RF
RFP 5343 - EXHIBIT 2
Specifications, Guidelines, & Practices Communications (Fiber, Radio Frequency) Shelter Specifications Part 1.
GENERAL 1.1. This Request for Proposal (RFP) and specifications are for a shelter to be supplied to Denton Municipal Electric Communications (DMEC) department. The shelter shall be a prefabricated concrete communications type. The building to be provided by the manufacturer will include all necessary openings as specified by the DMEC department in conformance with manufacturer’s structural requirements. 1.2. The specifications contained herein encompass the labor, equipment, and materials for a prefabricated concrete communications shelter. 1.3. The shelter shall be vandal resistant and constructed of steel reinforced concrete. 1.4. The shelter structure shall provide a 2‐hour fire rating as defined in the Uniform Building Code. 1.5. The shelter shall be designed for the explicit use of housing electronic equipment within a controlled atmosphere required for the proper conditions for transmitting and receiving equipment. 1.6. The shelter shall incorporate non‐porous wall and roof sections, to preclude capillary action, and shall be so designed, and constructed to provide a minimum useful life period of 20 years, with need for major maintenance actions. Manufacture shall provide shelter maintenance and warranty information. 1.7. Shelter manufacturer shall supply and install complete AC wiring systems as required by this specification and in compliance to applicable codes. Electrical systems shall be designed based on preliminary floor plan provided by DMEC. 1.8. Manufacturer shall supply and install complete air conditioning and heating systems as required complying with the environmental conditions of these specifications. 1.9. Manufacturer shall be responsible for the site preparation, transportation of the shelter to its respective site, and installation. 1.10.
Manufacturer shall design an I‐beam skid assembly, if required for transportation to the site, based on the requirements of this specification and install the shelter on the assembly. Fabricator will submit I‐beam assembly drawings within 10 days after receipt of order. 1.11.
All shelters shall meet the following specifications and standards: 1.11.1. Uniform Building Code 1.11.2. BOCA National Building Code 1.11.3. Standard Building Code 1.11.4. Local Basic Building Code 1.11.5. ANSI‐A.58.1 1.11.6. National Electric Code latest addition 1.11.7. IEC – Illuminating Engineering Society In the event that two specifications conflict, the more stringent shall apply. RFP 5343
Exhibit 2
Specifications, Guidelines & Practices Communications (RF & Fiber) Shelter Specifications 1.12.
The order of precedence to be used for this RFP provided by City of Denton Purchasing Department, specific program requirements, and this specification. Part 2.
SPECIFIC CONDITIONS 2.1. The shelter(s) shall be designed to meet the following conditions. 2.1.1. Seismic Zone 4 2.1.2. Ambient temperature of 70°C (158°F) to ‐55°C (‐67°F). 2.1.3. Ambient humidity from 0‐100 percent 2.1.4. Winds 145 mph (235 Km/Hr) while on specified foundation Part 3.
