Calculation of illumination LC

 

New equipment (multiplexers) for communication through fiber optic link between Stepnogorsk and Kokshetau installed in an existing LC. Upon delivery of the building were designed lighting, ventilation and other necessary parts. During prolonged operation times liable to variation. Therefore, questions about the illumination provided below, bears the character of verification of conformity to the norm.

There are general lighting system, a uniform or localized, and the combined lighting system, consisting of general and local lighting.

General lighting is uniform lighting for the premises, or part of the site open area when possible uniform luminance distribution over the entire illuminated area. In this case, generally lamps of a certain type and power are suspended at the same height and are distributed uniformly over the area.

Total localized lighting is used to illuminate the premises, or part of the site open area when consciously attained the uneven distribution of illumination on the area. In this case, type, capacity and height of suspension lamps can be different, and their distribution - uneven.

Local illumination serves only for illumination of the working surfaces. It may be stationary or portable.

The device in the room alone local lighting is prohibited. It must necessarily be supplemented by general lighting that creates a lighting auxiliary areas premises, softens shadows in the workplace and increases the brightness of secondary adaptation fields.

General lighting, arranged in a combined lighting system is usually performed as a uniform. It must be created in the location of jobs and in the last level of illumination zone at least 10% of the rate of the combined light, and not less than 30 lux at filament lamps and 100 lux - with fluorescent lamps. Creating illumination exceeding respectively 100 and 200 lux, not necessarily.

When combined light illumination rates are higher than in the general one. However, even with this combined lighting requires less power than the total, unless the working surfaces are limited in size and are located not too tight.

Uninterrupted operation of the lighting is always desirable, but in some cases it is very necessary, and then, in addition to the usual - "working" - lighting, emergency lighting is arranged. Operating and emergency lighting referred kinds of lighting. Emergency lighting is different in two varieties:

- Emergency lights to continue serving for extinction under emergency lighting conditions of the working vision sufficient for temporary continuation of the staff;

- Emergency lighting for evacuation, which serves to provide for emergency lighting extinction working conditions of vision sufficient to secure release of people from the premises.

Emergency lighting for further work needs to be created on surfaces that require care in an emergency, illumination 5% of the values ​​established for the corresponding normal operation. This light can be uniform, and localized, and local. Emergency lighting for evacuation should create along the lines of the main passages illumination of 0.5 lux. It is performed only as a general or localized uniform. For emergency lighting should, as a rule, use the same light source as the light of the desktop space.

Illumination levels for indoor communication centers take in accordance with the "Instruction on the design of artificial lighting of communication enterprises", as well as regulations.

The light source is recommended to use fluorescent lamps. combined lighting system and adopted mainly for repair of premises, adjustments, cleaning and soldering apparatus and instruments, in other cases, should use a common system (localized or uniform) illumination.

Emergency lighting is required for all major operating communication centers Places (switches, cabinets, crosses). The degree of reliability of power and lighting loads communication nodes defined scheme of power supply enterprise (object) as a whole. On LC lighting powered by induction or AC shield their own needs, or directly from the network operating and emergency lighting of the building, where LC placed. If you have to Battery LC (having usually voltage 60V) lighting emergency lighting completely or partially, depending on the battery capacity, are powered by it, and emergency lighting, powered by a battery, is included with the disappearance of line voltage external sources alternating current.

The main communication rooms provide sockets for a voltage not more than 42V for the connection of portable lighting, soldering irons, drills, and 220 - for measuring instruments, vacuum cleaners, etc.

Modern electronic hardware and software managed and occupy a small area.

The LC installed PC for control, diagnostics and debugging equipment.

To illuminate the room with the mounted PC is used mainly fluorescent lamps, to be used primarily in areas with intense and accurate work and which have the following advantages:

- High luminous efficiency (up to 75 lm / W or more);

- Long service life (10 000 hours);

- Low brightness of the illuminated surface;

- More economical in power consumption;

- Lamp tube surface is heated a little (up to 40 - 50 degrees).

Calculation of lighting will perform the method of utilization of light. Dimensions of distinguishing objects are in the range 1-5 mm, the discharge of the visual work area defined 4th degree of accuracy, so it is economical system of general lighting, where lights are located in the upper zone, which provides uniform illumination of an area of ​​34.72 m2 working space (length - 6.2 m, width - 5.6 meters) and a height of 3 m.

Of the reference data, select the most suitable lamp type LPP02 4'40. This lamp has the following technical data:

- The length of 1,294 m;

- Width of 0.245 m;

- The height of 0,115 m;

- Fully pylezaschischen;

- Type of lamp DTC 40-4.

For lamp DTC 40-4 luminous flux after 100 burning hours will be:

- Nominal 2100 lumens;

- Minimum 1890 lumens;

- The estimated value of 1995 lm.

