Spatial Requirements
GR-63-COREIssue 3, March 2006
Figure2-11 Typical Cable Pathways for a Distributing Frame Area
1219 mm (4’ - 0\762 mm (2’ - 6\
Cross Aisle Pathways (1 981 mm Centers)80% Terminating via Cabling 20% System Cabling
6.1 m
(20’ - 0\
Columns
Term & Through via and SystemCross Aisle Pathways
Light
Terminating via& System Lineup Pathway
DFDF
2.6 Operations Systems (OSs)
OSs assist in maintenance, operations, administration, and record-keeping. Many of the OSs use minicomputers and general-purpose computers. OSs can have either a single-site or distributed configuration. They may be located in switching and transmission equipment frame areas, in separate areas or rooms, or in both.
R2-45[38] OS facilities located in equipment frame areas shall be subject to the spatial and
weight requirements outlined in Section2.1 and Section2.2. They also shall be capable of operating in the various environments that Section4, “Environmental Criteria,” specifies.
2–22
2438 mm (8’-0\)2540 mm (8’-4\)2845 mm(9 -4\)406 mm (16\ Min.
3048 mm to Clear Ceiling
NEBSTM Requirements: Physical ProtectionGR-63-CORE
Spatial Requirements
2.7 Cable Entrance Facility (CEF)
The CEF is the interface between the network and the Outside Plant (OSP) network. The CEF provides space for the entrance, splicing, bridging, pressurization, and routing of various cables. The three types of CEFs are: above-surface, subsurface, and a combination of above-surface and subsurface, called the duplex CEF. A
duplex CEF typically is used when the MDF is on an upper floor of a building. Each of these CEFs may be either enclosed by walls, partitions, etc., for fire and
contamination protection, or unenclosed and thus part of the same environment as the adjacent equipment. The CEF system should be designed to adhere to the building and equipment requirements.
2.7.1 CEF Spatial Requirements
O2-46[39] Designs for the CEF should be compatible with the spatial requirements of the
network, i.e., a 3048-mm (10-ft) clear height for equipment and associated cabling, and 3810 mm (12 ft, 6 in) for the lowest building structural member.
2.7.2 CEF Loading Requirements
O2-47[40] CEF equipment should have a maximum floor load of 700 kg/m2 (143.4 lb/ft2).
This applies to floor-supported equipment, and is determined by totaling the weight of all such equipment in the area, including cable, splice cases, and racks, and dividing by the associated floor area. The total weight may be averaged over the entire cable entrance area, including aisles and personnel work areas. The weight of all such equipment should be supported by the floor. R2-48[41] Wall-supported CEF equipment shall have a 375-kg/m2 (76.8-lb/ft2) maximum
weight allowance. The uniform weight allocation is the total weight of CEF equipment divided by the surface area of the wall over which the equipment is placed. The center of gravity of any such wall-supported equipment shall be 406 mm (16 in) or less from the surface of the wall (measured perpendicular to the wall). Otherwise, the 375-kg/m2 (76.8-lb/ft2) weight allocation shall be proportionately decreased.
2.7.3 CEF Equipment Temperature and Humidity Requirements
R2-49[42] Equipment installed in unenclosed above-surface CEFs that are adjacent to the
network shall meet the thermal requirements specified in Section4.1, “Temperature, Humidity, and Altitude Criteria.”
NOTE: Enclosed CEFs and unenclosed subsurface CEFs may not have
permanent facilities for heating. These facilities may be subjected to low temperatures and moisture conditions outside the requirements of
2–23
Spatial Requirements
GR-63-COREIssue 3, March 2006
Section4.1. In an enclosed CEF, these conditions may be controlled by installing a mechanical ventilation system to provide continuous air flow from an air-conditioned part of the building.
2.8 Summary of Equipment Allocations
Table2-2 summarizes equipment vertical space and floor load allocations.
