since the slightest mistake can lead to undesirable consequences and costly equipment repairs.

In connection with frequent power outages, unstable voltage and frequency in the power grid, questions have recently arisen more and more often: How to provide yourself with electricity during a power outage? What source of autonomous power to choose? And how to do it?

First you need to decide on the conditions of the problem.

The first condition is load power consumption. This power is the sum of the capacities of individual electricity consumers. The number of consumers whose capacities add up to the total load power will depend only on your desire. However, it should be borne in mind that those consumers that you did not include in this list must be turned off while the autonomous power supply is operating. Failure to do so may result in overloading and even damage to the equipment.

That is, you need to understand what you want to receive? Ensure a comfortable existence for the duration of the outage, regardless of how long the network is disconnected, or get by with several especially important consumers, the disconnection of which can lead to serious material costs (for example, the heating system).

A country house, as a rule, consumes from 5 to 40 kVA. This includes lighting, heating systems, water supply, sewerage, household electrical appliances, security and fire alarm systems, video surveillance systems.

If you decide to power some of the consumers from an autonomous source (which is advisable from the point of view of price), then from this entire list you need to select, first of all, the most critical consumers for power failure (emergency lighting, heating system), and then summarize them less critical loads. Consumers of electricity that do not have an inductive component of power are called active: incandescent lamps, heaters. However, a simple summation of capacities will be fair until you get to equipment that has inrush currents. It tends to consume several times the rated current at the time of start. These currents must be taken into account and given an appropriate power margin (approximately 2.5-3.5 times). Such consumers are called inductive: electric drills, electric saws, pumps, compressors, refrigerators, laser printers, etc. In addition, it is necessary to take into account the coefficient of simultaneity, which shows the percentage of simultaneous operation of the equipment.

Prime Rating Power- this is the maximum power that the DGU can develop during continuous operation on a variable load for an unlimited time. The average load value in a 24-hour period is 70%, unless otherwise specified by the manufacturer. An overload of 1 hour for 12 hours of operation is not specified by ISO, but is allowed. The minimum load of the DGU is 25% of the PRP capacity.

That is, if you assume that your generator set will operate as the main source of electricity, then you need to focus on this particular power. If the PRP value is not specified, then this generator set can only operate as a standby power source.

Auxiliary and standby power (Emergency Standby Power)- This maximum, which DSU can develop when working on variable load during a possible power outage, which the DGU reserves, with an annual operating time of not more than 500 hours. Average power over a 24-hour period is 70% unless otherwise stated by the manufacturer. Overloading is not allowed.

The minimum load value of the DGS is not regulated, but is 25% of the PRP capacity.

That is, this is the power that the generator set can develop for a short time, as a backup power source. The ESP power is always greater than the PRP power, since this is the power that the generator set develops for a short time (no more than 500 hours per year), but overloads are not allowed.

Thus, the calculation of power consumption is not as simple as it seems at first glance, the task. And we recommend that you contact specialists for a correct and correct assessment of power consumption and an error-free selection of equipment.

Next important component the conditions for this task is battery life, that is, the time that your autonomous power source will work until the voltage of the main power supply is restored and enters the acceptable limits.

To determine this parameter, you need to analyze how often and how long power outages occur and, based on this, determine the battery life you need.

Let me explain why this is important. In case of short-term power outages with a small frequency, one of the options for solving the problem of autonomous power supply is to install an uninterruptible power supply that, in autonomous operation, uses the energy of batteries, the number of which can be increased depending on the required battery life (up to several tens of minutes). For longer and more frequent outages, an option to solve the same problem is to install a generator set, which also needs to provide an adequate supply of fuel depending on the required runtime.

And one more point must be taken into account when setting the conditions for this task - this is the presence of equipment that is critical to various kinds of jumps, impulses, voltage drops and frequency deviations of the main power supply. These are electronic control units for equipment (for example, a heating system boiler), computers, security and fire alarm controllers, plasma panels etc. That is, equipment that requires precisely high-quality power supply, otherwise it may not work correctly or simply fail.

Now that the conditions of the problem are known, we can begin to solve it. There are several options for technical solutions.

UPS according to the principle of operation can be divided into two groups: off line and on line. Off Line (Stand By) type of UPS that allows a load power interruption during the transfer from the input network to the inverter (transfer time, or transfer time). on line type of UPS that provides uninterrupted and filtered power to the load. By definition, on-line UPSs have zero transfer time; the load never sees a power interruption.

