Types of telecommunication cabinets

Our company Maltima Telecom has been engaged in the selection and supply of telecommunications equipment since 2000. Freely orienting ourselves in the entire range of telecommunications equipment, we are regularly faced with the need to explain one or another basic principles of equipment selection for specific projects time after time. In this regard, we decided to publish a number of reference materials that could help customers quickly make the best choice of product positions for their specific tasks.

Telecommunications cabinet (TS) is an integral element of any structured cabling systems (SCS) and data centers (DPC). The range of such products is huge, and the wrong choice of a particular model can often lead to a wide variety of undesirable consequences, among which equipment failures constitute only a fraction.
In order to choose the right TS at the design stage of the SCS / DPC, it is necessary to have a general idea of ​​what qualities it should possess. There are at least five of these qualities: compliance with the standard (usually ANSI / EIA RS-310 D), sufficient capacity (maximum number of units, width, depth), equipment protection from climatic factors, ability to maintain temperature and humidity conditions, protection from unauthorized access.
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Ideally, of course, I would like all cabinets to meet all the above requirements, but this approach is not optimal and only leads to inflating the project budget. Therefore, the best strategy when choosing a specific model of cabinets for SCS / data center is the principle of necessary sufficiency. Consider the main types of "19-inch" telecommunication cabinets with an emphasis on their strengths and weaknesses in terms of operating conditions.

Capacity

Despite the fact that the distance between the rails in the “19-inch” cabinet is standardized, its overall width is usually 600 or 800 mm. Despite the fact that, due to its compactness, it is precisely 600-millimeter cabinets that are most widely used, 800-millimeter cabinets also do not lose relevance. This is due to the fact that they are better suited for mounting a large number of cables due to the additional space between the guides and the outer wall.

Depth TSH varies widely, the maximum today is 1300 mm. When choosing a particular cabinet model, it should be noted that the recommended distance from the equipment placed in it to the rear wall is 150 mm. This is quite enough for ventilation, comfortable installation and prevention of excessive bending of cables.

Speaking of capacity, we should mention the division of TSH on the floor and wall. The latter are often more convenient, but they have a number of limitations. For example, their capacity is usually limited to 22U, and the depth does not exceed 600 mm. If these parameters do not meet the requirements of the project, you should stop at the floor TS, which can hold up to 48U with a maximum depth of 1300 mm.


Floor cabinet 19 "TTC-4782-SR-RAL9004 47U 800x1200

When choosing the capacity of the TS, one should take into account not only the current, but also the future needs in the capacity of the SCS / DPC. The number of units in the TSH in the future may increase, sometimes many times, in addition, the current and future needs of the main equipment for auxiliary elements, such as fan panels, power outlets, etc., should be estimated in advance.

Climatic factors, mode of operation

Most telecommunication cabinets are designed for indoor installation with constantly controlled temperature and humidity parameters. Because of this, their protection complies with IP20 or IP21 (Type 1 and Type 2 according to the NEMA classification), which means preventing equipment from contacting solids with a diameter of more than 12.5 mm (including human fingers), but does not regulate the possibility of moisture penetration. (IP21 standard nevertheless implies protection against vertically falling individual drops). Of course, the lack of protection from dust and moisture significantly reduces the cost of the TS, but for complete confidence in the right choice, you should make sure that the room completely excludes the possibility of even short-term condensation (for example, when the central heating is temporarily disconnected during the winter period).

In some cases, the IP20 standard does not meet the requirements imposed by the operating conditions of the equipment. Then you should pay attention to more protected TSh certified in IP55, IP65 or IP66 protection classes (Type 4, 4X according to the NEMA classification). They are designed to accommodate autonomously functioning active and passive telecommunications equipment and provide complete protection from environmental influences. When choosing such TS, one should pay attention to the presence of plugs with a seal at the cable entry points, an internal heat insulating coating for the case, as well as a mounting panel for installation of microclimate maintenance devices, such as heaters, thermal switches, hygrostats, etc.


Case street all-weather wall ShTV-N-18.6.5-4AAA

Access control

Cases of unauthorized access to the contents of a telecommunications cabinet can be divided into two types: unauthorized access and vandalism. To prevent incidents of the first type, it is usually sufficient to choose a TS with doors fitted with locks. In this case, access control will be ensured by the presence of a key from one or another TSH only by an authorized officer of the operations department. Also in this case there is no restriction on the use of TS with glass doors, unless otherwise specified by the current security regime.

In places with free access, if there is a risk of vandalism or deliberate damage to the TSH and the equipment contained in it, the requirements for protective properties are the most stringent. They must ensure the impossibility of violating the integrity of the TSH without the use of metal-cutting tools. This is usually achieved through the use of internal door hinges (to prevent cutting), thick steel walls (1.2–3.0 mm), internal steel frame and mechanical damage resistant locks. Holes for mounting such a cabinet should be located inside its volume.


Anti-vandal case of the penny ShRN-A-6.500 type

How cabinets are tested before they go on sale

Especially for this material, we asked the manufacturers to comment on how the telecommunication cabinets are tested before they go on sale. First, the production of cabinets itself is checked: the expert group evaluates the production process. Further, the expert in metal processing, on finished products, evaluates the quality of the metal, painting, assembly, and size. Such specialists are real professionals: by the way the profiles at the cabinet are bent, they can determine the quality of the metal and the assembly of the cabinet. The next step is a special team of installers checks the ease of assembly of the cabinet, i.e. how simple and easy it will be for the user to assemble the product in place. Further, the convenience of installation of additional equipment in the cabinet (shelves, fans, organizers, etc.) is being tested. And finally, the last stage is the verification of the stated load capacity, i.e. If it is stated that the cabinet can withstand 1.5 tons, it loads test equipment with 1.5 tons and with special markers it is monitored how the product can withstand the load.

Of course, in the framework of a small article it is impossible to consider all the details that should be considered when choosing telecommunication cabinets for specific tasks. However, using this material as a map, you can quickly navigate the variety of solutions on the market and focus on the niche that most accurately meets the task. It is important to keep in mind the already mentioned principle of necessary sufficiency.