Choosing a UPS for a gas boiler: how to find a high-quality uninterruptible power supply?

The principle of operation of an uninterruptible

The main task of the UPS is to supply sufficient power to the network when the light is turned off. Switching to battery power (batteries) must occur in a fraction of a second so that the connected equipment does not have time to turn off.

Uninterruptibles are also able to stabilize the voltage, rectify the sinusoid and maintain the current frequency within the normal range. But not all models have additional features.

When choosing an uninterruptible power supply for the heating system, you can take a more powerful device so that you can additionally connect other devices to it if necessary

The UPS device is not the same. In the maximum configuration, the uninterruptible power supply consists of the following elements:

• frame;
• accumulator battery;
• current and voltage converters (inverters, rectifiers, etc.);
• switch;
• control chip.

The following characteristics of the UPS are important for the operation of the connected equipment:

1. Type of output voltage curve: approximated or normal sinusoid. The first option is less preferable, because it is unusual for most electronic devices and leads to their increased wear.
2. Power consumption. The pump and fan motors have high starting currents, so the maximum output of the UPS must be at least 2 times the power consumption of the boiler.
3. Switchover speed to redundant power supply. The higher it is, the better for the connected equipment.
4. electrical capacitance. The battery life of the entire heating system depends on it. Additional external batteries can be connected to the UPS to increase capacity.
5. Life time. It depends on the mode of operation and the internal structure of the batteries.
6. The range of incoming network parameters that allow the uninterruptible power supply to produce acceptable voltage, frequency and sinusoid without switching to the battery.
7. The presence of grounding ("through" zero).

In offline mode, the UPS is capable of producing 2 types of sine waves:

• smooth;
• approximated.

A smooth sine wave is more acceptable and will always ensure that the connected equipment operates normally.

The specified periods of operation of the equipment from the uninterruptible power supply are indicative. The exact time can be found by testing a specific set of equipment

The cost of uninterruptibles directly depends from battery capacity, additional functionality, as well as the compliance of the output parameters of current and voltage with standard values. However, even the cheapest UPS is better than none at all.

How to choose an uninterruptible power supply for the boiler

UPS, which are used to power gas boilers, are distinguished by the following features:

• The sinusoidal form of the output voltage when operating from the mains and from the battery is achieved by on-line technology (“double conversion”);
• High-capacity batteries - provide long-term operation in the absence of power supply (tens of hours);
• Wide input voltage range at which the UPS does not connect the battery;
• Input voltage filtering, which reduces output distortion to less than 3%;
• Battery deep discharge protection system - increases the life of the UPS;

The presence of By-Pass mode - prevents damage to the UPS in the event of a breakdown, accompanied by a short circuit and exceeding the maximum allowable load.

Advantage of On-Line UPS

The cost of the kit depends on the type of UPS. There are three of them: OFF-Line, Line-Interactiv, On-Line. There is no golden mean. The wrong choice of UPS type can damage the boiler electronics, which are expensive to replace and always at the wrong time (in winter).

Explanation: Line-Interactiv UPSs are cheaper, but they can only be used for gas boilers in stable power networks. The presence of a voltage stabilizer inside such UPSs is not an advantage - but a disadvantage, because.this stabilizer is actually rough and is the reason for the appearance of power surges at the output of the UPS, which are dangerous specifically for gas boilers. These UPSs can only help when there is a power outage. They do not save from interference, sudden power surges. This is described in more detail in our article: contraindications when used with gas boilers. This type of UPS is ideal for solid fuel heating systems. You can make the network stable by installing a thyristor or inverter voltage stabilizer.

UPS types

There are dozens of manufacturers on the market that produce uninterruptible power supplies for various price segments. However, in budget models, functionality and battery life are many times inferior to expensive devices.

According to the principle of operation, the equipment is divided into 3 categories:

• Reserved (offline);
• Continuous (online);
• Line interactive.

Now in detail about each group.

Reserve

If there is electricity in the network, then this option acts as an intermediary.