As a rule, for use as a backup power source for country houses, single-phase UPSs with a power of 4 to 10 kVA of the On Line class are used.

Compared to standby generator sets, UPSs have a number of undeniable advantages

• significantly higher reliability factor;
• big time time to failure;
• high quality output electricity;
• no need for periodic maintenance and replacement of consumables;
• noiselessness of work;
• ease of connection and installation.

However, in order to provide a relatively long autonomy time (from several tens of minutes to several hours), the UPS must be equipped with a sufficient number of batteries (hereinafter referred to as batteries) of a certain capacity, which will most often be limited by the technical capabilities of the UPS, namely the capabilities of the battery charger. In addition, the battery life will depend on several other parameters: the degree of load of the UPS, the efficiency of a particular inverter, the ambient temperature, the condition and degree of wear of the battery.

Of course, it is possible to create a powerful uninterruptible power supply system with a long autonomy. But this raises the question of the economic feasibility of such a decision, and this is an important factor in the process of choosing an autonomous power source.

Currently, there are a lot of different types of generator sets on the Russian market, a wide range of capacities from many manufacturers, various options the execution of which will make even the most sophisticated buyer think.

Below we give a classification according to the main features of the design of generating sets. And we will give brief explanations, so to speak, at the household level for each of the classification points.

By type of execution

• portable - household, semi-professional and professional gasoline or diesel generator sets up to 12 kVA, can be used as backup power sources; for the nutrition of consumers with medium and high intensity; to implement individual activities. They have an air cooling system, can be with an upper or lower arrangement of valves of the gas distribution system, are reliable, convenient and unpretentious in operation.
• stationary - professional diesel power plants with a capacity of 10 to 2500 kVA, are used as the main and backup power supplies. They have a liquid cooling system, as a rule, with an overhead gas distribution system valves, excellent resource indicators, low operating costs. Requires professional installation.

According to the cooling method

• air-cooled - generator sets that are cooled by ambient air.
• water-cooled - generator sets that are cooled by liquid (usually glycol mixtures with water).

By fuel used

• gasoline generator sets that use gasoline as fuel.
• diesel - generating sets in which diesel fuel is used as fuel.

By engine speed

• 3000 rpm - engines operating at this frequency are cheaper and smaller, but much noisier, with higher fuel and oil consumption and have a shorter resource;
• 1500 rpm - these engines are quieter, with lower consumption and longer life. Can be used as the main power source.

Type of alternator

• with a synchronous generator, have a higher quality of electricity, are able to withstand short-term overloads;
• with an asynchronous generator, structurally simpler and cheaper. However, they have a rather low quality of electricity at the output, and are not capable of overloading.

By number of phases

• single-phase (220 V 50 Hz), only single-phase consumers can be powered from such a generator set;
• three-phase (380 V, 220 V 50 Hz) from such a generator set can be powered by both three-phase consumers and single-phase. However, it must be borne in mind that the power of one phase of a three-phase station is 3 times less than the total power of the installation. It is also necessary to ensure the uniform loading of the phases in order to avoid the so-called “skew” of the phases, which adversely affects the condition of the generator set.

According to the location of the valves of the gas distribution system

• with the lower arrangement of valves;
• with overhead valves.

By launch method

• manual - used only for small portable stations, starting is done using a cord by spinning the engine crankshaft to the desired frequency to start;
• electric starter - used for all installations, starting occurs with the help of an electric starter by turning the ignition key;
• automatic - used for installations that have an automatic start function. Requires availability additional equipment. It is not necessary that a person be present when starting and accepting the load.

Now consider the main types of generator sets in the complex.

Gensets with 2-stroke or 4-stroke gasoline engine

• 2-stroke engines, as a rule, are put only on the most low-power and compact generator sets (mean time between failures is not more than 500 hours);
• 4-stroke gasoline engines are installed at more serious stations, but not more than 15 kVA (there is no more powerful gasoline engines). MTBF from 1000 to 4000 hours. The main manufacturers are the American company Briggs and the Japanese Honda.

Generator sets with 4-stroke diesel engine.