Table2-2 Summary of Equipment Space and Load Allocations
Equipment
Vertical Space
Floor Load
Equipment Frame Area ?Frames
?CDS
Power Area - All equipment cabling, bus bars, lights, and installation clearances
Distributing Frame Area
Floor to 3048 mm(Floor to 10 ft)Floor to 3048 mm(Floor to 10 ft) Floor to 3048 mm(Floor to 10 ft)
560 kg/m2 (114.7 lb/ft2)125 kg/m2 (25.6 lb/ft2) 700 kg/m2 (143.4 lb/ft2)
and installation clearances (Floor to 9 ft)
2743 to 3048 mm?Via cabling
(9 to 10 ft)
CEF - All equipment, cable, and Floor to 3048 mminstallation clearances (Floor to 10 ft)Transient Loads---
?Equipment, cabling, lights, Floor to 2743 mm
675 kg/m2
(138.3 lb/ft2)25 kg/m2 (5.1 lb/ft2)700 kg/m2 (143.4 lb/ft2)50 kg/m2 (10.2 lb/ft2)
2–24
NEBSTM Requirements: Physical ProtectionGR-63-CORE
NEBS-2000 Framework Criteria
3 NEBS-2000 Framework Criteria
The information in this section has been deleted in GR-63-CORE, Issue 3. This
encompasses the removal of Requirements R3-1 [43] through R3-24 [66]. Please refer to ANSI T1.336-2003, Engineering Requirements for a Universal Telecom
Framework for dimensional, performance, and application criteria that may be applied to framework used to support electronic equipment shelves in a
telecommunications facility. The ANSI T1.336-2003 criteria may be used in place of the traditional frame dimensions of standard EIA-310-D, Cabinets, Racks, Panels, and Associated Equipment.
3–1
NEBS-2000 Framework Criteria
GR-63-COREIssue 3, March 2006
3–2
NEBSTM Requirements: Physical
Protection
(A Module of LSSGR, FR-64; TSGR, FR-440; and NEBSFR, FR-2063)
Telcordia Technologies Generic Requirements
GR-63-COREIssue 3, March 2006
Comments Requested (See Preface)
Copyright Page
GR-63-COREIssue 3, March 2006
NEBSTM Requirements: Physical Protection
Prepared for Telcordia Technologies, Inc. by: Network Infrastructure and Operations.This document replaces: GR-63-CORE, Issue 2, April 2002.
This document is a module of LSSGR, FR-64; TSGR, FR-440; and NEBSFR, FR-2063.
Where major additions or technical changes have occurred in Issue 3, the location of the change is marked by a vertical bar (|) in the outer margin next to the change.Technical contact:
Richard Kluge, DirectorTelcordia — GR-63-CORE
One Telcordia Drive, Room 4D-660 Piscataway, NJ 08854-4182 Phone: + 1.732.699.5490FAX: + 1.732.336.3235
E-Mail: rkluge@telcordia.com
To obtain copies of this document, contact your company’s document coordinator or your Telcordia account manager, or call 1.866.672.6997 (USA) or + 1.732.699.6700 (Worldwide), or visit our Web site at http://telecom-info.telcordia.com. Copyright ? 1995, 2002, 2006 Telcordia Technologies, Inc. All rights reserved.
Trademark Acknowledgments
Telcordia is a registered trademark and NEBS is a trademark of Telcordia Technologies, Inc.All other brand or product names are trademarks of their respective companies or organizations.
ii
NEBSTM Requirements: Physical ProtectionGR-63-CORE
Generic Requirements Notice of Disclaimer
Generic Requirements Notice of Disclaimer
This Generic Requirements document (GR) is published by Telcordia Technologies to inform the industry of the Telcordia view of proposed generic requirements for NEBSTM Requirements: Physical Protection. The generic requirements contained herein are subject to review and change, and superseding generic requirements regarding this subject may differ from those in this document. Telcordia reserves the right to revise this document for any reason (consistent with applicable provisions of the Telecommunications Act of 1996 and applicable FCC rules).
TELCORDIA AND THE OTHER PARTICIPANTS IDENTIFIED IN THE PREFACE MAKE NO REPRESENTATION OR WARRANTY, EXPRESSED OR IMPLIED, WITH RESPECT TO THE SUFFICIENCY, ACCURACY, OR UTILITY OF ANY INFORMATION OR OPINION CONTAINED HEREIN.
TELCORDIA AND THE OTHER PARTICIPANTS EXPRESSLY ADVISE THAT ANY USE OF OR RELIANCE UPON SAID INFORMATION OR OPINION IS AT THE RISK OF THE USER AND THAT NEITHER TELCORDIA NOR ANY OTHER
PARTICIPANT SHALL BE LIABLE FOR ANY DAMAGE OR INJURY INCURRED BY ANY PERSON ARISING OUT OF THE SUFFICIENCY, ACCURACY, OR UTILITY OF ANY INFORMATION OR OPINION CONTAINED HEREIN.
