(and how to decrypt it)
The optimal source of energy for heating the evaporation tank is a residential electrical network with a voltage of 220 V. You can simply use a household electric stove for these purposes. But, when heating on an electric stove, a lot of energy is spent on useless heating of the stove itself, and is also radiated into the external environment from the heating element, without doing any useful work. This wasted energy can reach decent values - up to 30-50% of the total power expended on heating the cube. Therefore, the use of conventional electric stoves is irrational from an economic point of view. After all, for every extra kilowatt of energy you have to pay. It is most effective to use elec- tronics embedded in the evaporation tank. Heating elements. With this design, all energy is spent only on heating the cube + radiation from its walls to the outside. The walls of the cube must be thermally insulated to reduce heat loss. After all, the cost of heat radiation from the walls of the cube itself can also amount to 20 percent or more of the total power expended, depending on its size. For use as heating elements embedded in a container, heating elements from household electric kettles or other suitable sizes are quite suitable. The power of such heating elements varies. The most commonly used heating elements with a power stamped on the body are 1.0 kW and 1.25 kW. But there are others.
Therefore, the power of the 1st heating element may not correspond to the parameters for heating the cube and may be more or less. In such cases, to obtain the required heating power, you can use several heating elements connected in series or series-parallel. By switching various combinations of connecting heating elements, a switch from a household electric. plates, you can get different power. For example, having eight embedded heating elements, 1.25 kW each, depending on the switching combination, you can get the following power.
- 625 W
- 933 W
- 1.25 kW
- 1.6 kW
- 1.8 kW
- 2.5 kW
This range is quite enough to adjust and maintain the required temperature during distillation and rectification. But you can get other power by adding the number of switching modes and using different switching combinations.
A series connection of 2 heating elements of 1.25 kW each and connecting them to a 220V network gives a total of 625 W. A parallel connection gives a total of 2.5 kW.
We know the current voltage in the network, it is 220V. Next, we also know the power of the heating element, knocked out on its surface, let’s say it’s 1.25 kW, which means we need to know the current flowing in this circuit. Knowing the voltage and power, we find out the current strength from the following formula.
Current = power divided by line voltage.
It is written like this: I = P / U.
Where I is the current in amperes.
P is power in watts.
U is the voltage in volts.
When calculating, you need to convert the power indicated on the heating element body in kW into watts.
1.25 kW = 1250W. We substitute the known values into this formula and get the current strength.
R = U / I, where
R - resistance in Ohms
U - voltage in volts
I - current in amperes
We substitute the known values into the formula and find out the resistance of 1 heating element.
Rtotal = R1+ R2 + R3, etc.
Thus, two series-connected heating elements have a resistance of 77.45 Ohms. Now it is easy to calculate the power released by these two heating elements.
P = U2 / R where,
P - power in watts
R is the total resistance of all sequences. conn. heating elements
P = 624.919 W, rounded to 625 W.
Table 1.1 shows the values for series connection of heating elements.
Table 1.1
| Number of heating elements | Power(W) | Resistance(Ohm) | Voltage(V) | Current(A) |
| 1 | 1250,000 | 38,725 | 220 | 5,68 |
| Serial connection | ||||
| 2 | 625 | 2 heating elements =77.45 | 220 | 2,84 |
| 3 | 416 | 3 heating element =1 16.175 | 220 | 1,89 |
| 4 | 312 | 4 heating element = 154.9 | 220 | 1,42 |
| 5 | 250 | 5 heating element = 193.625 | 220 | 1,13 |
| 6 | 208 | 6 heating element = 232.35 | 220 | 0,94 |
| 7 | 178 | 7 heating element=271.075 | 220 | 0,81 |
| 8 | 156 | 8 heating element = 309.8 | 220 | 0,71 |
Table 1.2 shows the values for parallel connection of heating elements.
Table 1.2
| Number of heating elements | Power(W) | Resistance(Ohm) | Voltage(V) | Current(A) |
| Parallel connection | ||||
| 2 | 2500 | 2 heating element = 19.3625 | 220 | 11,36 |
| 3 | 3750 | 3 heating element = 12.9083 | 220 | 17,04 |
| 4 | 5000 | 4 heating element = 9.68125 | 220 | 22,72 |
| 5 | 6250 | 5 heating element = 7.7450 | 220 | 28,40 |
| 6 | 7500 | 6 heating element = 6.45415 | 220 | 34,08 |
| 7 | 8750 | 7 heating element=5.5321 | 220 | 39,76 |
| 8 | 10000 | 8 heating element = 4.840 | 220 | 45,45 |
Another important advantage that the series connection of heating elements gives is that the current flowing through them is reduced several times, and, accordingly, the heating element housing is low, thereby preventing the mash from burning during distillation and does not introduce an unpleasant additional taste and smell into the final product. Also, the operating life of the heating elements, with this inclusion, will be almost eternal.
