Ansi/tia-862-a pdf download

A note in the text, table, or figure is used for emphasis or for offering informative suggestions. Metric equivalents of US customary units The majority of dimensions in this Standard are metric. Soft conversions from metric to US customary units are provided in parenthesis; e.

Life of this Standard This Standard is a living document. The criteria contained in this Standard are subject to revisions and updating as warranted by advances in building construction techniques and telecommunications technology. The topology proposed in this document is intended to be applicable to any size data center. At the time of publication, the editions indicated were valid.

All standards are subject to revision, and parties to agreements based on this Standard are encouraged to investigate the possibility of applying the most recent editions of the standards published by them. Special definitions that are appropriate to individual technical clauses are also included. Specific requirements are found in the normative clauses of this Standard.

For the purposes of this Standard, the following definitions apply. The information and recommendations are intended to enable an effective implementation of a data center design by identifying the appropriate actions to be taken in each step of the planning and design process. The design specific details are provided in the subsequent clauses and annexes. The steps in the design process described below apply to the design of a new data center or the expansion of an existing data center.

It is essential for either case that the design of the telecommunications cabling system, equipment floor plan, electrical plans, architectural plan, HVAC, security, and lighting systems be coordinated. Ideally, the process should be: a Estimate equipment telecommunications, space, power, and cooling requirements of the data center at full capacity. Anticipate future telecommunications, power, and cooling trends over the lifetime of the data center.

Provide requirements for operations center, loading dock, storage room, staging areas and other support areas. Suggest changes as required. Provide expected power, cooling, and floor loading requirements for equipment to engineers.

Provide requirements for telecommunications pathways. See clause 5 for information concerning the telecommunications spaces within the data center. This Standard addresses telecommunications infrastructure for the data center spaces, which is the computer room and its associated support spaces. Telecommunications cabling and spaces outside of the computer room and its associated support spaces are illustrated in figure 1 to demonstrate their relationships to the data center.

Higher tiers correspond to higher availability and security. Annex G of this Standard provides detailed information for each of the four tiering levels. Therefore, telecommunications and information technology professionals and specifiers should be involved in the design of the data center from its inception. In addition to the space, environmental, adjacency, and operational requirements for the computer and telecommunications equipment, data center designs need to address the requirements of the telecommunications pathways and spaces specified in this Standard.

It depicts the relationship between the elements and how they are configured to create the total system. The basic elements of the data center cabling system structure are the following: a Horizontal cabling subclause 6.

Telecommunications spaces shall be dedicated to support telecommunications cabling and equipment. Depending upon the size of the data center, not all of these spaces may be used within the structure.

These spaces should be planned to provide for growth and transition to evolving technologies. These spaces may or may not be walled off or otherwise separated from the other computer room spaces. The entrance room is the space used for the interface between data center structured cabling system and inter-building cabling, both access provider and customer-owned. This space includes the access provider demarcation hardware and access provider equipment. The entrance room may be located outside the computer room if the data center is in a building that includes general purpose offices or other types of spaces outside the data center.

The entrance room may also be outside the computer room for improved security, as it avoids the need for access provider technicians to enter the computer room. Data centers may have multiple entrance rooms to provide additional redundancy or to avoid exceeding maximum cable lengths for access provider-provisioned circuits.

The entrance room interfaces with the computer room through the main distribution area. The entrance room may be adjacent to or combined with the main distribution area. The main distribution area includes the main cross-connect MC , which is the central point of distribution for the data center structured cabling system and may include horizontal cross- connect HC when equipment areas are served directly from the main distribution area.

This space is inside the computer room; it may be located in a dedicated room in a multi-tenant data center for security. Every data center shall have at least one main distribution area.

The computer room core routers, core LAN switches, core SAN switches, and PBX are often located in the main distribution area, because this space is the hub of the cabling infrastructure for the data center. Access provider provisioning equipment for example the M13 multiplexers is often located in the main distribution area rather than in the entrance room to avoid the need for a second entrance room due to circuit length restrictions.

