The installation includes the equipped electromagnetic, spring energy storage, manual and other operating mechanisms.
10 earth and stone for direct cable laying in cable trench, with “m ³ Calculation: V ＝ SL, two cables per 1m trench length, V ＝ 0.45M, each additional cable per 1m trench increases by 0.153m ³。 Laying sand cover brick in cable trench: calculated by trench length “m”.
At present, there are three types of domestic fixed, handcart and movable.
8.
TM classification: cooling methods include oil immersion and dry type; The number of phases is divided into single-phase and three-phase; The coil material is divided into copper and aluminum coils; The iron core is divided into hot-rolled and cold-rolled silicon steel sheets.
Here are some official account that are indispensable in the project..
15.
Including the installation of 5.5 ~ 16mm2 electrical connecting jumper wires and grounding wires and grounding terminals between each section of the bridge.
Calculation rules: it shall be measured by control panel, relay panel, analog panel, power supply panel, DC panel, console and box type distribution room respectively.
5.
The power distribution device shall be equipped with circuit breaker (QF), load switch (QL) and disconnector (QS) to disconnect and connect the normal load circuit and protect and control the high-voltage electrical equipment.
Models include GG, GFC, GBC, etc.
Expression of cable length by laying method and position: cable length = (2 × End length + lead up and down length + directly buried length + cable trench length + protective pipe length + steel cable length + wall length + shaft length + bridge length + slot length + ladder length + line length + cable reservation) × (1 + 2.5%) cable ends: fabrication and installation are measured in “PCs”.
Schematic diagram of power and control cables buried in the ground or buried in the trench L = (L1 + L2 + L3 + L4 + L5 + L6 + L7) × (1 + 2.5%) 9 power and control cable installation calculation rules: power and control cables below 10kV; Regardless of the laying method and position, it is calculated as “m”.
Trench masonry: Earthwork Volume “m3”; Bricklaying or pouring “m3” at trench bottom and wall; Trench wall and bottom plastered with cement mortar “M2”; Trench cover plate fabrication “m3”; Purchase value and freight.
Refer to construction project budget quota.
3.
It is generally composed of straight sections, bends, tees and other accessories, supports and hangers.
Calculation rules: whether it is steel, stainless steel, aluminum alloy, glass fiber reinforced plastic or plastic bridge, it shall be calculated according to “m”.
14 the light and dark box wiring (Branch), socket, switch, lamp cap and other boxes of piping wiring shall be measured by “PCs”.
Let’s study together.
Why? From the distinction of cables and wires to the separate calculation, from the electrical bridge to the wall climbing wiring, from the lightning protection grounding to the weak current intellectualization, each link is complex and difficult to understand.
Busbar installation busbar: there are high-voltage busbar of power transformation and distribution device and low-voltage busbar of power distribution in the workshop.
Current transformer (TA) and voltage transformer (TV) are used for measuring voltage, current, electric energy and relay protection.
Common hard bus: copper (TMY) and aluminum (lmy).
TM installation: excluding transformer oil withstand voltage test and transformer system commissioning.
This article will lead you to learn how to calculate the electrical quantities and methods.
When the wires in and out of the cabinet, box and screen need to be welded (pressed) with connection terminals, they shall be measured by “pieces”.
Calculation rule: single piece “extended meter” calculation.
For pipes that can only be laid diagonally, when the drawing scale is correct, the scale can be used for measurement.
Calculation rules for transformer installation: it shall be measured by “units” according to different voltage levels, different capacities and different types.
11 cable trench laid in the cable trench: enter the trench or not.
Pay attention to the difference.
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The conductor reserved length engineer needs to keep forging ahead, learning and further study.
7.
Calculation rules: the above devices are measured by “units”.
4.
Among the installation costs, the most difficult is building electrical.
12 cable tray installation tray: it is divided into ladder type and tray type (perforated tray and non perforated tray).
2.
Method: the horizontal pipe is calculated according to the wall and column axis dimensions in the building plan.
13 rules of piping quantities: the piping shall be calculated according to the material, specification and laying method (light and dark) of the pipe, and shall be calculated according to the “extended meter”, without deducting the length occupied by the junction box (box), lamp cap box and switch box.
Pipe threading length = (pipe length + reserved length of conductor) × Number of conductors in the same section common conductors: single core and multi-core; Aluminum core and copper core; Plastic and rubber insulation.
Electrical wiring rules: lighting and power lines are calculated according to “single line extension meter” regardless of variety, specification, model and laying method.
High voltage and low voltage equipment bases and supports: groove (angle) steel bases and supports shall be calculated according to “kg” and “m”.
Power transformation and distribution devices and equipment shall be calculated in sequence from the household devices.
The suspension insulator XP of 110kV high-voltage overhead household device below 10kV is measured by “string”; Outdoor high-voltage fuse WR below 10kV, measured by “group”; Steel through plate, measured by “block”; CLB through wall conduit below 10kV, measured by “piece”; Lightning arrester FS below 10kV, measured by “group”; Indoor and outdoor support insulators Za below 10kV, measured by “piece”; Supports and fittings are calculated in “kg”.
Remove and cover the cable trench cover plate: “m” calculation; Fabrication and installation of supports in the trench: steel “kg” and concrete “m3”.
L bus = (designed length of single extended meter of bus + reserved length of bus) × (1 + 2.3%) manufacturing and installation loss – 2.3% 6 high voltage control equipment high voltage console, cabinet and screen are used for power plants, industrial and mining enterprises’ power transformation and distribution stations (stations), and the main equipment receiving power and starting and protection of large high voltage AC motors.
Calculation rules for low-voltage control and distribution equipment: complete sets of power, lighting control and distribution cabinets, boxes, panels, etc., regardless of model, specification and installation method, are measured by “units”.
Main points: calculate circuit by circuit from the distribution box.