Air-cooled diesel generators are intermediate between gasoline and liquid-cooled diesel engines. Air-cooled diesel generator sets up to 6 kVA are not much different from their gasoline counterparts, although they have a longer resource and are more reliable. MTBF over 4000 hours. The main manufacturer is the Japanese company Yanmar.

More powerful air-cooled diesel engines up to 20 kVA are capricious in terms of fuel quality, quite noisy and bulky. So in this case it is better to look for an alternative among liquid-cooled diesel engines. The main manufacturer is the German company Hatz.

Liquid-cooled diesel engines are the most reliable and durable. MTBF up to 20,000 hours. They are industrial grade.

The most acceptable in terms of equipment with various options. Main manufacturers from 6 to 20 kVA:

1. Mitsubishi, 20 to 275 - John Deere, 200 to 500 kVA
2. Volvo and Perkins, over 500 kVA - MTU.

Now let's summarize this solution. With frequent and long power outages or in the absence of an external network, the choice is obvious. However, if we return to the third condition of the problem about consumers critical to power outages and quality of electricity, we see that this solution is unacceptable, since from the moment the voltage is lost until the moment it is restored, there is a break in the power supply through the generator set and the generator set does not protect against various kinds input network distortion.

In order to provide uninterrupted power supply to consumers critical to the quality of electricity and at the same time have a sufficiently long autonomy, we recommend using the combined operation of the UPS and the GU. In the event of a mains power failure, the UPS powers the batteries of the most critical consumers. The remaining consumers remain de-energized until the generator set is started. After starting the GU, the UPS goes into normal operation and charges the battery. This is the most acceptable option in terms of reliability.

However, when the UPS and GU work together, it must be borne in mind that when calculating the power of the GU, the UPS power calculated earlier must be summed up with the powers of other electricity consumers, taking into account the safety factor (1.3-2, depending on which rectifier the UPS and whether there are THD filters), taking into account the harmonic distortion of the UPS itself. So, as we see, the solution to the problem backup power supply is a rather complex and multifaceted task that requires serious study. This takes into account many factors related to both the load itself and the equipment. We recommend that when solving problems of this kind, in order to avoid making mistakes and to save your time, consult with specialists.

- you should know!

Subject " Backup and Autonomous Power Supply - you should know this!

To begin with, let's clarify the concepts of backup and autonomous power supply. So, backup power means an auxiliary source of electricity, which, in the event of a main line failure, should provide further power supply to power electrical consumers. They may not only be completely independent systems power supplies (batteries and converters powered by them, ministations, fuel cells etc.), but also emergency lines of urban power supply.

Autonomous power supply by itself means a completely separated power supply system that is capable of generating or distributing stored electrical energy to various consumers. In the event of a power failure in the main city power grid, such a system should take over the power load of existing consumers. Although, chemical power sources (including rechargeable batteries). The main idea of ​​this type of electrical source is to supply electricity to the load, provided there is no external source power supply (normal city power supply).

For the most part, these two concepts strongly intersect with each other, which gives reason to consider them one and the same (only in some cases can these terms be used “amazingly”). The problem of independent power supply can be solved in various ways, or rather, an autonomous power supply system can be made based on various ways production of electrical energy. The beauty of electricity is that this force, invisible to the human eye, is universal. Only the ways of converting one type of energy into another differ.

Where is the term backup power mainly used? Where there is a high probability of disconnection of the main source of power supply (which is usually the city power grid), or in the case when blackouts occur extremely rarely, but the phenomenon of “blackout” itself is quite critical. In these cases, the main task of the backup power supply is to timely pick up the existing load and then provide electricity to the existing consumer until the main supply from the city network is fully restored.

You can hear more about autonomous power supply when it comes to the complete absence of the main source of power supply (city power grid). In this case, this most autonomous power supply acts as the main power supply system (or it is used so often that it reserves the right to be called such). Such cases include the implementation of power supply country house(where there are temporary or permanent problems with the supply of the city power grid), places remote from the city (where the city highway was not originally provided), etc.

The role of the main power supply system is a complex energy network, the main node for generating electricity in which is a nuclear power plant, thermal power plant, hydroelectric power plant. In the case of autonomous power supply, the power generation center is mini power generating systems that operate on combustible fuels (gasoline, diesel, gas, coal, etc.), wind energy (windmills), solar ( solar panels), chemical reactions (chemical current sources - batteries, accumulators, fuel cells).