The main distribution area may serve one or more horizontal distribution areas or equipment distribution areas within the data center and one or more telecommunications rooms located outside the computer room space to support office spaces, operations center and other external support rooms. The horizontal distribution area is used to serve equipment areas when the HC is not located in the main distribution area. Therefore, when used, the horizontal distribution area may include the HC, which is the distribution point for cabling to the equipment distribution areas.

A data center may have computer room spaces located on multiple floors with each floor being serviced by its own HC. A small data center may require no horizontal distribution areas, as the entire computer room may be able to be supported from the main distribution area. However, A typical data center will have several horizontal distribution areas. The equipment distribution area EDA is the space allocated for end equipment, including computer systems and telecommunications equipment.

These areas shall not serve the purposes of an entrance room, main distribution area or horizontal distribution area. There may be an optional interconnection point within the horizontal cabling, called a zone distribution area. This area is located between the horizontal distribution area and the equipment distribution area to allow frequent reconfiguration and flexibility.

Figure 3 illustrates the typical data center topology. The telecommunications room for cabling to the support areas and the entrance room may also be consolidated into the main distribution area in a reduced data center topology. The reduced data center topology for a small data center is illustrated in Figure 4. Circuit distance restrictions may require multiple entrance rooms for very large data centers. Additional entrance rooms may be connected to the main distribution area and horizontal distribution areas that they support using twisted-pair cables, optical fiber cables and coaxial cables.

The data center topology with multiple entrance rooms is shown in figure 5. The primary entrance room shall not have direct connections to horizontal distribution areas. Secondary entrance rooms are permitted to have direct cabling to horizontal distribution areas if the secondary entrance rooms were added to avoid exceeding maximum circuit length restrictions.

Although cabling from the secondary entrance room directly to the HDAs is not common practice or encouraged, it is allowed to meet certain circuit length limitations and redundancy needs. The computer room should meet the NFPA 75 standard. The room shall be located away from sources of electromagnetic interference.

Examples of such noise sources include electrical power supply transformers, motors and generators, x-ray equipment, radio or radar transmitters, and induction sealing devices. The computer room should not have exterior windows, as exterior windows increase heat load and reduce security. Additionally, access to the room shall comply with the requirements of the AHJ. For additional information on monitoring computer room access, see annex G.

Sizing should include projected future as well as present requirements. See annex E regarding guidelines on sizing of computer rooms. Equipment not related to the support of the computer room e.

A minimum of mm 18 in clearance shall be maintained from water sprinkler heads. Finishes should be light in color to enhance room lighting. Floors shall have anti-static properties in accordance with IEC Lighting fixtures should not be powered from the same electrical distribution panel as the telecommunications equipment in the computer room.

Dimmer switches should not be used. Emergency lighting and signs shall be properly placed per authority having jurisdiction AHJ such that an absence of primary lighting will not hamper emergency exit. Doors shall be fitted with locks and have either no center posts or removable center posts to facilitate access for large equipment. Exit requirements for the computer room shall meet the requirements of the AHJ. The minimum distributed floor loading capacity shall be 7.

The floor shall also have a minimum of 1. The recommended hanging capacity of the floor is 2. Proper exit signage shall be placed in accordance with the AHJ.

If the building system cannot assure continuous operation for large equipment applications, a stand-alone unit shall be provided for the computer room.

If the computer room does not have a dedicated standby generator system, the computer room HVAC should be connected to the building standby generator system, if one is installed. The ambient temperature and humidity shall be measured after the equipment is in operation. Measurements shall be done at a distance of 1.

Temperature measurements should be taken at several locations of the air intake of any equipment with potential cooling problems. A positive pressure differential with respect to surrounding areas should be provided. Refer to applicable electrical codes for requirements. A common example of this type of failure would be loosened connections. In these cases, the project structural engineer should be consulted to design safeguards against excessive computer room vibration. The computer room shall have duplex convenience outlets V 20A for power tools, cleaning equipment, and equipment not suitable to plug into equipment cabinet power strips.

The convenience outlets should not be on the same power distribution units PDUs or electrical panels as the electrical circuits used for the telecommunications and computer equipment in the room. The convenience outlets shall be spaced 3. Any generators used should be rated for electronic loads.