Calculations were performed for heating elements with a power of 1.25 kW. For heating elements of other power, the total power must be recalculated according to Ohm’s law, using the above formulas.
Therefore, the power of the 1st heating element may not correspond to the parameters for heating the vessel and may be more or less. In such cases, to obtain the required heating power, you can use several heating elements connected in series or series-parallel. By switching various combinations of connecting heating elements, a switch from a household electric. plates, you can get different power. For example, having eight embedded heating elements, 1.25 kW each, depending on the switching combination, you can get the following power.
- 625 W
- 933 W
- 1.25 kW
- 1.6 kW
- 1.8 kW
- 2.5 kW
This range is quite enough to adjust and maintain the desired temperature. But you can get other power by adding the number of switching modes and using different switching combinations.
A series connection of 2 heating elements of 1.25 kW each and connecting them to a 220V network gives a total of 625 W. A parallel connection gives a total of 2.5 kW.
We know the current voltage in the network, it is 220V. Next, we also know the power of the heating element, knocked out on its surface, let’s say it’s 1.25 kW, which means we need to know the current flowing in this circuit. Knowing the voltage and power, we find out the current strength from the following formula.
Current = power divided by line voltage.
It is written like this: I = P / U.
Where I is the current in amperes.
P - power in watts.
U - voltage in volts.
When calculating, you need to convert the power indicated on the heating element body in kW into watts.
1.25 kW = 1250W. We substitute the known values into this formula and get the current strength.
I = 1250W / 220 = 5.681 A
R = U / I, where
R - resistance in Ohms
U - voltage in volts
I - current in amperes
We substitute the known values into the formula and find out the resistance of 1 heating element.
R = 220 / 5.681 = 38.725 Ohms.
Rtotal = R1+ R2 + R3, etc.
Thus, two series-connected heating elements have a resistance of 77.45 Ohms. Now it is easy to calculate the power released by these two heating elements.
P = U2 / R where,
P - power in watts
R is the total resistance of all sequences. conn. heating elements
P = 624.919 W, rounded to 625 W.
Table 1.1 shows the values for series connection of heating elements.
Table 1.1
|
Number of heating elements |
Power (W) |
Resistance (Ohm) |
Voltage (V) |
Current (A) |
|
Serial connection |
||||
|
2 heating elements = 77.45 |
||||
|
3 heating element =1 16.175 |
||||
|
5 heating element = 193.625 |
||||
|
7 heating element=271.075 |
||||
Table 1.2 shows the values for parallel connection of heating elements.
Table 1.2
|
Number of heating elements |
Power (W) |
Resistance (Ohm) |
Voltage (V) |
Current (A) |
|
Parallel connection |
||||
|
2 heating element = 19.3625 |
||||
|
3 heating element = 12.9083 |
||||
|
4 heating element=9.68125 |
||||
|
6 heating element = 6.45415 |
||||
Greetings, my readers! I decided to write this post for those who are trying to figure out how to connect an electric boiler to the wiring. The article is devoted to heating devices using heating elements as heating elements. I will write about it separately. There are several options for performing this operation, and I will discuss them below in turn. We start, as you may already be accustomed, from simple to complex.
Heating element and single-phase network. What to screw to what?
This case is typical for dachas and old-built village houses. First you need to generally understand what we are talking about and the easiest way to do this is by looking at the following figure:
So, a single-phase electrical network has two conductors - zero and phase. The picture itself shows two ways to turn on the load - parallel and serial. These methods differ in how the initial voltage is divided between the elements. In most cases, heating elements are connected in parallel so as not to lose useful power; a series circuit is suitable only for various specific cases. A block prepared for connection to one phase will look like this:
It is also worth paying attention to the choice of cable, but we will touch on this point a little later, and now let’s move on to the three phases.
Two ways to connect heating elements to three phases.
“Three-phase” used to be something not very necessary and understandable for the common man, but in our time it has become a necessity for a private home. It is needed primarily for heating with electricity. Since an electric boiler has a high power (in most cases more than 6 kW), when using one phase you will need to install cables with a large cross-section of conductors. And this will be expensive, especially if the cable cores are made of copper. In a three-phase network, the cross-sections of the conductors will be noticeably smaller, for this reason most modern electric boilers are connected to a “three-phase” system. Now let's talk about the basic schemes for connecting heating elements to such a network.