The specific use of a particular source of electricity generation depends on the existing conditions (area, climate, modes of operation of autonomous sources, need, cost, etc.). It is worth adding that additional parallel power lines, which are powered by the same city power networks, can act as a backup power source.

The energy crisis, which was the result of the Moscow accident at the Chagin substation and overtook Moscow and a number of regions adjacent to it, showed that for our person, even such extraordinary events are not at all a reason to be nervous.

For the Ministry of Industry and Energy of the Russian Federation, the power outage that occurred in Moscow and neighboring regions of Russia is a unique emergency situation, however, chronic outages of both individual houses and entire neighborhoods in various regions of the country do not happen so rarely.

Employees of the Ministry of Industry and Energy of the Russian Federation, of course, have drawn the appropriate conclusions and are already reporting to us that “an invaluable positive experience will be learned from the entire range of actions related to the elimination of power outages,” however, worn-out equipment that has been in service for 40-50 years, cannot be replaced overnight, and while the technical re-equipment of the electric power industry is underway, we can also do something to at least somehow protect ourselves from such costs of civilization.

Uninterruptible power supplies

as you know, uninterruptible power supplies (UPS or UPS - Uninteruptable Power Source) are designed more to prevent the device from crashing, and not at all for long-term operation of it in the absence of mains voltage. Actually, the cost of batteries is the most significant share in the total cost of the UPS, and the larger the capacity they have, the more expensive the system.

Strictly speaking, those figures that are indicated in the price lists or on the UPS cases indicate the so-called apparent power, which is measured in volt-amperes (VA, V A) and is applicable to direct current, or active power, measured in watts (W) and battery life is non-linear with UPS power.

For switching power supplies for computers, power in volt-amperes corresponds to power in watts with a coefficient of 0.6-0.8, that is, if 400 V A is indicated on the UPS, then this corresponds to a total power of connected devices of about 280 W. However, manufacturers recommend choosing a UPS with a 20% headroom in terms of load power, so that the user still has enough time to complete all the final steps before turning off the computer. For example, for modern desktop PCs with 300W power supplies, you should choose a 350-360W (or 514VA) UPS.

Experience shows that a simple home computer with a monitor runs on a 400 V·A UPS for only 5-10 minutes at best. Therefore, according to existing models and load power margin, it is better to choose a UPS rated for 600-750 V·A. Moreover, if for a UPS with a power of 500 V A the operating time is 10-15 minutes, then for a UPS with a power of 1000 V A the same set of devices will work for 40 minutes (that is, one powerful UPS works longer than two with the same total power) . By the way, if the UPS overload lasts at least a couple of seconds, it will simply turn off the entire load.

However, the cost of the IPB depends on the power non-linearly. So, let's say, if the popular APC SmartUPS 420 V A UPS costs $150, then the APC SmartUPS 700 V A is already $250. However, there are inexpensive UPSs that do not equalize the voltage, but only switch to the battery in case of a absence. Prices for such devices are quite affordable - APC BackUPS 500 V A costs about $ 50-60.

Note also that UPS batteries have a life span of 3 to 6 years, and the cost of replacing all the batteries in one UPS is on average half the full cost of a new unit.

At the same time, inexpensive UPSs are usually low-power. Prices for powerful models from the same APC company, such as the Matrix 300 and 5000 V A, start as early as $ 3,000. And the price of models such as Symmetra (APC) with power from 8000 to 8 thousand dollars

Thus, the use of powerful UPS at home turns out to be meaningless, and the use of an inexpensive UPS comes down only to urgently save all files and turn off office equipment in order to avoid data loss.

UPS self-contained power supply

How can we protect ourselves from prolonged power outages? Is it really necessary to buy such expensive and powerful uninterruptible power supplies for this?

There are two options here:

• connect an inexpensive car battery in parallel to a regular IPS battery (by the way, motorists often have fully functional batteries, which they no longer dare to use in winter, but such devices still hold a charge quite well);
• for a couple of car batteries, use a voltage converter from 12 to 220 V.

The first option may well fit as a cheap alternative to the expensive replacement of standard UPS batteries, when the uninterruptible power supply, due to the failure of standard batteries, starts to work only as a surge protector. However, in the event of a deep discharge of a car battery, the use of a non-standard battery on a UPS is fraught with serious problems.