If the computer room does not have a dedicated standby generator system, the computer room electrical panels should be connected to the building standby generator system, if one is installed. The power shutdown requirements for computer room equipment are mandated by the AHJ and vary by jurisdiction.

The computer room should have a common bonding network CBN see subclause G. Sprinkler systems in computer rooms should be pre-action systems. Additionally, at least one drain or other means for evacuating water for each m2 ft2 area should be provided.

Any water and drain pipes that run through the room should be located away from and not directly above equipment in the room. It typically houses telecommunications access provider equipment and is the location where access providers typically hand off circuits to the customer.

This hand-off point is called the demarcation point. The entrance room will house entrance pathways, protector blocks for copper-pair entrance cables, termination equipment for access provider cables, access provider equipment, and termination equipment for cabling to the computer room.

The maximum circuit lengths need to include the entire cable route, including patch cords and changes in height between floors and within racks or cabinets. Specific circuit lengths from demarcation point to end equipment to consider when planning entrance room locations are provided in annex A. The entrance rooms may either be located inside or outside the computer room space.

Security concerns may dictate that the entrance rooms are located outside the computer room to avoid the need for access provider technicians to access the computer room.

However, in larger data centers, circuit length concerns may require that the entrance room be located in the computer room. Cabling in the entrance rooms should use the same cable distribution overhead or under floor as used in the computer room; this will minimize cable lengths as it avoids a transition from overhead cable trays to under floor cable trays.

The additional entrance rooms may have their own entrance pathways for dedicated service feeds from the access providers. Alternatively, the additional entrance rooms may be subsidiaries of the primary entrance room, in which case the access provider service feeds come from the primary entrance room. Access and service providers that lease space in the computer room, however, typically require secure access to their spaces.

Outside terminals are typically used when the entrance connection is located in a closure on an outside wall of a building. Inside terminals are used when the outside cable will be connected to the inside distribution cabling system. The space required is related more closely to the number of access providers, number of circuits, and type of circuits to be terminated in the room than to the size of the data center.

Meet with all access providers to determine their initial and future space requirements. See annex C for more information regarding access provider coordination and access provider demarcation. Space should also be provided for campus cabling.

Cables containing metallic components copper-pair, coaxial, optical fiber cables with metallic components etc. The protectors may either be wall-mounted or frame-mounted.

The space for protectors shall be located as close as practical to the point of entrance of the cables into the building. Refer to applicable codes regarding entrance cable and entrance cable termination requirements. Plywood should be either fire-rated fire-retardant or covered with two coats of fire retardant paint.

If fire-rated fire-retardant plywood is to be painted, the paint should not cover the fire-rating stamp until inspection by the fire marshal or other AHJ is complete. Floors shall have anti-static properties as per IEC Emergency lighting and signs shall be properly placed per AHJ such that an absence of primary lighting will not hamper emergency exit. Doors shall be fitted with a lock and have either no center post or a removable center post to facilitate access for large equipment.

Consider having dedicated air-conditioning for the entrance room. If the entrance room has dedicated air-conditioning, temperature control circuits for the entrance room air-conditioning units should be powered from the same PDUs or panel boards that serve the entrance room racks. HVAC for the equipment in the entrance room should have the same degree of redundancy and backup as the HVAC and power for the computer room.

If the building system cannot assure continuous operation, a stand-alone unit shall be provided for the data center entrance room. If the computer room or entrance room does not have a dedicated standby generator system, the entrance room HVAC should be connected to the building standby generator system, if one is installed. Measurement shall be done at a distance of 1.

The quantity of electrical circuits for entrance rooms depends on the requirements of the equipment to be located in the room. The entrance rooms shall use the same electrical backup systems UPS and generators as that used for the computer room. The degree of redundancy for entrance room mechanical and electrical systems shall be the same as that for the computer room. The convenience outlets should not be on the same PDU or electrical panel as the electrical circuits used for the telecommunications and computer equipment in the room.

There shall be at least one duplex outlet on each wall of the room, spaced no more than 4m 12 ft apart, and in floor boxes, poke through and other delivery systems such that they can be reached by a 4. If the computer room or entrance room does not have a dedicated standby generator system, the entrance room electrical panels should be connected to the building standby generator system, if one is installed.

