- Why voltage stabilization is so important
- Network parameters
- Types of stabilizers
- Uninterrupted power supply
- Comparison of models
Today we’ll talk about choosing a voltage stabilizer for a heating boiler. While the quality of power supply from municipal networks leaves much to be desired, we continue to take care of providing a number of sensitive devices with a stable voltage. This is especially important for electronically controlled boilers, the ideal way to achieve this is to install a stabilizer.
Why voltage stabilization is so important
At the beginning of the century, it became clear that boilers are no longer just gas water heaters. Today these are real mini-boiler houses, equipped with both telemetry and self-diagnostics means, and executive devices: a pump, a gas shut-off valve, an automatic coolant feed system. At the same time, the user is not obliged to learn how to operate this equipment and know everything about the operating modes. The built-in microcontroller will take care of this: some gas boilers are superior in intelligence to washing machines and other newfangled home appliances.
Quite complex algorithms for controlling the functional organs of the boiler are hidden inside the electronic unit. Many foreign models of heating equipment do not just use high-quality radio components, each separately taken control board is individually configured. Because of this, the loss of the electronic part for most expensive boilers is considered irreparable, while representatives of a lower price category require service repairs, during which the house will remain without heating..
The main reason for the failure of the boiler electronics is considered to be operation with poor parameters of the power supply network. A closer look at the insides reveals an interesting picture. On board the Ferroli or Viessman boilers there are stabilized input converters with a cascade of filters, but only they are designed for the noise level typical for the power grids of Western countries. At the same time, the works of Chinese craftsmen do not even have a primitive protection against overload. And therefore, a stabilizer or a stabilized UPS is needed for both cheap and expensive boilers, in the end, the main danger is either the freezing of the house or the emergency operation of gas equipment..
But how exactly can the electrical network affect the performance and what are the negative factors? Is it possible that the capabilities of the built-in converter will be enough to eliminate dangerous oscillations? The answers to these questions not only determine the need to install a stabilizer, they allow you to understand which device will be unnecessarily expensive due to an unreasonably wide range of functions..
By connecting multiple batteries, you can increase the operating time of the uninterruptible power supply up to 24 hours or more.
The main hazard is power outages. Stopping circulation is a direct way to stop the operation of the entire system, and its sudden occurrence leads to the supply of a portion of the cooled coolant inside the still hot heat exchanger – to the so-called temperature shock. When installing the UPS, these risks disappear, but the presence of a battery and a converter in the stabilizer sometimes increases its cost by 2-3 times. If you are not sure – wait with the purchase, then nothing will prevent you from completing the scheme with a budget option: an old UPS (UPS) with a failed battery and a car battery.
The second parameter is the stability of the voltage amplitude. Equipment with a built-in input converter is not sensitive to dips up to 150 V, while the circuit components allow an increase in the voltage in the network up to 270 V without harm to the control circuit. Note that if the boiler is powered through the UPS, the threshold for the latter will be less than the limit of the electronics. For boilers without an input converter, the installation of a voltage stabilizer is strictly required.
One excessive power surge, a power failure on the control board, is enough to destroy it. Even with a small risk of such an outcome, it is better to take care of the uninterrupted operation of the heating boiler in advance..
Even with input stabilization, the electronic circuit remains extremely vulnerable to surges and interference. An external stabilizer will help turn off the power to the boiler in case of dangerous parameters of the supply network and smooth out harmful fluctuations. Of course, it was possible to limit oneself to the installation of an SPD and a voltage relay in the boiler room, but the total cost of these devices is quite comparable with the budget samples of network stabilizers..
Types of stabilizers
Stabilizers for boilers differ from general house ones only in their load capacity, their low cost corresponds to the power class. By design and principle of operation, these devices are traditionally divided into servo, relay and electronic. Looking ahead, we say that the reliability and quality of the stabilizer almost does not depend on its family, much more important is the set of protective functions.
If you are using a reliable, expensive boiler unit, it is better to contact your sales consultant or read the operating instructions for recommendations on choosing a stabilizer. The manufacturer will himself recommend a suitable rectifier model from its own range, or announce the required set of parameters. Often, the cost of even a branded device does not greatly exceed the general price threshold, but reliability and full compatibility of technology is guaranteed.
If the requirements for the stabilizer are described by general recommendations, you will have to find out the reasons for the price spread for different models with the equipment supplier. Here are some examples of additional features and features that account for the increased cost of the instrument:
- Load capacity is a value measured in volt-amperes that determines the allowable power of the connected equipment. Boilers in fact can demonstrate different consumption depending on the quality of the power supply circuit, the presence of a built-in circulation pump and other actuators. It is important that the throughput is chosen with a margin of 25-30% of the boiler power, because at the lower voltage limit, the efficiency of the converter is greatly reduced.