After all, the UPS control circuit, as a rule, is designed only for a standard battery. For example, if you decide to replace the standard 12V7AH battery on the same APC BackUPS 500 V A with a new 12V20AH battery (essentially the same, but more capacious), then when charging, a more capacious battery will take more current and from overheating of wires and circuit elements for sure the control controller will fail (or the overcurrent protection in the recharging circuit will work and charging simply will not work).

As for a car battery, which is much more capacious, the average charging current of a not very discharged battery does not exceed 1/10 of the maximum, so nothing should happen with a shallow discharge. However, after any significant discharge of the additional battery, you will have to disconnect it from the UPS and charge it with a separate charger, which is not very convenient.

What can be done in this situation? Firstly, you can use a separate controller to connect an additional battery for a minimum and maximum voltage(for example, described at http://battery.newlist.ru/chargers_lvd_01.htm). Then additional circuit automatic shutdown load on the minimum and maximum allowable voltage will protect the UPS circuit. You will adjust the response thresholds with potentiometers, and the operating voltage range will be determined by the parameters of the transistors used.

Or, if you plan to use a lead-acid car battery, then the UPS should be chosen not with an alkaline, but with a standard lead-acid battery. Then the UPS recharging circuit will be designed to use batteries with similar parameters, therefore, a discharged car battery will not burn the UPS controller. Of course, any recharging scheme has a certain current limit, and if you hang an external car battery on a very low-power UPS, then the UPS may burn out, especially if you bring the battery to full discharge.

However, you can also use a mixed circuit, when the car battery is charged by a constantly connected charger for car batteries (with overcharge control and other automation) and at the same time the battery is connected to the UPS in parallel with the standard battery. Thus, in this case, the UPS serves only as a voltage converter from 12 to 220 V.

The option with a special 12/220 V voltage converter instead of a UPS is more reliable, but such a high-power voltage converter is comparable in cost to a UPS and, moreover, will still require the purchase of a sufficiently powerful car battery charger. At the same time, a low-power charger charges for a very long time, and a powerful one is quite expensive and has impressive dimensions (that is, along with economic feasibility such a system, it will be necessary to consider its weight and size parameters).

600W 12/220V car adapters cost around $80-100. A 1200W 12/220V voltage converter will cost $200-220, while a 2500-3000W adapter will cost more than $400. you see, even the prices of adapters are already quite comparable with the prices of UPSs of similar power, and we still need a battery charger!

Ready solutions

In principle, the very idea of ​​using car batteries as a source of autonomous power is not new, and Russian industry has several ready-made solutions. So, for example, the company "MicroArt" (http://www.invertors.ru) offers relatively inexpensive devices MAP "Energia" - converters of DC voltage 12 or 24 to AC 220 V (bidirectional inverters) with a power of 0.9 to 12 kW with a built-in intelligent microcontroller that provides automatic control of modes and, if necessary, communication with a computer.

Such a converter simultaneously charges car batteries (one or more) and is used as an autonomous power source: if there is a mains voltage of 220 V, then it simply passes it through itself and, if necessary, recharges the batteries; if the external mains voltage has disappeared, it instantly starts generating 220 V from the batteries. The operating time of such a source depends on the load and capacity of the batteries. So, four batteries of 190 A / h will last for 17 hours at a constant load of 500 W (see table). Also, for example, any car can be used as an autonomous power plant on wheels, and the car engine may not even be turned on for some time. Such a converter is much cheaper than a gas or diesel mini-power plant, miniature and light. The price of converters MAP "Energy" - from 8 thousand rubles. Additionally for 650 rubles. you can purchase a cord, controller and software for connecting this device to a computer (i.e. MAC Energia can completely replace a UPS).

If power outages are very long or there is none at all, then you can use such a converter in conjunction with a mini-power plant (gas or diesel), as well as with alternative sources power supply (solar solar installations and wind generators) for energy storage. In this case, turning on the power plant for only 3 hours a day, you can provide yourself with electricity around the clock!

In addition to using this device as an uninterruptible or autonomous power supply, it can be used both as a DC voltage converter 12 or 24 V (there are two options for devices) to AC 220 V at a frequency of 50 Hz, and as a starting charger for a car.

The device provides protection against overload, short circuit, battery connection with the wrong polarity, overcharging and complete discharge of the battery. In addition, it is equipped with a surge protection system for powered devices and a soft start system, which eliminates high current consumption at the time of start.

