How to calculate the project wiring quantity? How to budget?

Friends often ask, how to calculate the amount of work for a wiring project? How to calculate the amount of equipment materials? These problems are often encountered in weak current projects.

Before intelligent engineering, it is important to make adequate budget. So how to budget for intelligent engineering? How to calculate the engineering quantity? This requires mastering the method, and here are some experiences for your reference.

1. Calculation of equipment and materials

1. Calculation of cable:

L = 1.1 × (LMAX (maximum) + LMIN (minimum)) / 2 + 6

among them:

L: is the average amount of line used for each information point.

LMAX: is the distance between the furthest information outlet and the floor management,

LMIN: is the distance between the nearest information outlet and the floor management,

6: End-to-end tolerance (mainly considering factors such as cable loss during construction and cable laying length error), of which 10% is the spare margin.

The number of information points that can be arranged in a box of network cables n=305 / L (n is an integer, and the number after the decimal point is omitted)

Number of cable boxes used in this project:

Number of cable boxes = total number of data points / n*1.1 (considering the loss of wire routing and leaving a certain margin)

Of course , the total cable length can also be used to calculate the number of cable boxes required.

The total number of required cable boxes = the total length of each layer of cable/305 meters * 1.1 (1.1 considers that there is a certain margin)

note:

Total points = data + voice

Another point, please note that the number of network cables is generally about 300 meters, less than 305 meters. If the number of cables for this project is relatively large, this should also be considered. For example, the cable length reserved at the end of the threading equipment should also be considered comprehensively. This will also be judged according to the overall construction process of your construction team.

2. Module calculation: the number of information points;

3. The number of dual-port panels: total points/2;

4. Calculation of 48-port distribution frame:

The total number of points/48, if there are sub-wiring rooms, it should be calculated separately, that is, the number of information points covered by each/48, and then added.

5. Cabinet jumper:

Jump from the patch panel to the jumper of the switch + the cascade line between the switch.

6. RJ45 head:

(Cabinet jumper + workstation jumper) × 2 × 1.1;

7. RJ45 head sheath: the number of RJ45 heads;

8. The number of three types of large logarithms:

The distance from the weak current well to the machine room through the bridge frame + ample amount (larger, because the large logarithm cannot be connected);

9. 110DW2-100FT distribution frame (2U): one is 100 pairs;

10. 110 wire trough: the same as the number of 110 patch panels;

11. 110 backplane (4U):

110DW2-100FT distribution frame quantity/2;

12. 110C4 connection block (10 pcs per pack):

The 110DW2-100FT distribution frame has 100 pairs, that is, 100 phones. It is composed of four parts, each of which is 25 pairs, which is composed of 5 C4 connection blocks and 1 C5 connection block (5×4+1×5= 25), that is, 100 pairs of large logarithms require 20 C4 connection blocks and 4 C5 connection blocks.

13. Telephone jumper (panel/100m): Each telephone jumper needs 1.5 meters.

14. RJ11 head:

Depending on the number of phones, for example, 200 phones (200 pairs of large pairs) need 200 RJ11 heads (the other end is directly connected to the RJ11 distribution frame);

15. How many devices can be placed in a 42U cabinet:

Calculate the height of 48-port patch panels, line managers, RJ11 patch panels, switches, servers, etc. (U);

E.g:

A certain brand of 42U standard cabinet can hold up to 18 sets of 20 servers. Why is there 20? There should be room for heat dissipation between the 1U server and the 1U server. At the same time, a switch should be placed in the cabinet, which also requires 2U space.

If it is a 2U server, you can usually buy about 10, plus you need to place switches, routers and other equipment.

16. When the core equipment room subsystem is optical fiber:

Fiber distribution frame: = number of management rooms * number of fiber cores

Optical fiber jumper (ST-LC): = number of management rooms * number of fiber cores

Pigtail (ST): = number of management rooms * number of fiber cores

Coupler (ST): = number of management rooms * number of fiber cores

2. Calculation method of auxiliary materials

1. Three points to pay attention to when determining auxiliary materials

Statistics information points, including each room and computer room, fill in the point distribution table;

Determine whether it is too long? If it is too long, where should the sub-wiring closets be set up, and how many? If there are sub-wiring closets, the number of switches will change accordingly.

Determine the direction of routing;

2. How to determine the size of the bridge?

E.g:

It is known that the cross-sectional area of ​​the Category 6 network cable is 30.1754mm2. What type of cable tray is suitable for 580 Category 6 cables?

First of all, what is the cross-sectional area of ​​580 category 6 wires?

30.1754mm2*580=17501.73mm2

Since the utilization rate cannot exceed 40%

17501.73mm2/40%=43754.3mm2

Therefore, the total cross-sectional area of ​​the bridge should be greater than 43264.1mm2

So the closest bridge model is 150*300, 200*300, 100*600, etc.

Commonly used standard bridges are: 300×100, 200×100, 100×100, 100×50, 50×50, and other types of bridges can be customized.

3. Calculation of angle steel (30×30):

The length of the angle steel=30cm×(total length of the bridge m/1.5m), that is, the average length of each angle steel is 30cm, and one angle steel is needed every 1.5m distance.

4. Calculation of keel (75×45):

The length of the keel=70cm×(total number of points/2), that is, the length of each keel is 70cm, usually arranged as a double-port panel.

5. Calculation of the bottom box (86×86): the number of the bottom box = generally the total number of points/2

3. Summary: How to calculate the number of cables more accurately

First of all, the number of cables should be calculated according to the construction drawings. We do the construction according to the drawings, and the calculation of drawings is the basis of the entire project budget. Once you have the construction drawings, you should generally compare the orientation of the bridge on the site according to the drawings. Whether it conforms to the design of the drawings, the orientation of the bridge is determined, and the main line is basically determined. The other is to calculate the cables drawn from the bridge frame. The cables drawn from the bridge frame are generally made of pipes. Generally, there are two ways to make pipes: one is for hoisting the cable and the other is for installing along the roof.

The calculation of hoisting construction cables and pipes is relatively straightforward, that is, calculate according to the drawings, and reserve 30cm-100cm at the final equipment end, depending on your final installation equipment and equipment location.

When installing cables and pipes along the roof, you must check whether it is a beam or not. This cannot be calculated according to the drawings. It is necessary to comprehensively consider the conditions of the site construction and calculate the number of cables and pipes.

There is also the calculation of the vertical part and the horizontal part, especially the calculation of the cable in the weak current well. Firstly, it depends on the floor height, and then the distance between the installation position of the weak current well equipment and the bridge frame, comprehensive consideration and comprehensive calculation.