LOCAL CONDITIONS MAY GIVE RISE TO A NEED FOR ADDITIONAL
PROFESSIONAL INVESTIGATIONS, MODIFICATIONS, OR SAFEGUARDS TO MEET SITE, EQUIPMENT, ENVIRONMENTAL SAFETY OR COMPANY-SPECIFIC REQUIREMENTS. IN NO EVENT IS THIS INFORMATION INTENDED TO
REPLACE FEDERAL, STATE, LOCAL, OR OTHER APPLICABLE CODES, LAWS, OR REGULATIONS. SPECIFIC APPLICATIONS WILL CONTAIN VARIABLES UNKNOWN TO OR BEYOND THE CONTROL OF TELCORDIA. AS A RESULT, TELCORDIA CANNOT WARRANT THAT THE APPLICATION OF THIS INFORMATION WILL PRODUCE THE TECHNICAL RESULT OR SAFETY ORIGINALLY INTENDED.
This GR is not to be construed as a suggestion to anyone to modify or change any product or service, nor does this GR represent any commitment by anyone,
including but not limited to Telcordia and the other participants in the development of this Telcordia GR, to purchase, manufacture, or sell any product with the described characteristics.
Readers are specifically advised that any entity may have needs, specifications, or requirements different from the generic descriptions herein. Therefore, anyone wishing to know any entity’s needs, specifications, or requirements should communicate directly with that entity.
Nothing contained herein shall be construed as conferring by implication, estoppel, or otherwise any license or right under any patent, whether or not the use of any information herein necessarily employs an invention of any existing or later issued patent.
TELCORDIA DOES NOT HEREBY RECOMMEND, APPROVE, CERTIFY,
WARRANT, GUARANTEE, OR ENDORSE ANY PRODUCTS, PROCESSES, OR SERVICES, AND NOTHING CONTAINED HEREIN IS INTENDED OR SHOULD BE UNDERSTOOD AS ANY SUCH RECOMMENDATION, APPROVAL,
CERTIFICATION, WARRANTY, GUARANTY, OR ENDORSEMENT TO ANYONE.
iii
Generic Requirements Notice of Disclaimer
GR-63-COREIssue 3, March 2006
For general information about this or any other Telcordia documents, please contact:
Telcordia Customer Service
One Telcordia Drive, Room 1B-180Piscataway, NJ 08854-41821.866.672.6997 (USA)
+ 1.732.699.6700 (Worldwide)+ 1.732.336.2226 (FAX)
e-mail: document-info@telcordia.com
web site: http://telecom-info.telcordia.com
iv
NEBSTM Requirements: Physical ProtectionGR-63-CORE
Table of Contents
Table of Contents
1Introduction
1.11.21.31.4
Purpose and Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–1Service Provider Role. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–1Equipment Manufacturer Role. . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–2Application Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–31.4.1COs and Similar Facilities . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–31.4.2Commercial Buildings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–31.4.3Non-Environmentally Controlled Locations . . . . . . . . . . . . . . . . . 1–31.4.4Other Locations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–3Reasons for GR-63-CORE, Issue 3. . . . . . . . . . . . . . . . . . . . . . . . . . 1–4Structure and Use of This Document . . . . . . . . . . . . . . . . . . . . . . . . 1–4Related Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–5Requirements Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–5Requirement Labeling Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 1–61.9.1Numbering of Requirement and Related Objects . . . . . . . . . . . . . . 1–61.9.2Requirement, Conditional Requirement, and Objective Identification. . . 1–7
1.51.61.71.81.9
2Spatial Requirements
2.1General Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–1
2.1.1Equipment Frame Floor Plans. . . . . . . . . . . . . . . . . . . . . . . . . 2–32.1.2NEBS Data (ND) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–32.2Equipment Frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–6
2.2.1Vertical Space Allocation in an Equipment Frame Area . . . . . . . . . . 2–62.2.2Equipment Frame Dimensions . . . . . . . . . . . . . . . . . . . . . . . . 2–7
2.2.2.1Equipment Frame Dimensions - Open Style Racks . . . . . . . . . . 2–92.2.2.2Equipment Frame Dimensions - Other Rack Styles . . . . . . . . . . 2–92.2.2.3Equipment Frame Dimensions - Special Cases . . . . . . . . . . . 2–102.2.2.4Equipment Frame Cable Management Provisions. . . . . . . . . . 2–112.2.2.5Equipment Frame Interface with Cable Rack . . . . . . . . . . . . 2–112.2.3Equipment Frame Lineup Conformity . . . . . . . . . . . . . . . . . . . 2–122.2.4Equipment Frame Floor Loading . . . . . . . . . . . . . . . . . . . . . . 2–122.2.5AC Convenience Outlets Within Equipment Frames . . . . . . . . . . . 2–142.3Distributing and Interconnecting Frames. . . . . . . . . . . . . . . . . . . . . 2–14