As soon as the power is turned off, the UPS automatically transfers the connected device to battery power.

Such models are equipped with batteries with a capacity of 5 to 10 Ah, which is sufficient for correct operation for half an hour. The main function of this device is to prevent the instantaneous stop of the heater and give enough time to the user to properly turn off the gas boiler.

The advantages of such a solution include:

• Noiselessness;
• High efficiency if the power is supplied through the electrical network;
• Price.

However, redundant UPSs have a number of disadvantages:

• Long switching time, on average 6-12 ms;
• The user cannot change the characteristics of voltage and current;
• Small capacity.

Most devices of this type support the installation of an additional external power supply. That's why battery life increases many times. However, this model will remain a power switch, you can not demand more from it.

Continuous

This type works regardless of the output parameters of the network. The gas boiler is powered by battery power. In many ways, this became possible due to the two-stage conversion of electrical energy.

The voltage from the network is fed to the input of the uninterruptible power supply. Here it decreases, and the alternating current is rectified. Due to this, the battery is recharged.

With the return of electricity, the process is carried out as follows. The current is converted to AC, and the voltage increases, after which it moves to the UPS output.

As a result, the device works properly when the electricity is turned off. Also, unexpected power surges or distortion of the sinusoid will not cause a negative effect on the heating device.

The advantages include:

• Continuous power even when the light is turned off;
• Correct parameters;
• High degree of security;
• The user can independently change the value of the output voltage.

Flaws:

• Noisy;
• Efficiency in the region of 80-94%;
• High price.

Line Interactive

This type is an upgraded standby device. So, in addition to batteries, it has a voltage stabilizer, so the output is always 220 V.

More expensive models are able not only to stabilize the voltage, but also to analyze the sinusoid, and in the case when the deviation is 5-10%, the UPS will automatically switch the power to the battery.

Advantages:

• Translation occurs in 2-10 ms;
• Efficiency - 90-95% if the device is powered by a home network;
• Voltage stabilization.

Flaws:

• No sine wave correction;
• Limited capacity;
• You cannot change the frequency of the current.

Pure sine and its effect on the boiler

First of all, when choosing a UPS for a boiler, pay attention to the shape of the output voltage. There are 2 types of output voltage:

There are 2 types of output voltage:

pure sine

quasi-sine (meander signal)

When choosing, always focus on pure sine models

Why is it important?. Boilers and its equipment do not like both voltage drops and changes in the frequency of the output signal

If you buy a UPS with a quasi-sine, the boiler may recognize this voltage as an error, and will go into an accident

Boilers and its equipment do not like both voltage drops and changes in the frequency of the output signal. If you buy a quasi-sine UPS, the boiler may recognize this voltage as an error, and will go into an accident.

Of course, the wrong sine is not terrible for electronics. But the pumps of heating equipment, such as RS or UPS, begin to buzz.

The motor in the pumps is asynchronous and this pseudo sine produces a lot of harmonics, which significantly reduce efficiency and cause heating and hum.

In addition, the boiler itself has its own built-in circulation pump, and sometimes more than one, hence such stringent requirements.

Always pay attention to the ability of the UPS to withstand large inrush currents (two to three times).In addition to the boiler itself, there is also other equipment that needs to be powered, such as a submersible pump

How to choose the right UPS?

Before buying a power supply, you should clarify a few points.

• The total power of the boiler and circulation pump.
• Required running time.
• Heater fuel type.

Let's start with point 1. Each pump has a starting current. For this reason, the power indicated in the instructions must be multiplied by 3. For example, a heater (50 W) a pump (150 W), multiplied by a factor, we get 500 W. Therefore, the UPS Power must be greater than this figure, otherwise the heater will not start.

On the second point, everything is simple. Are there short-term power outages in your area? an uninterruptible power supply with a built-in battery is suitable. Do you want to make sure or there is no light for 3-4 hours? It is worth buying a device with the ability to connect additional batteries.