The data center shall have at least one main distribution area. The core routers and core switches for the data center networks are often located in or near the main distribution area. In data centers that are used by multiple organizations, such as Internet data centers and collocation facilities, the main distribution area should be in a secure space. The architectural, mechanical, and electrical requirements for the main distribution area are the same as that for the computer room.

The main distribution area may serve as a horizontal distribution area for nearby equipment or for the entire computer room if the computer room is small. There should be a minimum of one horizontal distribution area per floor. Additional horizontal distribution areas may be required to support equipment beyond the horizontal cable length limitation. The maximum number of connections per horizontal distribution area should be adjusted based on cable tray capacity, leaving room in the cable trays for future cabling.

In data centers that are used by multiple organizations, such as Internet data centers and collocation facilities, the horizontal distribution areas should be in a secure space. The temperature control circuits and air-conditioning units should be powered from a different PDUs or power panels that serve the telecommunications equipment in the horizontal distribution area.

The architectural, mechanical, and electrical requirements for the horizontal distribution area are the same as that for the computer room. Cross-connection shall not be used in the zone distribution area.

No more than one zone distribution area shall be used within the same horizontal cable run. There shall be no active equipment in the zone distribution area with the exception of DC powering equipment. These areas do not include the telecommunications rooms, entrance rooms, main distribution area, and horizontal distribution areas. The end equipment is typically floor standing equipment or equipment mounted in cabinets or racks.

Horizontal cables are terminated in equipment distribution areas on connecting hardware mounted in the cabinets or racks. Sufficient power receptacles and connecting hardware should be provided for each equipment cabinet and rack to minimize patch cord and power cord lengths.

Point-to-point cabling is permitted between equipment located in the equipment distribution area. Cable lengths for point-to-point cabling between equipment in the equipment distribution area should be no greater than 15 m 49 ft and should be between equipment in adjacent racks or cabinets in the same row.

The TR is normally located outside the computer room but, if necessary, it can be combined with the main distribution area or horizontal distribution areas. The data center may support more than one telecommunications room if the areas to be served cannot be supported from a single telecommunications room.

These may include the operation center, support personnel offices, security rooms, electrical rooms, mechanical rooms, storage rooms, equipment staging rooms, and loading docks. The operation center consoles and security consoles will require larger numbers of cables than standard work area requirements.

The quantity should be determined with the assistance of the operations and technical staff. The operation center may also require cabling for large wall-mounted or ceiling-mounted displays e. The electrical rooms, mechanical rooms, storage rooms, equipment staging rooms, and loading docks should have at least one wall phone each.

The electrical and mechanical rooms should also have at least one data connection for access to the facility management system. Cabinets can be equipped with side mounting rails, side panels, a top, and front and rear doors, and are frequently equipped with locks.

If there is an access floor, power distribution cables should be installed here under the access floor on the slab. Equipment that uses the front-to-rear cooling scheme should be used so that it does not disrupt the functioning of hot and cold aisles. Blank panels should be installed in unused rack and cabinet spaces to improve the functioning of "hot" and "cold" aisles. See annex D for additional information regarding coordination of equipment plans with other disciplines.

Cabinets should be aligned with either the front or rear edge along the edge of the floor tile. Racks should be placed such that the threaded rods that secure the racks to the slab will not penetrate an access floor stringer. Dampers or brushes should be installed on floor tile cuts to minimize air loss through openings in the floor tiles.

Floor tile cuts shall have edging or grommets along all cut edges. Floor tile cuts for cabinets should be placed under the cabinets or other location where the floor tile cut will not create a tripping hazard.

Floor tile cuts for racks should be placed either under the vertical cable managers between the racks or under the rack at the opening between the bottom angles. Generally, placing the floor tile cut under the vertical cable managers is preferable as it allows equipment to be located at the bottom of the rack.

Cabinets and racks should be placed at the same location on each floor tile so that floor tile cuts can be standardized. Thus, cabinets should be the same width as the floor tiles and the combined width of one rack and one vertical wire manager should be the same width as the floor tile. Additionally, spacers may be employed between cabinets to ensure that each cabinet in a row starts at the edge of a floor tile. Exceptions to this general rule are: - main distribution area and horizontal distribution area where large vertical cable managers are typically used to provide adequate cable management; - entrance room access provider racks and cabinets, which are often mm 23 in rather than mm 19 in racks; - cabinets for large servers that do not fit in standard mm 19 in cabinets.