Battery life

marginal notes

It should be noted that lead-acid automotive batteries are strongly discouraged from charging in a residential area, as they emit gases during intensive recharging. During operation (discharging), acid batteries are quite harmless. Note that, in particular, this is why UPS batteries are much more expensive - their design is sealed and they have no top ventilation holes. Therefore, it is better to keep the battery economy in a city apartment on the balcony.

Because of this prohibition, I was forced to use chemical current sources. More specifically, these are the batteries:

At first I was engaged in mechanics and electrical engineering, I made various mechanisms with electric motors, but there was nothing to feed them. The electric motors were something like this (with great difficulty I found a photo of the engine on the Internet):

It was very interesting to play with mechanisms made by one's own hands. But through a short time the charge was running out, because the batteries were not at all like modern Duracells, the engines also did not shine with efficiency, and the design made by the child was far from economical. It was not easy to beg adults for new batteries. Maybe they would like to buy them for me, but batteries were sold only in the district center, it’s 25 km to go there, someone didn’t go there every month. So I sat on a starvation diet, sorting through the circle of used batteries, knocking on them with a hammer and pinching them in the front door in order to somehow prolong their work.

At that time, I saw two types of batteries: something like 6ST-55, which were installed in cars, and D-025 disk batteries, which were in a fashionable flashlight that was charged from the mains. Our family did not have such a flashlight. I knew about them only because the neighbors gave me several of these flashlights for spare parts, in which the batteries had lost their capacity. And it happened, according to them, rather quickly. In this flashlight, by the way, there was a very unusual rectifier element. I saw other types of batteries only in pictures in books. Therefore, there was no confidence in the batteries, and they were some kind of exotic. There were batteries left. Swallowing saliva, I looked at the mechanisms working from the network. What a blessing, they could work forever! Since then, a negative attitude towards autonomous power has developed.

When I went to school, I was allowed to work with the network. The first thing I did was an AC lab power supply.

The transformer wound itself, both primary and secondary. I took iron from a burnt-out power transformer of a tube radio. The output voltage was regulated by switching the taps of the secondary winding. As I recall, with what difficulty it was possible to find at least some of the materials - horror. All the sheet aluminum I owned for most of my childhood was a cover from a discarded washing machine"Riga". However, now the materials are not much better. The power supply transformer was fixed with strips of tin, which were screwed to a wooden base with nails with an M4 thread cut into them. Happiness that I had taps and dies with early childhood. Galetnik - and that one is half homemade. I don't remember why it had to be redone. For the front panel, I found a piece of blue plastic. In childhood, there were large sheets of such plastic, they were used somewhere in construction. But this plastic was processed very poorly, it was similar in properties to polyethylene. But I had a piece of foil fiberglass! I cut tracks on it and installed a bridge on the D226 and a capacitor. We can say that the PSU was made on a printed circuit board! This power supply served me all my school years and, in fact, is the most useful design in my life. Although in high school I made a new PSU, more powerful, but I still mostly used the old one.

I also had a PSU for powering lamp structures (+300 V anode and ~ 6.3 V incandescent), but this is an industrial design. In some tube radios, the PSU was carried out on a separate chassis, and that's where I took it from. He also had a case with a panel of the same blue plastic, but, alas, there is no photo of the case. In general, all these photographs were taken recently, before that the devices were lying in the dust of the attic for decades.

In subsequent years, I made designs only with mains power. Stand-alone devices are something inferior. For example, a portable tape recorder is always worse than a stationary one, and a portable receiver is worse than a radiogram. And it's good if the tape recorder has a mains power supply. Otherwise, there will be eternal torment with batteries, which are not at hand when necessary. The same applies to other instruments, such as measuring instruments. A sign of high class is mains power supply.

The next time I ran into battery life was in 1998, when I decided to give myself a generous 30th birthday present and bought a Panasonic SL-S200 portable CD player on the market.

At that time, I already had a stationary CD player made from the wreckage of a Sony car player. Homemade case, homemade power supply and analog part, additional AT89C2051 processor for implementing IR remote control.

Together with the Panasonic SL-S200, the sellers decided to sell me GP batteries and a charger for them. Panasonic itself had a mains power supply, but at 110 V. Good sellers gave it a small autotransformer, “saffron milk cap”, as it was called for Brown color plates. Of course, I did not use it, but redid the power supply unit, replacing the transformer in it. The case was taken from some other adapter, the native one was too small. Only the nameplate was carefully cut out and pasted into its body.