A gas boiler is installed - preference should be given to double conversion devices. Solid fuel heaters are less whimsical, put "interactive" or "backup" UPS.

UPS types

Always try to buy those inverters that have a built-in voltage regulator.

According to this parameter, the UPS can be divided into 3 types:

off line - what voltage is supplied to them, this is what comes out

A variable 200V was applied, the same variable 200V was received at the output. If the network parameters deviate beyond the minimum or maximum ranges, it will simply turn on the inverter and begin to take energy from the battery.

Some people wonder why their batteries drain so quickly. Although there were no outages. Just check the input voltage and everything will become clear.

on-line - in them, the alternating voltage is first converted to constant, corrected, and then alternating is again issued

That is, all bad network parameters (sinusoid, voltage drops, frequency) are leveled and smoothed to nominal values.

linear-interactive - they do not convert the frequency, but there is only a built-in stabilizer

The best and most perfect models today are online.

They must be installed if you have temporary or long-term power from the generator.

There are often problems with a frequency other than 50Hz.

Kinds

Manufacturers of heating equipment represent many different devices. This allows you to choose an option for any financial possibilities and technical requirements. Depending on the principle of operation of uninterruptible power supplies, there are backup, line-interactive, online. Let's consider each of them in detail.

Reserve (standby)

This is a simple, inexpensive, and therefore common type of equipment. In normal mode, the boiler is powered directly from a household outlet, and the transition to batteries occurs within a few milliseconds after a power outage.

Pros and cons

affordable price
ease of maintenance and repair

the non-sinusoidal output waveform negatively affects the equipment, but there are models with a pure sine output, and their price is noticeably higher
inability to adjust the voltage
built-in capacity battery for heating boiler low, but it is possible to connect external batteries

Line-interactive (line-interactive)

The advantage of this circuit over the previous one will be the ability to stabilize the load supply voltage in the event of an increase or decrease in the voltage in the mains. Batteries, or rather, their energy, the system uses only in the absence of the main power supply, which increases their service life. Devices are produced in two groups depending on the form of output voltage in battery mode.

The most widely used devices have an approximated sinusoid. Their purpose is to work with switching power supplies provided in personal computers. If you need a source to provide power to electric motors, coupled with circulation pumps, the latter are more suitable.

Pros and cons

high efficiency
built-in voltage stabilization function
quick transition to offline mode when the mains voltage is turned off

mains voltage is not completely filtered from RF interference
it takes up to 20 ms to switch from mode to mode, however, this is not true for all models

Online (on-line UPS)

The most technologically advanced double conversion uninterruptible power supplies not only ensure uninterrupted power supply, but also improve power quality. That's why they cost a little more than their previous counterparts. Their use is justified only by the need for a very high quality power supply.

Pros and cons

there is no time interval between the mains disconnection and the start of battery operation
stabilized output voltage

complex device
relatively high price
in some models, the fans for cooling the inverter are very noisy

UPS or generator - what to choose?

The generator is used in the event of a power outage. It is necessary to switch the power supply system to the generator, start it and wait until it enters the mode and connect the load.

The average price of equipment is 30,000 rubles, but there are also more expensive items. Their advantages are in the possibility of using energy supply at any time. The disadvantage is the need to control the operation of the system.

IMPORTANT!
UPS is the best solution. The advantage of the system is the presence of an online mode for automatic switching of the mode. The presence of a person during the operation of the UPS is not required

The device copes well with power outages

The presence of a person during operation of the UPS is not required. The device copes well with power outages.

UPS rating for boilers

The TOP boilers include devices with the best, according to experts, characteristics. They have different types of designs.

Helior Sigma 1 KSL-12V

The UPS is equipped with one external battery. The device is adapted to Russian electrical networks. Weight 5 kg. Operating voltage 230 W. According to the type of construction, the model belongs to On-Line devices. On the front panel of Helior Sigma 1 KSL-12V there is a Russified LCD display showing network indicators. Input voltage range from 130 to 300 watts. Power 800 W. The average cost of an uninterruptible power supply is 19,300 rubles.