2.3.1Distributing Frames (DFs). . . . . . . . . . . . . . . . . . . . . . . . . . 2–142.3.2Interconnecting Frames (IFs) . . . . . . . . . . . . . . . . . . . . . . . . 2–152.4DC Power Plant Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–16
2.4.1Centralized DC Power Plant Equipment . . . . . . . . . . . . . . . . . . 2–162.5Cable Distribution Systems (CDSs) . . . . . . . . . . . . . . . . . . . . . . . . 2–17
2.5.1CDS Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–18
2.5.1.1General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–182.5.1.2Overhead Cable Distribution . . . . . . . . . . . . . . . . . . . . . 2–182.5.1.3Cable Distribution Under Raised Floor. . . . . . . . . . . . . . . . 2–182.5.2Cable Pathways Over Equipment Frame Areas . . . . . . . . . . . . . . 2–19
2.5.2.1Elements of Allocation Plan. . . . . . . . . . . . . . . . . . . . . . 2–192.5.2.2System Cable Racks . . . . . . . . . . . . . . . . . . . . . . . . . . 2–202.5.2.3Via Cable Racks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–21
v
NEBSTM Requirements: Physical ProtectionGR-63-CORE
Spatial Requirements
R2-33[26] This requirement has been superseded by R2-10 [146]in Issue 3.
O2-34[27] Equipment frames should be capable of being installed on building floor
structures having a total floor load capacity of 735 kg/m2 (150. 6 lb/ft2). Centralized dc power plant frames are allocated 700 kg/m2 (143.4 lb/ft2) with 50 kg/m2 (10.2 lb/ft2) allocated for transient loads (see Section2.2).
System design considerations and individual site characteristics (e.g., base slab installations or existing high-capacity floor structures) may justify the use of floor loadings greater than 700 kg/m2 (143.4 lb/ft2) for centralized dc power plant equipment. A frame that exceeds the 700 kg/m2 requirement is designated a concentrated load and may require site-specific engineering.
O2-35[28] Centralized dc power plant equipment should support all overhead CDSs, bus
bars, and lights. In partially equipped areas, these elements may be supported by floor-mounted stanchions. Centralized dc power plant equipment shall be
designated for base-mounted attachment to the floor without auxiliary support or bracing from the ceiling or side walls. When so supported, centralized dc power plant equipment shall be capable of withstanding the network environments, including the earthquake environments, that Section4, “Environmental Criteria,” describes.
Lineup or Frame-Mounted DC Power Equipment — dc power plant equipment units that can be installed in equipment frame lineups as Section2.1 and Section2.2 discuss. The criteria in Section2.1 and Section2.2 apply to line-up dc power equipment.
2.5 Cable Distribution Systems (CDSs)
CDSs consist of cable, racks, and supports and are grouped into two categories:
?System CDSs — CDSs designed for exclusive use with, and dedicated to, a
particular equipment system. They are used for cabling frames within a system. In this context, system means a number of frames and associated cables, all with a single major function.
particular equipment system and passes over it, or terminates in it. Via racks include vertical cable runs in multi-story facilities. They usually consist of ladder or bar-type racks.
?Via CDSs — CDSs designed to transport cable that originates outside a
2–17
Spatial Requirements
GR-63-COREIssue 3, March 2006
2.5.1 CDS Requirements2.5.1.1 General
CDSs shall conform to the earthquake and office vibration requirements of Section4.4, “Earthquake, Office Vibration, and Transportation Vibration.”
2.5.1.2 Overhead Cable Distribution
The CDS should provide cable pathways that are located, sized, and allocated to meet the requirements of Section2.5.2, “Cable Pathways Over Equipment Frame Areas,” as appropriate.
O2-36[29] At least one (1) cross-aisle pathway per building bay should be reserved for via
cabling.O2-37[30] System and via lineup racks should be centered over the equipment lineups to
minimize interference with installer access, and air and light distribution in the aisles.O2-38[31] System CDSs should be supported by the associated equipment frames/
cabinets, or by stanchions in partially equipped lineups, with provision for inserting or removing frames/cabinets from a lineup. Via CDSs may be supported by the frames/cabinets or from the ceiling.O2-39[32] System CDSs should be coordinated with frame-and-aisle lighting so the
system conforms to the illumination requirements of Section4.7, “Illumination.”O2-40[33] System CDSs should provide adequate clearance for transporting frames in an
erected position through the maintenance aisle.