Racks that are supported by the access floor shall be bolted to the cement slab or a metal channel secured to the slab by threaded rods that penetrate through the floor tiles. Sharp edges on the top of the threaded rods shall be covered using domed nuts or other method. Exposed threads under the access floor should be covered using split tubing or other method. A front clearance of 1. A minimum of 0. A rear clearance of 1 m 3 ft is preferable.

Some equipment may require service clearances of greater than 1 m 3 ft. Ventilation can be achieved by using: - forced airflow utilizing fans; - utilizing natural airflow between hot and cold aisles through ventilation openings in the front and rear doors of the cabinets; - a combination of both methods. Increasing the size and area of ventilation openings can increase the level of ventilation. For high heat loads, natural airflow is not sufficient and forced airflow is required to provide adequate cooling for all the equipment in the cabinet.

A forced airflow system utilizes a combination of properly placed vents in addition to the cooling fan systems. Airflow from the fans should adequate to dissipate the heat generated in the cabinet. In data centers where the highest availability is desired, fans should be wired from separate circuits than those fed by the PDUs or UPS fed power panels to avoid disruption to telecommunications and computer equipment when fans fail.

Racks and cabinets should preferably be no taller than 2. To ensure adequate airflow and to provide adequate space for power strips and cabling, consider using cabinets that are at least mm 6 in deeper or wider than the deepest.

The rails should provide 42 or more rack units RUs of mounting space. Rails may optionally have markings at rack unit boundaries to simplify positioning of equipment. Active equipment and connecting hardware should be mounted on the rails on rack unit boundaries to most efficiently utilize cabinet space. Similarly, if patch panels are to be installed on the rear of cabinets, the rear rails should be recessed at least mm 4 in.

Patch panels shall not be installed on both the front and rear rails of a cabinet or rack in a manner to prevent service access to the rear of the patch panels. If power strips are to be installed on the front or rear rail of cabinets, adequate clearance should be provided for power cords and power supplies that may be installed on the power strips.

The typical configuration for power strips in cabinets provides at least one 20A, V power strip. The use of two power strips which contain circuits that are fed from diverse power sources should be considered. Power circuits should have dedicated neutral and ground conductors. A number of power strips should be used to provide enough receptacles and current capacity to support the planned equipment.

The plug for the power strip should be a locking plug to prevent accidental disconnection. In addition to the requirements specified in T1. Service providers may install their own equipment in the entrance room in either mm 23 in racks or proprietary cabinets. In the entrance room, main distribution area, and horizontal distribution areas, a vertical cable manager shall be installed between each pair of racks and at both ends of every row of racks.

The vertical cable managers shall be not less than 83 mm 3. Where single racks are installed, the vertical cable managers should be at least mm 6 in wide. Where a row of two or more racks is installed, consider mounting mm 10 in wide vertical cable managers between racks, and mm 6 in wide vertical cable managers at both ends of the row.

The cable managers should extend from the floor to the top of the racks. In the entrance room, main distribution area and horizontal distribution areas, horizontal cable management panels should be installed above and below each patch panel.

The preferred ratio of horizontal cable management to patch panels is Overhead cable tray should not be used for structural support for racks. It is recommended that a structural engineer be consulted in determining appropriate mounting for high weight load applications. The horizontal cabling includes horizontal cables, mechanical terminations, and patch cords or jumpers, and may include a zone outlet or a consolidation point in the zone distribution area.

NOTE: The term "horizontal" is used since typically the cable in this part of the cabling system runs horizontally along the floor s or ceiling s of the data center.

It should also accommodate future equipment and service changes. Consideration should be given to accommodating a diversity of user applications in order to reduce or eliminate the probability of requiring changes to the horizontal cabling as equipment needs evolve.

The horizontal cabling can be accessed for reconfiguration under the access floor or overhead on cable tray systems. However, in a properly planned facility, disturbance of the horizontal cabling should only occur during the addition of new cabling.