I also had to immediately abandon the headphones that came with the kit. But I had Sony MDR-14s bought from the store for $16. In general, it was an interesting time then - in a store on the central avenue of the capital, they officially traded for dollars. I gave twenty (and it was then a lot of money), from the cash register they got me change - 4 units. GP batteries were no match for batteries. Moreover, there was nowhere to charge them - the purchased charger emitted smoke when it was first turned on. So I was once again disappointed in the batteries. The player listened mainly at home, feeding it from the network. Mobility was needed only within the apartment. I tried to take it with me somewhere, but I don’t want to listen to music outside the house. So he spent more than 16 years, almost without leaving home.

The next time life pushed me again with autonomous power was the purchase of the first Nikon 2100 digital camera. Batteries labeled Nikon were included. Of course, out of habit, I decided to be powered by batteries. But was frustrated by how quickly they run out. Surprisingly, the batteries lasted much longer. Moreover, the kit included a fast charger, also from Nikon. For the first time in my life I saw something good in batteries. I really wanted to buy the same batteries as a second set. It is unlikely that Nikon makes batteries itself, most likely, it takes from someone else. I began to closely examine the batteries for sale. The Sanyo batteries were exactly the same, even the letters HR on the bottom were stamped in the same way. Only they had a capacity of 2300, and those with a Nikon label, 2100.

Frightened by bad batteries, GP hesitated to buy these Sanyo for a long time, because batteries are not cheap things. But I bought it anyway. In life, joy rarely happens, but here is exactly the case. Purchased batteries lasted as long as the native ones.

When it came time to change the camera, the question arose of charging 4 AA batteries. An attempt was made to make your charger no worse than the purchased one. But this attempt failed. I don’t understand how a network pulser fits in such a small size, and even a charging control circuit individually for each of the 4 batteries. As a result of much thought, a Duracell charger was written and bought for a lot of money - as much as $ 40.

For the camera, I bought a set of the same Sanyo batteries, then another one - they worked perfectly. One of the sets was very old, it was time to change. But once again, the purchased batteries turned out to be quite weak - about 3 times less capacity. And they didn't look any different. The chagrin was huge, because a lot of money was spent. But what to do, batteries are needed, I decided to take another chance - I bought a Sony kit. And again failure. I got angry again at the address of autonomous power supply, but the camera is that rare exception when its operation near the outlet is almost impossible. I read on the forums that solid fakes are now being sold, it is impossible to buy normal batteries. I read that Ansmann, it seems, is not yet faked. I bought a kit with a modest capacity of 2100 and was satisfied. Again at the level of the good old Sanyo.

In a SLR lithium battery. At first I was worried about this - it is impossible to buy batteries in the nearest kiosk in which case. But the camera is so economical that I completely forgot the problem of batteries. But the on-camera flash is powered by 4 AA batteries. I also needed to buy something. I analyzed the reviews and bought again Sanyo, but now a new line of Eneloop. They turned out to be great batteries.

Another device where there is no way without a battery is mobile phone. By itself, of course, the phone is not so necessary if you do not work as a dispatcher or a pizza delivery man, but if you have it, you need to keep it in working order. So you have to regularly buy new batteries. Also come across different quality, there's nothing to be done.

On duty, he made many different electronic devices. But almost never made autonomous ones. Is it a thermometer that is powered by 2 AA batteries or from the mains, in connection with which a SEPIC converter is used there, which can both increase the battery voltage to 3.3 V and lower the voltage of the AC adapter.

What am I getting at? Recently, quite often radio amateurs are trying to make self-powered devices. I do not understand this. There are a lot of problems there as well. It is not enough to provide performance, you must also ensure low consumption. Why limit yourself to such limits? Well, if someone thinks that he will use the device in the field, then he automatically puts himself on the lowest rung of the hierarchy of industry workers: life on business trips instead of working in a cozy office at his own desk in a comfortable chair.

P.S. I forgot about one device where autonomous power is justified. This is a clock. As a result of the fact that the consumption is small, you rarely have to change the batteries (once every few years), this can be tolerated. But there is also a downside to low power consumption - nothing can be seen on such a watch in the dark.