2.5.1.3 Cable Distribution Under Raised Floor
Some designs may provide an option for system cabling to be installed under a raised floor. In this case, overhead space allocations for system CDSs may be traded for space under the floor. Requirements for overhead via CDSs do not change.
R2-41[34] Cabling under the raised floor shall conform to the requirements of the NEC
and applicable state and local codes.R2-42[35] The underfloor CDS shall provide for monitoring with smoke detectors and for
protecting the cables against malfunctions caused by water leaks and dampness.
2–18
NEBSTM Requirements: Physical ProtectionGR-63-CORE
Spatial Requirements
O2-43[36] Communication cables should be segregated from power cables to avoid
physical damage and electrical interference.
2.5.2 Cable Pathways Over Equipment Frame Areas
Above 2134-mm (7-ft) high equipment, the 2134-mm to 3048-mm (7-ft to 10-ft) cable pathways space is typically allocated between system and via cable racks, lights, passages for cooling air, and installer access. This section specifies the plan for allocating cable pathways.
2.5.2.1 Elements of Allocation Plan
The cable pathway plan coordinates the locations of elements of the equipment-building system, including the structural columns, cable holes, ceiling inserts, cooling air ducts and diffusers, smoke detectors, equipment frame lineups, cable racks, and equipment aisle lighting. Specifically, the plan provides system and via cable pathways at different levels, both parallel and perpendicular to equipment frame lineups. It creates large unobstructed openings between cross-aisle pathways. The pathways permit cooling air to flow down to equipment from or above the 3048-mm (10-ft) level, and provide good access to all cable racks. The plan ensures vertical cable holes are not blocked by cable pathways, and lights are placed in an ideal location. The air flow from the top of the equipment frames should not be blocked by cable trays, lighting fixtures, or other large impediments.
Figure2-10 shows a typical plan for 305-mm (12-in) deep frames. This plan can be adjusted to work in buildings with different column and cable-hole spacings. Cable pathways dedicate the various spaces during the life of the equipment-building system.
2–19
Spatial Requirements
GR-63-COREIssue 3, March 2006
Figure2-10 Typical Cable Pathways for 305-mm (12-in) Deep Frame Areas
(Conventional Cooling System - Air Diffusers)
Cross Aisle Pathways 75% System Cabling 25% via Cabling 762 mm (2’ - 6\1524 mm(5’) 6.1 m(20’ - 0\ 457 mm (18\610 mm(2’ Min)Wiring AisleColumnsMaintenance Aisle FireDetector406 mm(1’-4\ Lineup via Cable Pathway Air Diffuser Lineup System Cable PathwaySystem & via Cross Aisle PathwayEquipment Frames Light2.5.2.2 System Cable Racks
System cable racks running parallel to equipment lineups typically occupy the space in the cable pathways 2134 mm to 2438 mm (7 to 8 ft) above the floor and directly over the lineups. System cable racks running perpendicular (cross-aisle) to equipment lineups are typically 2438 mm to 2743 mm (8 to 9 ft) above the floor across the equipment area.
2–20
2438 mm (8’) 2743 mm (9’)3 048 mm (10’) Clear Ceiling 2134 mm (7’)NEBSTM Requirements: Physical ProtectionGR-63-CORE
Spatial Requirements
2.5.2.3 Via Cable Racks
Via cable racks running perpendicular (cross-aisle) to equipment lineups are
typically 2438 mm to 2743 mm (8 to 9 ft) above the floor across the equipment area. Via cable racks running parallel to equipment lineups shall be located within the cable pathways and are typically 2743 mm to 3048 mm (9 to 10 ft) above the floor, directly over the lineups. The lineup via pathways should have a maximum width of 305 mm (1 ft). The locations of lineup via cable racks shall be designated on system floor and cabling plans.
2.5.2.4 Lights
Lights may be supported from the CDS and thus by the frames below. Lights are located over maintenance aisles and below cross-aisle cable pathways. The vertical height of the fixture above the floor should not restrict installation of new frames in a lineup, and must permit adequate frame illumination as Section4.7 describes. Lights should be located within the lighting pathways, shown in Figure2-11, in an arrangement that allows access to overhead cable racks.
2.5.3 Cable Pathways Over Distributing Frame (DF) Areas
A cable pathways plan should be prepared for each DF area. This plan should allocate the space over DFs to system and via cable racks, lights, and installer access. System cabling interconnects different parts of the same DF and includes terminating via cable. The other via cabling passes over the frame. Figure2-11 shows a typical cable pathways plan for a DF area.
