It is easier and cheaper to make the heater based on nickel-chromium. Cut length meter self-regulating cable is behind the 330 rubles and up to infinity. Sellers surprisingly consistently forget to specify the system setup temperature, but provides information the power is directly dependent on the conditions, the figure described by the definition in the case of fickle. If we were talking about the resistive cable, the above would make sense. For example, a self-regulating works independently, does not need an incubator. It has a high resilience. So, the fire risk is minimal, happen to make a homemade heater.
Small homemade heater
Heaters and cables
Not everyone've encountered a self-regulating cable, tell a little more about these curious completing defrosting systems, drains buildings. Resistive wire generates heat by Joule-Lenz. The effect is directly proportional to the current, is inversely proportional to the resistance depends on the time of the construction. People to obtain useful heat in the heaters were looking for materials with increased resistance. It seems, it reduces the effect of Joule, but trivial wire can not be connected to 230 V - lived burns. Output short circuit. Try to make the heater with your hands without danger to others.
For example, to obtain a 2 kW heater wire take 28 resistivity ohms. Try to score little piece of copper wire. Nichrome is endowed with significant resistivity of 3-5 meters allow material wound spiral. If you reduce the length of the cut, the power increase, but the situation is not profitable. Conductor characterized some marginal capacity per linear meter, which dissipates. If the value is too high, coil burn. Quickly process will take place in the air.
The first tip is to make the heater:
Study the market for similar structures prefabricated. What power and heater internal arrangement of what materials the product is made.
Then copy specifications. Look in the directory, which linear power dissipates Nichrome. Incidentally, in the technique used fechral from Norway, the composition of the material - a mystery shops do not get it.
What do nichrome. In plants produced from a metal:
Everywhere ability to produce heat used metered (in contrast to copper, wherein the power dissipated per unit length is small, the chance of burn large tube). Unlike tubular electric heaters that spiral compressed powder protected from water and air. The outer copper sheath is used to maintain the shape of the dielectric. This will allow the electrical appliance insulation. Do not forget Nichrome metal, easy to get an electric shock if you do not comply with the precautionary measures.
Self-regulating cable independently monitors the temperature. We would like to inform the readers that resistive cable is made of the ohmic conductor. Not Nichrome and copper.
The composition of the resistive cable is not important, the main thing that generates heat, until the supply voltage is supplied. New technologies have led to the emergence of a dielectric matrix with inclusions of graphite. The concept is the basis of self-regulating cables and expand when the temperature rises. As a result of graphite inclusions cease contact with each other gradually.
In this area the resistance increases. Constant voltage - 220 - means the current drops. Consequently, the reduced Joule effect. Upon cooling area the process is reversed. Self-adjusting matrix is compressed graphite bridges becomes larger, the resistance decreases, the current increases, the thermal effect is enhanced. For the manufacture of the cable is taken two parallel copper wires to supply potential. Between them is laid along the length of self-regulating matrix with graphite inclusions. The beauty of the design is that the pieces will be heated independently. A determining role in the magnitude of the thermal effect plays temperature.
Matrix set in the factory. Most products meet the heating temperature in the low positive temperatures, just above zero. The overwhelming majority of the cables used in the branches defrost structural elements of buildings, and therefore the properties are selected according. Ledkov little grip, the temperature became zero, the matrix is tightened, the cable began to warm. Plus design - no need to control the device. At the same time the resistive cable provides a fixed thermal effect.
If you do not control the process, the temperature rises without limit as long as the cable sheath does not melt, does not start the fire. It is clear that communicate with thermostats do not want: it is difficult and expensive.
Resistive Cable worth a penny, and self-regulated prices have already pointed out. In light of this, we consider that the first is better to use for underfloor heating (but not the ceiling), the second is ideal for unusual designs, such as the heating mats under the seat. Do not forget that you need to hold the insulation correctly. For example, settle between man and cable foil shield, firmly grounded. In this case, the breakdown of bad will happen. Such devices it is better to include the terms of the differential protection device.
Examples improvised heaters
As already noted, it is easier to make the heater nichrome. It needs the segment with a resistance 27 - 28 ohms to get the power of 2 kW. Do not connect such a spiral in parallel. In this case, power is multiplied by the number of heating elements, and in home raspredschitok hruschevke pulls 5 kW. If you do not take into account modern high-rises. The power is calculated using the formula:
N = U2 / R
Heater-vetroduvka own hands
If the resistance of 28 ohms is obtained 1728 W when the voltage effective value of 220 V. It is unlikely to succeed to collect the tubular heater at home, and Nichrome spiral - as much as necessary. To wind the wire rod of ceramics, as is the electric heater, or the plates as in hair dryers or vetroduvkah. Where to get a refractory material. Worth a penny on the market of the capital, on the network to take expensive. Disassemble the old technique and the necessary borrow. Do not use steel winding action will cause unpredictable consequences. Incidentally, in the soldering iron within the insulator of ceramic.
If nothing comes to mind, with the chip brick special hammer (for bricks) and use a thin plate. A fragment of a heavy but reliable. If you find a refractory brick, make better use of heat-resistant. Suitable ceramic tile. Do not forget to make the ends of the plate recess under the wire, shakes in a single layer, not more. In this case violated conditions of heat exchange, Nichrome can burn. By the way, the tile dyryavte special drills (for tiles with a stone on the end). If you intend to forced air cooling, for example, CPU cooler, it will improve the heat transfer.
By the way, fans are not used to increase capacity as it seems. Nichrome little thermal effect depends on the air temperature. Just the wind picks up and the heat will spread quickly around the room. Heating turns poravnomernee. Ceramic tile is mounted by any method acceptable to heat-resistant adhesive (temperature of at least 800 degrees). When heated Nichrome lights and works with infrared heater. If the above is not enough, enter the blowout.
Engines better take on 230 V. Fit asynchronous motors of low power used in extracts or domestic fans. Do not use the collector engines: noisy and sparks. By the way, asynchronous motors procure in the refrigerator, cooker hoods or air conditioning. Avoid linear compressor, no moving parts inside. Homemade heater for the apartment are collected on the basis of a cassette tape recorder. Inside are quiet engines, you need to properly adjust the speed on rewind.
If required to give a home-made heater, collect the burner on the basis of the injector. We describe a similar structure, such popular in the United States. Do not use gasoline to produce heat, vapors are explosive. Not recommended in the heater to blow ionized air through a nozzle, and placed in a perforated tile fire possible. It will serve as a ceramic grid, battery and radiator heat. Simply make a homemade heater is obtained based on the collet tourist balloon. It is necessary to fabricate the nozzle properly, for example, on the basis of the purchase for cooking.