Based on the calculation of the luminous flux, determine the luminous flux emitted by the lamp:

 

F_cv = 4 ´ 1995 = 7980 lm.

 

The calculation method for the use of luminous flux ratio is calculated as follows:

F = (Е_n ´ К_s ´ S ´ z) / (N ´ h) lm (4.1)

 

Where Е_n - normability illumination, lx.; Ks - the safety factor that takes into account the aging of lamps, luminaires dust and dirt during operation, for building operators halls illuminated by fluorescent lamps and provided cleaning fixtures at least twice a year Ks = 1.5; S - illuminated by floor area in m2; z - illumination non-uniformity coefficient for fluorescent lamps with the location in the line z = 1,1; N - the number of rows of lamps; h - ratio of luminous flux.

The minimum illumination at a total rate of artificial light for this class of our premises is 300 lux, in accordance with SNIP II-4-79 «Natural and artificial lighting. Design standards ";

Since the height of the room does not exceed 3 meters, recommended ceiling mount fixtures. Then the height of the eaves hsv = 0 and the height of the working surface above the floor hp = 0. Thus, the formula of the suspension height:

 

h = H – h_св – h_р = 3-0-0 = 3 m

 

The distance between the rows of lamps is given by:

 

L = l ´ h (m) (4.2)

 

where L - the most advantageous ratio taken for light fixtures with fluorescent lamps K and the curve of 0.6; h - height of suspension.

 

L = 0,6 ´ 3 = 1,8 m.

 

Knowing the distance between rows, we calculate the number of rows. Given that the fixtures will be placed along the long side of the room, the number of rows calculated by the formula:

 

N = B / L (4.3)

 

where B - width of the room, which is equal to 5.6 m.

 

N = 5,6 / 1,8» 3

 

We accept the number of rows of three.

To determine the utilization rate is necessary to find the index premises. space index i is determined by the formula:

 

i = (A ´ B) / h ´ (A + B) (4.4)

 

where A - the room height 6.2 m.; A - the width of the room, 5.6 m.; h - height of suspension, 3 m.

 

i = (6,2 ´ 5,6) / 3 ´ (6,2 + 5,6) = 34,72 / 35,4» 1. (4.5)

 

According to this index space i = 1, we find the reflection coefficients:

Ceiling Rc = 70%, walls Pw = 50%, floor Rf = 10% [6] of Table 5-13 define the ratio of luminous flux of fluorescent lamps:

 

h = 38%.

 

Substituting the resulting value calculation formula in the definition of the luminous flux 19, we get:

 

F = (300 ´ 1,5 ´ 34,72 ´ 1,1) / (3 ´ 0,38) = 17186,4 / 1,14 = 13972,7

 

The required number of fixtures in the series is given by:

 

n = F_рас / F_св (4.6)

 

n = 13972,7 / 7980» 2 lamps.

 

Now define the length of the row of luminaires.

With a length of one lamp type LPP 01 with lamps with a length of 40 MDC lsv = 1,310 m total length will be:

 

L_ov = n ´ l_св (4.7)

 

L_ov = 2 ´ 1,294 = 2,588 м.

 

Possible loss of voltage in the lighting network is determined based on the need to have at the light source voltage is below a certain value.

To calculate the lighting network will take in this case the value of the permissible voltage losses in the grid equal to DU = 2%.

The calculation of the loss of voltage on the network based on a formula:

 

S = M / (C ´ DU) (4.8)

 

where S - the conductor cross-section, mm2; M - load torque, kVt'm; C - constant depending on the voltage, current type and the conduction wire material. In Table 12-9 accept the coefficient C for copper wires with a two-wire AC or DC 220 V DC in equal 7.4.

Moment is determined by the formula:

 

М = n ´ p ´ [l₀ + (l/2 ´ (n – 1))] (kW´m) (4.9)

 

where n - the number of fixtures in a row; l0 - the distance from the panel to the first lamp, m; l - the distance between the mounting fixtures, m; p - the power of one lamp, kW.

 

М = 2 ´ 0,16 ´ [2,5 + (1,3/2 ´ (2 – 1))]=0,32 ´ 3,15 = 1,008 kW´m.

 

We accept wire size in accordance with the standard 2.5 mm2. Recalculated to determine the loss of the supply voltage. From Formula 4.10:

 

DU = M / (C ´ S) (4.10)

 

DU = 1,008 / (7,4 ´ 2,5) = 1,008 / 18,5» 0,06%

 

We have found that the voltage loss in the network is at a rate of 0.06% to 2%.

Thus, to perform the lighting network using copper wire grade SIP (2'0,75) for sockets using wires of the same brand.