2.5.4 CDS Floor Load and Support
O2-44[37] The floor load from overhead CDSs (including lights) should not exceed
125 kg/m2 (25.6 lb/ft2). The system CDSs are allocated 100 kg/m2 (20.5 lb/ft2) and via CDSs are allocated 25 kg/m2 (5.1 lb/ft2). This weight allowance may be averaged over an area not exceeding 6.1-m × 6.1-m (20-ft × 20-ft) square and must include all cable, rack, lights, and associated support hardware.
2–21
NEBSTM Requirements: Physical ProtectionGR-63-CORE
Spatial Requirements
Figure2-4 Typical Equipment Frame Area (Vertical Section)
Lowest Structural
MemberAir DiffuserSuspended Lowest Structural
MemberCeilingAir DuctCable RackAir Plenum3 810 mm(12’ - 6\) 3 048 mm(10’) Lights Frame Lineup Raised Deck SupportWorkConventional Cooling System (CCS)Top of Floor Slabs
Modular Cooling System (MCS)2.2.2 Equipment Frame Dimensions
Figure2-5 shows the conventional nomenclature for overall dimensions of equipment frames.
These dimensions include any equipment that is part of the frame or routinely left attached to the frame, particularly any front or rear projections, such as knobs, paper guides, or cable.
3 048 mm(10’) 3 810 mm(12’ - 6\)2–7
Spatial Requirements
GR-63-COREIssue 3, March 2006
Figure2-5 Equipment Frame — Overall Dimensions
WidthHeightDepthO2-15[13] Frames with their system cable racks should not exceed 2743mm (9 ft) in
height above the floor.
A frame with its system cable racks exceeding a height of 2743 mm (9 ft) may be used with the requirements in this document. In offices with a clear ceiling height of 3810 mm (12 ft, 6 in), the above frame will reduce the vertical space allocated to via racks and the mechanical systems.
2–8
NEBSTM Requirements: Physical ProtectionGR-63-CORE
Spatial Requirements
2.2.2.1 Equipment Frame Dimensions - Open Style Racks
Many equipment areas use open style racks to support equipment chassis or shelves. These racks are very common in transport and common systems areas of network facilities. A number of common rack dimensions are used and standards such as EIA-310-D, Cabinets, Racks, Panels, and Associated Equipment, address the detail engineering of these products.1
O2-16[14] Open style equipment racks should have the following nominal overall
dimensions:
Height Nominal 2130 mm (7 ft)WidthNominal 560 mm (23 in) for 19-inch equipment
Nominal 660 mm (26 in) for 23-inch equipment Depth
Nominal 300 mm (12 in)
In CO applications, the wider width is the most common. Chassis suitable for mounting in a 560 mm rack can be supported by the wider rack via alternative mounting hardware or adapters. Chassis deeper than 300 mm (12 in) can be supported in open-style racks if base extenders are used as required by R2-5 [5].Base extenders are commercially available and are provided by rack suppliers to protect equipment that protrudes beyond the standard rack base.
O2-17[148]Open-style racks should not be used for products deeper than 600 mm (24 in)
even when base extenders are used.O2-18[149]For chassis depths > 450 mm (18 in), provisions to fasten the chassis to both
front and rear faces of the rack mounting flange are desirable.
2.2.2.2 Equipment Frame Dimensions - Other Rack Styles
Some newer equipment areas use other rack styles, such as four-post racks or cabinets, to support equipment chassis or shelves. These racks may be open in construction (similar to the traditional open style racks) or may be enclosed by doors, side panels, or tops. Regardless of the construction details, these frameworks are usually provided in depths greater than 300 mm (12 in) and are able to support deeper chassis than traditional open style racks. A number of sizes are available, but the following are most desirable for efficient allocation of space. The engineering and performance of these products are detailed in ANSI T1.336-2003, Engineering Requirements for a Universal Telecom Framework.
1.EIA-310-D specifies a usable opening of 19-inch racks to be 17.750 inches, while rack vendors fabricate seismic-compliant racks with an opening of 17.500 inches.
2–9
Spatial Requirements
GR-63-COREIssue 3, March 2006
O2-19[150]Equipment racks for newer equipment areas or to support deeper chassis
should have the following nominal overall dimensions:
Height Nominal 2130 mm (7 ft)WidthDepth
Nominal 600 mm (24 in), or
Nominal 750 mm (30 in) Nominal 600 mm (24 in), orNominal 750 mm (30 in), orNominal 900 mm (36 in)
2.2.2.3 Equipment Frame Dimensions - Special Cases
Frames may exceed the objective dimensions for width and depth when placed in a special lineup where the minimum maintenance and wiring aisles can be maintained and the interface with the cable rack can be engineered.