Star.
This method is used if the heating element is designed for 220 V. In addition, the “star” requires that the neutral wire be connected from the panel. For clarification, consider the following figure:
In this case, instead of two jumpers there will be one. And it will be connected to zero, and the three remaining free ends will be connected to the corresponding phases. If you look at the block nut from above, it will all look like this: 
Triangle.
This method is used to connect heating elements designed for 380 V. If you suddenly decide to install heating elements designed for 220 V in a “triangle”, they will simply burn out. Don't miss this important moment. The main difference between a “triangle” and a “star” is the absence of a neutral conductor. There are only 3 phases and nothing more. To better understand what we are talking about, look below:
In the picture everything looks simple and clear, but if you start connecting the contacts on the block nut, you will get the following:
It looks a little complicated, but in fact it is no different from the top picture. Colored lines and numbers here indicate the phases, and letters indicate the heating elements of the block.
Summary of the article.
Connecting powerful electric heating devices, such as an electric boiler, is a responsible matter.Mistakes can lead to dire consequences. Up to wiring burnout or fire . Therefore, if you do not have the appropriate skills, thenyou better contact an electrician with the appropriate clearance group . All actions that you are going to do, you do at your own peril and risk. Remember this. That's all, write questions in the comments.
Customs union. Declaration of conformity No. TS RU D-RU.AV98.V.00706
Valid from 12/30/2014. until December 25, 2019
Manufactured according to TU 3443-009-49110786-2002.
Complies with the requirements of technical regulations
Customs Union TR TS 004/2011
Connection diagrams for heating elements (single-phase network)
Tubular electric heaters (TEHs), like other consumers of electricity, are connected to both single-phase and three-phase networks.
When connecting more than one heating element to a single-phase network (1 “phase” and “zero”), parallel, serial or combined connection schemes are used.
1. Parallel connection of heating elements
When connecting in parallel, the following basic laws apply:
- The voltage on each heating element is constant and equal to the network voltage;
- If one of the heating elements fails, the others continue to work;
- The total power of the assembly is the sum of the powers of all heating elements installed in parallel;
- If heating elements of different power are installed in parallel, then the total power is calculated using the formula: P total =U 2 /R total, where P total is the total power, U is the voltage, R total is the total resistance of the assembly. The total resistance of the assembly Rtotal is calculated by the formula: 1/Rtot =1/R 1 +1/R 2 +1/R 3 .
2. Serial connection of heating elements
When connecting in series, the following basic laws apply:
- The total resistance of the assembly is the sum of the resistances of all heating elements installed in series;
- If heating elements of the same resistance are installed in series, then the voltage on each heating element is equal to the total network voltage divided by the number of heating elements in the assembly. In other words: U total =U 1 +U 2 +U 3.
- The total power of the heating element assembly is calculated by the formula P total =U total 2 /R total, where P total is the total power, U total is the total network voltage, R total is the total resistance of the heating element assembly. The total resistance of the assembly Rtot is calculated by the formula: Rtot =R 1 +R 2 +R 3.
- When one heating element fails, the common circuit breaks and the remaining heating elements also stop working.
3. Combined heating element connection
When connecting a heating element in a combined manner, the circuit should be divided into several sections (A and B), for which the laws of either parallel (A) or series (B) connection will apply, respectively.
The voltage value in all diagrams is indicated when connected to the network - 220V.
Connection diagrams for heating elements (three-phase network)
Tubular electric heaters (TEHs), like other consumers of electricity, are connected to both single-phase and three-phase networks. When connecting to a three-phase network (3 “phases” and “zero”), two main connection diagrams are used (“star” and “delta”). In order to distribute the load evenly across phases, the number of connected heating elements should be selected as a multiple of 3.
1. Connection of heating elements - “star”
Basic laws that apply when connecting heating elements with a “star”:
- Between any “phase” and “zero” there is always 220V!
- In each branch of the “star” you can connect several heating elements connected to each other in series or in parallel (see connection diagrams in a single-phase network).
- The power of each branch of the “star” should be the same.
2. Connection of heating elements - “triangle”
Basic laws that apply when connecting heating elements with a “triangle”:
- Between any two “phases” there is always 380V!
- In each branch of the “triangle” you can connect several heating elements connected to each other in series or in parallel (see connection diagrams in a single-phase network).
- The power of each branch of the “triangle” should be the same.
- The total power of the connection is the sum of the powers of the three branches.