Each mechanical termination in the equipment distribution area shall be connected to a horizontal cross-connect in the horizontal distribution area or main cross-connect in the main distribution area via a horizontal cable. Horizontal cabling shall contain no more than one consolidation point in the zone distribution area between the horizontal cross-connect in the horizontal distribution area and the mechanical termination in the equipment distribution area.

Refer to subclause 5. The maximum horizontal distance shall be 90 m ft , independent of media type see figure 7. The maximum channel distance including equipment cords shall be m ft. The maximum cabling distance in a data center not containing a horizontal distribution area shall be m ft for an optical fiber channel including equipment cords, 90 m ft for copper cabling excluding equipment cords and m ft for copper cabling including equipment cords.

If a zone outlet is used, the maximum horizontal distances of copper media shall be reduced in accordance with subclause 6. Additionally, horizontal cable distances in a computer room may need to be reduced to compensate for longer equipment cords in the data center distribution areas. Therefore, careful considerations to the horizontal cable distance should be made to ensure cabling distances and transmission requirements are not exceeded when the equipment cords are attached.

Refer to annex A for additional information on application-based cabling distances. NOTE: For copper cabling, in order to reduce the effect of multiple connections in close proximity on NEXT loss and return loss, the zone distribution area termination should be located at least 15 m 49 ft from the horizontal distribution area termination. D is a de-rating factor for the patch cord type 0.

Z is the maximum length m of the zone area cable. T is the total length of patch and equipment cords. The zone outlet shall be marked with the maximum allowable zone area cable length. One method to accomplish this is to evaluate cable length markings.

This Standard specifies transmission media, which shall be used individually or in combination in the horizontal cabling. These cables and connectors are recommended to support specific applications per annex A. NOTES 1 Crosstalk between individual, unshielded twisted-pairs may affect the transmission performance of multipair copper cables. Backbone cabling consists of the backbone cables, main cross-connects, horizontal cross- connects, mechanical terminations, and patch cord or jumpers used for backbone-to-backbone cross-connection.

The backbone cabling is expected to serve the needs of the data center occupants for one or several planning phases, each phase spanning a time scale that may be on the order of days or months. During each planning period, the backbone cabling design should accommodate growth and changes in service requirements without the installation of additional cabling. The length of the planning period is ultimately dependent on the design logistics including material procurement, transportation, installation and specification control.

The backbone cabling shall allow network reconfiguration and future growth without disturbance of the backbone cabling. The backbone cabling should support different connectivity requirements, including both the network and physical console connectivity such as local area networks, wide area networks, storage area networks, computer channels, and equipment console connections.

There shall be no more than one hierarchical level of cross- connect in the backbone cabling. From the horizontal cross-connect, no more than one cross- connect shall be passed through to reach another horizontal cross-connect. When the horizontal cross- connects are not used, the cabling extending from the main cross-connect to the mechanical termination in the equipment distribution area is considered horizontal cabling.

If the horizontal cabling passes through the HDA, sufficient cable slack shall exist in the horizontal distribution area to allow movement of the cables when migrating to a cross-connect.

Backbone cabling cross-connects may be located in telecommunications rooms, equipment rooms, main distribution areas, horizontal distribution areas or at entrance rooms. Intelligent building systems include control systems such as security and monitoring i. The distinct advantage of being able to support multi-product and multi-vendor environments can be realized if these systems, especially those that rely Internet Protocol IP communication between devices, are deployed over the same generic structured cabling topology used for telecommunications applications.

Specific content addresses recommended cabling topology, architecture, design and installation practices, test procedures, and components. Significant changes from the previous edition include:. Click here for answers to common category 8 cabling questions. Means, Inc. Active Only. Complete Document. Includes all amendments and changes through Addendum 1, October 27, Detail Summary View all details. Price USD. Secure PDF. In Stock. Need it fast?

Ask for rush delivery. Most backordered items can be rushed in from the publisher in as little as 24 hours. Some rush fees may apply. Add to Cart. The cabling infrastructure specified by this Standard is intended to support a wide range of systems, particularly those that utilize or can utilize IP-based infrastructure.

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