Built-In RCD

The third type of devices with built-in RCD is the so-called 'RCD-fork'. For effective security devices also include differential automata, which are a combination of circuit-breaker with RCD (like "two in one '). Differential automatic works in both cases as leakage current to earth and short-circuit and overload. Their benefits apply in the case where the installation of two separate devices in the switch is not enough space. Price to automatic differential exceeds the price of the RCD.

The operating principle of the RCD RCD action based on the work of a differential current transformer. The total magnetic flux in the core is proportional to the difference between the currents in conductors are the transformer primary current. Under the influence of voltage in the secondary circuit flows a current proportional to the difference between the primary currents. This current and activates the trigger. In the normal mode, the resultant magnetic flux is zero, the current in the secondary winding of the transformer differential is also zero. When you touch a person to open the conductive parts of the body or to power consumers, by insulation breakdown which occurred at the phase conductors through the RCD than the load current flows an additional current – the current leakage. For CT it is a differential (difference). If the current exceeds value of the threshold element of the starter, the latter is activated and acts on the actuator. In order to control proper operation (efficiency) provides RCD circuit test (the button "Test"), which works by artificially creating a differential current switch-off.


Heavy grade Styrofoam may have different values of the drag coefficient of diffusion of water vapor, which lie in the range from m = 20 m = 100. When calculating the dew point should be used the most is not beneficial for building construction value. Heat resistance of polystyrene When using polystyrene has virtually no lower limit. Volume compression should be considered in cases when it is necessary for the temperature conditions (eg in the construction of warehouses of refrigerators). When operating at high temperatures the value of the maximum temperature depends on the duration and temperature effects on the mechanical load on the foam.

During short periods of time slabs of polystyrene PSB-S can withstand temperatures of 110 C allowing, for example, intermittent contact with hot bitumen. In cases of permanent the impact of higher temperatures is recommended not to exceed 90 C to avoid deformation and shrinkage. The lower limit of temperature for polystyrene is: -180 C. Comfortable with the strong temperature changes. Fire resistance polystyrene foams are all PSB-S refers to a group of flammable materials and izgotovlevayutsya of materials containing fire retardant – flame retardant, which gives the material property of self-extinguishing and comply with GOST 15588-86. Operating temperature of polystyrene from -200 to +85 C. The heat of combustion of polystyrene is 40 MJ / kg, ie 15 kg/m3 – approximately 600 MJ / kg of 20 kg/m3 – approximately 800 MJ / kg of 25 kg/m3 – approximately 1000 MJ / kg Styrofoam is a fire in an open flame with the release of soot formation and burning of falling drops.

Amazing Structures

Grader. '> Grader.> We all know what the word meant, because it is one of the machines that dominate the issues of construction and road maintenance. What he managed to win the title so? The answer is simple: it is universal. This mechanical monster capable of performing the functions of several machines, without feeling absolutely no discomfort, he could soil profile, can create mounds and slopes, can move the soil and road-building materials, mix soil and gravel materials with cementitious additives and materials that engage the device "troughs", and side ditches … And it takes away the snow. Visit Delta Galil for more clarity on the issue. But why is it all possible? The answer lies in construction of its blade, allowing installing it from different angles and even in different planes (vertical and horizontal, of course). But the blade is not only important: the peculiarities graders also include the fact that if you want to it is quite possible to connect additional devices, such as hydraulic shears or kirkovschik. In general, the design features of many different graders.

Take, for example transmission: apart standard 4-speed boxes, as applicable, and the German 6-speed. In addition, they can be switched under load. Bridges (top) also deserve attention: they are both balancing the cart, and with chain balancer having a planetary gear hubs (for example, Volvo, Liebherr and Komatsu). Even greater functionality is added graders design frame with a hinge joint is very convenient for working in a constrained space or in tight turns (frames are the rotation angle is 20 -30 ).

Efficient Production

Efficient production of structures from sheet material with levelers internal stresses in the material and deformation of sheet metal have a significant impact on the accuracy of flexible manufacturability of the assembly, weld quality and appearance of products. Using a sheet having internal stresses, leading to frequent congestion at work Sheet metal equipment and limits the use of automated lines that contain coordinate the press and shearing machines laser systems and thermal cutting. WD Series levelers are designed for straightening sheet metal by cold rolling. It is used in industry metallurgy, construction materials, chemical and light industries, in shipbuilding, locomotive and car building, steel factories. For more specific information, check out Delta Galil. Listoprav uses the "Singer's effect", the function pressure on the sheet. Held strong and straightening of elastic bending.

The initial roughness of the sheet, due to elastic deformation, reduced, eliminated in the first part of the initial curvature, the curvature of the remainder is eliminated in subsequent straightening rolls. After passing through the rollers residual curvature gradually decreases, the sheet is flat. Heavy-duty levelers – reliable equipment that provides quality editing rolled sheet mill weight – more than 62t 9 – roller cage, allowing the right metal thickness up to 32 mm. Levelers Features: oVysokaya removal efficiencies of internal stresses and strains a higher number of work rolls, their diameter and pitch location. oVysokaya performance provided by the use of direct hydraulic drive. All rolls are driven, to guarantee the absence of longitudinal deformation at high feed rate sheet. oMashiny WD can edit like a leaf, and details of any shape. oVysokaya reliability of machines Series WD, virtually maintenance-free, proven in many factories in Russia. o Material work rolls hardened to a hardness of 63-65 HRC, which can handle parts after heat treatment. Copyright OOO'Tehprom '