The voltage value in all diagrams is indicated when connected to a three-phase network - 380V.
Electric water heating and heating equipment has received great demand among consumers. It allows you to quickly organize heating and hot water supply with minimal initial costs. Some people even create such equipment on their own, with their own hands. A The heart of any homemade device becomes a heating element with a thermostat.
How to choose the right heating element and what to focus on when choosing it? There are quite a lot of parameters:
- Power consumption;
- Sizes and shape;
- Availability of built-in thermostat;
- Availability of corrosion protection.
After reading this review, you will learn how to independently understand heating elements with thermostats and be able to connect them.
Purpose of heating elements
Why do we need heating elements with thermostats? Based on them, autonomous heating systems are designed, boilers and instantaneous water heaters are created. For example, heating elements are mounted directly into batteries, resulting in sections that can operate independently, without a heating boiler. Some models are focused on creating anti-freeze systems - they maintain a low positive temperature, preventing freezing and subsequent rupture of pipes and batteries.
This battery has a built-in heating element with a thermostat, with its help the house is heated.
Storage and instantaneous water heaters are created on the basis of heating elements. Purchasing a boiler is not affordable for every person, so many assemble them themselves using separate components. By installing a heating element with a thermostat into a suitable container, we will get an excellent storage-type water heater - the consumer will only have to equip it with good thermal insulation and connect it to the water supply.
Bulk-type storage water heaters are also being created on the basis of heating elements. In fact, it is a container of water that is filled manually. Heating elements are also built into summer shower tanks, providing water heating to a given temperature in bad weather.
Heating elements for heating water with a thermostat are necessary not only for creating water heating equipment, but also for repairing it - if the heater fails, we buy a new one and replace it. But before that, you need to understand the issues of choice.
Selecting a heating element
When choosing a heating element, you need to pay attention to some details. Only in this case can you count on a successful purchase, high-quality heating, long service life and compatibility of the selected model with a water heating tank, boiler or radiator.
Shape and size
There are dozens of heating element models available for buyers to choose from. They have different shapes - straight, round, figure-eight or ear-shaped, double, triple and many others. When purchasing, you should focus on the use of the heater. For installation in sections of heating radiators, narrow and straight models are used, since the space inside is quite small. When assembling a storage water heater, you should pay attention to the volume and shape of the tank, and based on this, choose a suitable heating element. In principle, almost any model will fit here.
If you need to replace a heating element in an existing water heater, you need to purchase an identical model - only in this case can you count on the fact that it will fit into the tank itself.
Power
If not everything, then a lot depends on power. For example, this could be the heating rate. If you are assembling a small-volume water heater, the recommended power will be 1.5 kW. The same heating element will be able to heat disproportionately large volumes, but it will do this for a very long time - with a power of 2 kW, heating 100-150 liters of water can take 3.5 - 4 hours (not to a boil, but on average by 40 degrees).
If you equip a water heater or water tank with a powerful 5-7 kW heating element, the water will heat up very quickly. But another problem will arise - the house electrical network will not withstand it. When the power of the connected equipment is above 2 kW, it is necessary to lay a separate line from the electrical panel.
Protection against corrosion and scale
When choosing heating elements for heating water with a thermostat, we recommend paying attention to modern models equipped with scale protection. Recently, models with enamel coating have begun to appear on the market. It is this that protects the heaters from salt deposits. The warranty on such heating elements is 15 years. If you don’t find similar models in the store, then we recommend purchasing stainless steel electric heaters - they are more durable and reliable.
The presence of a thermostat
If you are assembling or repairing a boiler or want to equip a heating element with a heating element, choose a model with a built-in thermostat. It will save on electricity by turning on only when the water temperature drops below a set point. If there is no regulator, you will have to monitor the temperature yourself by turning the heating on or off - this is inconvenient, uneconomical and unsafe.
How to connect a heating element with a thermostat
Now you know how and by what parameters heaters are selected. But how is the connection made? In order to connect a heating element with a thermostat, you must select a wire with reliable insulation. We also pay attention to the cross-section - it must be such that the wire can provide adequate power to the heater and not melt. For example, for a 3 kW heater, the wire cross-section must be at least 2.5 mm. We recommend choosing cables with copper conductors for connection.
Do not forget to pay attention to the presence of an RCD - it will instantly turn off the power in the event of an unexpected failure of the heating element or a short circuit. The RCD must be installed as close as possible to the heater itself. You should also ensure a reliable connection of the conductors with the contacts of the heating element (without “snot” and flimsy contacts that can spark).