Switching systems with lineups of equipment that include system cable racks may deviate from the objective dimensions. Such systems must still meet the requirements for lineup conformity in Section2.1, “General Requirements.” Figure2-6 is an example of a floor plan of a switching system for illustrative purposes.
2–10
NEBSTM Requirements: Physical ProtectionGR-63-CORE
Spatial Requirements
Figure2-6 Typical Equipment Area Using Frames 1829 mm (6 ft, 0 in) High,
762mm (2 ft, 6 in) Wide, and 610 mm (2 ft, 0 in) Deep
610 mm (2’) 762 mm (2’ 6\ 762 mm (2’ 6\Wiring Aisle610 mm Min. (2’)610 mm (2’) Overall Footprint Including Projection 1 829 mm (6’)1 067 mm (3’ 6\Maintenance AisleFrame Outline6.1 m (20’)762 mm (2’ 6\Wiring Aisle1 067 mm (3’ 6\Maintenance Aisle864 mm Min. (2’ 10\ 6.1 m (20’)Building Bay Plan
2.2.2.4 Equipment Frame Cable Management Provisions
R2-20[151]All framework shall provide access to permit cabling from top or bottom.O2-21[152]All framework should be manufactured to allow orderly placement of larger
cables, i.e., power conductors, such that these do not interfere with access to equipment mounted in the framework, each other, or other cables routed into the framework.
2.2.2.5 Equipment Frame Interface with Cable Rack
R2-22[15] Equipment frames shall be capable of supporting and providing a fastening
arrangement for all system Cable Distribution Systems (CDSs). The design of the interface between the frame and CDS shall permit the insertion or removal of a frame from an equipment lineup. To permit this insertion or removal, a minimum clearance of 10 mm (0.39 in), except for spacers, shall normally be provided between the top of the frames and the bottom of the CDS.
2–11
Spatial Requirements
GR-63-COREIssue 3, March 2006
O2-23[16] Framework top cross-member should provide the following fastenings: a
minimum of two 13-mm (0.51-in) diameter holes (with room for a nut) or two M10 (or 3/8 - 16) tap-through holes (with at least four full threads). The holes shall be located on the longitudinal center line and 121 mm (4.75 in) to either side of the front-to-back center line of the framework top, as Figure2-7 shows.
When the fastenings in the top of the framework do not align with the holes in the system lineup rack, an adapter plate that mounts on the top of the framework may be used as Figure2-7 shows.
2.2.3 Equipment Frame Lineup Conformity
R2-24[17] End guards for equipment frames shall be as wide as the equipment frames are
deep and extend the full height of the frame. The minimum aisle spacings must be maintained when the end guards are added to an equipment lineup.
2.2.4 Equipment Frame Floor Loading
O2-25[18] An individual frame should be limited to a floor load of
560kg/m2 (114.7 lb/ft2). The floor load for an equipment frame is calculated by dividing the frame weight by the area of a rectangle bounded by the extended frame sides and the center line of the standard front (762 mm or {2 ft, 6 in}) and rear (610mm or {2 ft}) aisles.R2-26[19] An equipment frame shall be able to support all overhead CDSs and lights
located up to 3048 mm (10 ft) above the floor and having a maximum weight of 125 kg/m2 (25.6 lb/ft2). In partially equipped lineups, CDSs and lights may be partially supported by floor-mounted stanchions. Over unequipped areas, via CDSs (defined in Section2.5) may be supported by stanchions or from the ceiling.
In addition to the 560-kg/m2 (114.7-lb/ft2) equipment frame load and the 125-kg/m2 (25.6-lb/ft2) CDS and lighting fixture load, there is a 50-kg/m2 (10.2-lb/ft2) transient load. The sum of these individual loads equals the floor-loading limit of 735 kg/m2 (150.6 lb/ft2).
2–12
NEBSTM Requirements: Physical ProtectionGR-63-CORE
Spatial Requirements
Figure2-7 Typical Adapter Plate, Spacer, and Hole Locations in the Top of the
Framework
2–13
Spatial Requirements
GR-63-COREIssue 3, March 2006
2.2.5 AC Convenience Outlets Within Equipment Frames
R2-27[20] The base of each frame, behind the front and rear guardrails, shall have space
for ac power distribution for convenience outlets. The sides of the frame base must be sufficiently open or have holes that permit distribution wire to run through the frames. The front and rear of the frame base and/or guardrail shall provide the means and location for convenience outlets. When design control for a system includes the end guards at both ends of a lineup, the convenience outlets may be located in the end guards instead of in the base of each individual frame.R2-28[21] Alternating current power distribution for connecting outlets or lighting
fixtures that may be part of the frame assembly shall be designed and constructed to comply with the National Electrical Code (NEC), except where those
requirements are superseded by applicable local electrical and building codes.