Advantages:

• There is a special mode of operation with generators.
• Compactness.
• Reliability, long service life.
• Silent operation.
• The presence of a self-test function.
• Low power consumption.
• Doesn't overheat during extended use.
• Long battery life.
• Possibility of self-installation.
• Affordable price.

Flaws:

• The input voltage has a narrow tolerance range.
• Small battery capacity.

Eltena (Intelt) Monolith E 1000LT-12v

Chinese made product. Refers to On-Line devices. Fully adapted to work with Russian electrical networks. Input voltage range from 110 to 300 V. Power 800 W. The choice of voltage power occurs in automatic mode. Weight 4.5 kg. There is a Russified LCD display. The average cost of the model is 21,500 rubles.

Advantages:

• The relevance of the charging current for connecting to a battery with a capacity of 250 Ah.
• Optimal input voltage range.

The disadvantage is the high price.

Stark Country 1000 online 16A

The device is manufactured in Taiwan. The model was updated in 2018. Power 900 W. The UPS is designed to operate with two external circuits. The bespereboynik provides full protection of a copper at emergency shutdown of the electric power. Weight 6.6 kg. The average cost of the device is 22800 rubles.

Advantages:

• Automatic selection of operating power.
• Ability to work offline 24 hours.
• Battery protection against deep discharge.
• Wide input voltage range.
• Possibility of self-installation and ease of operation.

Flaws:

• Short wire.
• Average noise level.
• High price.

HIDEN UDC9101H

Country of origin China. The UPS is adapted to work with Russian electrical networks. It is considered the quietest uninterruptible unit in its class. It has an automatic system for adjusting the operation of the cooling system, so it never overheats during prolonged use. Power 900 W. Weight 4 kg. The average cost is 18200 rubles.

Advantages:

• Long service life.
• Reliability at work.
• Wide input voltage range.

• Intelligent control system.
• Compactness.

The disadvantage is the need for initial setup.

Lanches L900Pro-H 1kVA

Country of origin China. Power 900 W. The interrupter has a high efficiency. The model is adapted to the loads of Russian electrical networks, has an LCD display. It displays the mains input voltage parameters and other indicators of operating modes, including the battery charge level. The package includes software. Weight 6 kg. The average selling price is 16,600 rubles.

Advantages:

• Resistance to power surges.
• Affordable price.
• Reliability of work.

• Ease of operation.
• Long battery life.

The main disadvantage is the low charge current.

Energy PN-500

The domestic model has the function of a voltage stabilizer. Available in wall and floor versions. Operating modes have sound indication. A special fuse is installed to protect against short circuits. The graphic display is multifunctional. The average cost is 16600 rubles.

Advantages:

• Input voltage stabilization.
• Overheat protection.

• Design reliability.
• Long service life.

Flaw - high noise level.

SKAT UPS 1000

The device differs in the increased reliability in work. Power 1000 W. It has the function of an input voltage stabilizer. The input voltage range is from 160 to 290 V. The average sale price is 33,200 rubles.

Advantages:

• High work precision.
• Automatic switching of operating modes.

• Reliability at work.
• Long service life.

The disadvantage is the high price.

Redundant Power Supply Selection Criteria

Redundant power supplies designed to work with heating system pumps should be selected according to several characteristics:

• Power;
• Battery capacity;
• Allowable battery life;
• Ability to use external batteries;
• Input voltage spread;
• Output voltage accuracy;
• Transfer time to reserve;
• Output voltage distortion.

Choosing a UPS for a circulation pump should be based on several basic parameters, the determining one of which is power.

Determination of the required power of the UPS

The electric motor, which is an integral part of the heating system pump, is an inductive type reactive load. Based on this, the UPS power for the boiler and pump should be calculated. The technical documentation for the pump may indicate the power in watts, for example, 90 W (W). In watts, heat output is usually indicated. To find out the total power, you need to divide the thermal power by Cos ϕ, which can also be indicated in the documentation.