- All kinds of protection. It is preferable for a stabilizer to have a wide range of feedback protections. A relay cut-off of the input filter-rectifier is recommended; for this, a standby voltage generator must be present in the device. The second stage of protection against internal short-circuits must be performed by a fuse.
- The presence of active cooling – for electronic stabilizers with a power of connected devices over 500 W, other types – over 1 kW.
- High efficiency – this indicator is of critical importance only if the stabilizer has to work in a constant pull-up mode with deviations of 25-30% from the nominal level. Also, you should not trust the statement about an unprecedented high efficiency: alas, but losses in electrical converters of less than 5% are still demonstrated only in the space industry and high-precision technology.
- The operating voltage range is entirely determined by the device family. Electronic stabilizers have a significant advantage in this plan, servo drives are the most lagging behind..
- The purity of the output voltage curve determines the quality of the stabilization. For boilers without an integrated converter, a pure sine wave is required, while with even the simplest cascade of input filters, slight disturbances and oscillations are already permissible.
Uninterrupted power supply
A separate criterion for household stabilizers is the availability of an autonomous power source, which allows maintaining the full operation of the boiler house during the period of a power outage. The operating time is determined by the battery capacity and the efficiency of the converter circuit.
There are two types of stabilizers that provide uninterrupted power. Some of them have a built-in battery, such are designed primarily for powering the boiler automation and boiler room alarm. More advanced devices are designed to connect an external battery, while they can maintain the operation of pumps, electric valves and other actuators for a long time. An important point: if the load does not change during the operation of the pumps and the control unit, then when the servos of the dampers and blowing fans are turned on, the total energy consumption is more difficult to predict.
In general, the same requirements apply to UPS devices for boilers as for stabilizers. The only exception is the type of device architecture, according to which the UPS is divided into off-line, on-line and line-interactive.
Off-line devices do not have a built-in stabilizer and therefore switch to battery operation every time when unacceptable parameters of the mains appear. The difference between interactive and online sources lies in the more advanced current conversion circuit. In fact, the output converter of the line-interactive UPS always operates from a constant low voltage, which can be either the secondary winding of the transformer or the battery. UPS of the last two types are most preferable for power supply of automation and executive devices of the boiler room. You should also pay attention to the switching time of the operating modes, this indicator is better to agree with the boiler manufacturer.
Comparison of models
As a summary of our review, we offer a comparative table of devices for stabilization and uninterruptible power supply of boilers of various types:
Model A type Power (kVA) Input voltage range Stabilization error Protection Dimensions and weight The cost Notes Teplocom ST-555 Relay 0,4 145-260V +/- ten% Overvoltage and overload 130x170x85 mm, 2 kg 3800 rbl. For insensitive electronics Luxeon EDR-1000 Triac 0.7 90-270V +/ – 4-7% Against overload, overvoltage, overheating, short circuit, surge voltage 230x140x178 mm, 4.2 kg 4000 rub. For a wide range of devices EnergyARS-1500 Relay 1.5 140-260V +/- 4% Overload, overvoltage, overheating and interference 375x238x110 mm, 4.3 kg 6500 rbl. For a wide range of devices Daewoo DW-TM12kVA Relay 12 140-270V +/- 4% Overload, short circuit, interference and overvoltage 511x381x259 mm, 23.5 kg 20,000 rubles. Active cooling, for high power devices Lenz Technic R 500W Relay 0.5 140-270V +/- five% Against overvoltage, overheating and short circuit 155х194х122 mm, 3 kg 2600 rbl. Designed in Europe Rucelf SDF-1000 Servo motor 1 120-275V +/ – 1.5% Against voltage surges, interference, overload and short circuit 210x165x205 mm, 5.7 kg 2800 rbl. High accuracy Ortea Aquarius ET30-15 on IGBT keys ten 187-265V +/ – 0.5% Full range of protections 1200х670х410 mm, 130 kg 420,000 rubles. Made in Italy, three-phase connection SVEN Reserve Home – 1000 line-interactive 0.6 150-275V +/- ten% Against voltage surges, short circuits and overloads 140x214x367 mm, 9.3 kg 10 800 rub. Uninterrupted power supply from a battery with a capacity of 10-60 A * h Logic Power LPM-PSW 3000 line-interactive 2.1 145-280V +/- ten% Full range of protections + battery control 350х190х450 mm, 15.3 kg RUB 26,000. Uninterruptible power supply, external battery