2.3 Distributing and Interconnecting Frames
This section presents spatial and floor loading requirements that are unique to distributing frames and interconnecting frames.
2.3.1 Distributing Frames (DFs)
Distributing Frames serve as a common termination point for the interconnection of metallic OSP cabling, and CO equipment interfaces. DFs provide protection, cross-connection, and test access to equipment and cabling. DFs are not installed in lineups with other equipment frames. Samples of type of DFs include the following:
?Main Distributing Frame (MDF) ?Protector Frame (PF).
Figure2-8 shows a typical network distributing frame area. Objectives and
requirements for the frames (which include associated overhead dedicated cabling and cable racks) are described below.
O2-29[22] Frames should have a maximum height of 2743 mm (9 ft) including associated
system cabling, which includes all terminating cabling and racks. The space from 2743 mm to 3048 mm (9 to 10 ft) should be shared between the system and non-terminating via cabling. In long DF lineups, system cabling may be more than 2743 mm (9 ft), but must be less than 3505 mm (11 ft, 6 in) above the floor.
Nonconforming frames may be used with the requirements in this document; however, special consideration is necessary to ensure the frame cabling will not interfere with via cabling, air ducts, or other building systems.
R2-30[23] Frames shall have a maximum floor load of 675 kg/m2 (138.3 lb/ft2). This
uniform load is the total weight of all distributing frame equipment in the area, including cabling and racks, divided by the associated floor area, including aisles. When such areas exceed 37.2 m2 (400 ft2), any 6.1-m × 6.1-m portion (20-ft × 20-ft),
2–14
NEBSTM Requirements: Physical ProtectionGR-63-CORE
Spatial Requirements
regardless of its location relative to the columns, should not exceed the floor-load requirement.
O2-31[24] Frames should be capable of supporting all overhead cable distribution
systems and lights. In partially equipped lineups, cabling and lights may be supported by floor-mounted stanchions.
Figure2-8 Typical Network Distribution Frame Area
3810 mm (12’ 6\
3353 mm (11’) See Note
3048 mm (10’) Via Cable
Protection Frame
2743 mm (9’) Max (Including Cable and Clearance)
Main Distribution Frame
Note: The space between the 3048 mm (10’) and 3353 mm (11’) levels is normally reserved for air conditioning ducts, but over the main frame this space may be required for cable pileups.
2.3.2 Interconnecting Frames (IFs)
Interconnecting Frames provide for cross-connection and test access of CO equipment and cabling, as well as fiber optic cabling that may originate from the OSP. (OSP metallic cabling does not terminate on the IF.) IFs may be installed in lineups with equipment, or in separate lineups parallel or perpendicular to equipment frame lineups. Examples of IFs include the following:
?Intermediate Distributing Frame (IDF)?Circuit Concentration Bay (CCB)?Group Distributing Frame (GDF)?Digital System Cross-connect (DSX)
?Quick Connect and Cross-connect (QCX)?Trunk Distributing Frame (TDF)
2–15
Spatial Requirements
GR-63-COREIssue 3, March 2006
?Fiber Distributing Frame (FDF).
IFs are subject to all equipment frame criteria of Section2.2, “Equipment Frames.”
2.4 DC Power Plant Equipment
This section presents spatial and floor loading requirements that are unique to dc power plant equipment.
2.4.1 Centralized DC Power Plant Equipment
Centralized DC Power Plant Equipment — encompasses dc power plant equipment that is located in a separate “power room” or designated “power plant equipment area.” Such centralized DC power plants are typically separate from the equipment frame areas. A single power plant may serve one or more load equipment systems.
R2-32[25] The height of centralized dc power plant equipment, including all
superstructure and overhead facilities such as cable, cable racks, and bus bars, shall not exceed 3048 mm (10 ft). This vertical space allocation also includes any vertical clearance (headroom) necessary for installation, operation, and maintenance. Figure2-9 shows a typical centralized dc power plant equipment area.
Figure2-9 Typical Network DC Centralized Power Plant Equipment Area
Air DuctBus Bar or Cabling 3810 mm (12’ 6\PowerCabinetBatteries 3048 mm (10’) Max. (Including Cable and Clearance) 2–16