For example, the pump power (P) is 90W, and Cos ϕ 0.6. Apparent power is calculated by the formula:

Р/Cos ϕ

Hence, the total power of the UPS for normal operation of the pump should be equal to 90 / 0.6 = 150W. But this is not yet the final result. At the moment of starting the electric motor, its current consumption increases by about three times. Therefore, the reactive power should be multiplied by three.

As a result, the UPS power for the heating circulation pump will be equal to:

P/Cos ϕ*3

In the above example, the power supply will be 450 watts.If the cosine phi is not specified in the documentation, the thermal power in watts should be divided by a factor of 0.7.

Battery capacity

Battery capacity determines the time during which the heating system pump will work in the absence of a network. The batteries built into the UPS usually have a small capacity, determined primarily by the size of the device. If the backup power source will operate in conditions of frequent and prolonged power outages, you should choose models that allow connecting additional external batteries.

A very informative video about the personal experience of a person who was faced with the purchase of an inverter for a boiler and a heating pump, see:

Input voltage

The mains voltage standard of 220 volts assumes a tolerance of ± 10%, that is 198 to 242 volts. This means that all devices used on the territory of the Russian Federation must work correctly within these limits. In fact, in various regions, and especially in rural areas, deviations and power surges can significantly exceed these values. Before purchasing a UPS for a heating pump, it will be very useful to measure the mains voltage repeatedly, during the day. The passport for the backup power source indicates the permissible input voltage limits, at which the device provides an output voltage close to the nominal value.

Output voltage and its shape

If the output voltage parameters uninterruptible power supply fit within the allowable 10 percent, then this device is quite suitable for powering the pump of the heating system.The time it takes for the control board to switch to battery power is typically less than tens of microseconds. For an electric motor, this parameter is not critical.

A very important parameter of the UPS, which is necessary for the correct operation of the heating system pump, is the shape of the output signal. The pump motor requires a smooth sine wave, which only a double conversion device or an on-line UPS can provide of all backup power models. In addition to the ideal sine wave at the output, this source also gives the exact value of voltage and frequency.

When installing a UPS for a heating pump, some rules should be followed:

• The temperature in the room must correspond to the values ​​\u200b\u200bspecified in the documentation;
• The room should not contain vapors of caustic reagents and flammable liquids;
• The ground loop must be made in accordance with the rules for the operation of electrical installations.

How to properly install and operate

Installing the UPS is quite simple - just read the instructions and connect all external devices according to the scheme described in it.

The efficiency of powerful uninterruptible power supplies is reduced due to continuous operation of the fan, which provides cooling for the current converters and batteries located inside

Operation of uninterruptible power supplies is simple and does not require human intervention.

However, there are nuances of operation that are not described in the instructions, which you must definitely familiarize yourself with:

1. Do not place the UPS and external batteries near each other and heat sources. The optimum temperature for the operation of this equipment is 20-25 °C.
2. The room with uninterruptible power supplies should not be damp, the formation of water condensate in it is especially dangerous.
3. It is undesirable to use mains filters and tees at the output of the UPS.
4. If the design of the uninterruptible power supply provides for the presence of grounding of the case, then it must be provided.
5. The UPS must be permanently connected to the mains after commissioning.

Backup power source in the heating system

Any heating, especially in winter, should occur without failures and stops. The fact is that in addition to the electronic control system, electrical energy is required for the circulation pump, which pumps the coolant through the heating system.

Stopping the circulation pump in severe frosts can lead to the most serious consequences. Therefore, the power supply of the heating system of a private house must be carried out with the obligatory connection of an emergency power source.

A UPS with a battery must ensure the correct operation of the heating system for several hours. For normal operation of the pump and fan, the emergency power supply unit must produce a sinusoid of the correct form without steps and distortions. Otherwise, asynchronous electric motors will work in hard mode and may fail.

In heating systems, different types of emergency power sources may be used, which may differ in technical characteristics.