SHELTER SPECIFICATIONS 3.1. The manufacturer shall provide a shelter 20 feet wide (exterior) X 9 feet high (exterior) X 9 feet wide (exterior). The width value does not include roof overhang. A typical floor plan is shown in APPENDIX C. A program specific drawing will be provided when the order is placed. 3.2. Structural Loading – The shelter shall meet the following loading requirements. 3.2.1. 200 pounds per square foot distributed floor loading while lifting or on foundation. 3.2.2. 3000 pounds concentrated floor load over 4 square feet. 3.2.3. 90 pounds per square foot roof live loading – 7 day duration. 3.2.4. 1000 pounds concentrated roof load over 3 feet square area. 3.3. Thermal performance – Overall u factor ൑ .08 Btu/hr/degrees F 3.4. Operating Environment – The shelter shall be sealed to resist dust infiltration and be watertight. 3.5. Shelter Construction – The shelter shall be precast, preassembled steel reinforced solid concrete. Panel to panel connections to be welded. Manufacturer of the precast concrete element shall occur in a suitable environment (enclosed building preferred). Manufacturer must have a minimum of one ACI Certified Level 1 Concrete Technician supervising the placing of the concrete forms. 3.6. Floor Section – Floor section shall be an 8‐inch waffled structural precast steel reinforced concrete section. Ribs shall be 2’‐0” O.C. transverse and 4’‐0” O.C. longitudinal. All surfaces shall be smooth. The interior surface shall be covered with 1/8 inch light colored industrial vinyl floor covering, bonded with waterproof contact adhesive. The floor shall be supplied with provisions for customer anchoring of equipment. 3.7. Roof Section – The roof section shall be a minimum of steel reinforced 4 inch solid concrete with 1/8 inch per foot drainage slope. Ceiling insulation and finish to be foam board insulation with 3/8 inch vinyl coated board. Plastic joint or corner trim shall be installed at all panel joints. The roof shall provide at least a 2 inch overhang on all sides. The roof will be a hip type sloping two (2) directions. It shall be a cap and fit over the walls, leaving no exposed roof to wall joint. RFP 5343
Exhibit 2
Specifications, Guidelines & Practices Communications (RF & Fiber) Shelter Specifications 3.8. Sealing – All joints shall be sealed with compressible, resilient sealant. These shall be no exposed roof to wall or wall to floor exterior joint sealants. Wall to wall, wall to roof, and wall to floor seals shall be internal. 3.9. Exterior Walls: 3.9.1.Surface of walls to be sealed with two coats of Thoroglaze H Sealer and a top coat of Thorosystem’s Thorosheen Sealer or equivalent. 3.10.
Material Specification – The material specifications shall be as follows: 3.10.1. Concrete Compressive strength shall be 4000 PSI at 28 days. Mix design of 114‐118 lb/cu. Ft. structural lightweight concrete expanded shale or expanded clay aggregate is preferred. Mix shall be homogenous. Seeding of aggregate for exposed aggregate finish is not allowed. Cement used in concrete shall be standard Portland cement conforming to the requirement of the “Standard Specifications for Portland Cement”, ASTM Designation C150. 3.10.2. Concrete aggregates shall conform to one of the following specifications: 3.10.2.1. “Specifications for Concrete Aggregates”, ASTM Designation: C33. 3.10.2.2. “Specifications for Lightweight Aggregates for Structural Concrete”. ASTM Designation: C30. 3.10.3. Other Materials 3.10.3.1. Water shall be free from injurious quantities of oil, alkali, vegetable matter and salt. Non‐potable water shall not be used in mixing concrete. Reinforcement bars shall be deformed steel bars conforming to the requirements of the “Specifications for Deformed and Plain Billet‐Steel Bars for Concrete Reinforcement”, ASTM Designation: A615. 3.10.3.2. Welded smooth wire fabric shall be steel wire fabric conforming to the requirements of the “Specifications for Welded Steel Wire Fabric for Concrete Reinforcement”, ASTM Designation: A185. 3.10.4. The plywood panels shall be in accordance with stressed‐skin panel design of the Timber Design and Construction Handbook. 3.11.
Door – The door frame shall be 16 gauge galvanized steel, primed, painted, and fastened to the wall panel. The door shall be 3 foot X 7 foot X 1‐3/4 inch 18 gauge galvanized steel, insulated, primed, painted, and installed flush with the door check, door stop, weather‐
stripping, mortise lockset with deadbolt and stainless tamperproof steel ball bearing hinges. The shelter door shall have an internal lock mechanism to allow rapid exit from the building (no key exit). The door shall be equipped with a device to lock the door in the open position in order to prevent the door from being damaged by gusting winds. An illegal entry switch, with form ‘C’ contacts rated .1q amps at 28 Vdc shall be provided. 3.12.
Cable Entry Panel – Manufacturer shall provide and install a 4 (horizontal) X 3 (vertical) port/waveguide entry panel with 4 inch sleeves and protective blank covers as manufactured by PolyPhaser (PEEP), Microflect, or a DMEC approved equivalent. RFP 5343
Exhibit 2
Specifications, Guidelines & Practices Communications (RF & Fiber) Shelter Specifications 3.13.
Cable Ladder – Manufacturer shall provide and install 12 inch wide steel cable ladder/tray for cable distribution and seismic bracing of the communication equipment. The cable ladder shall be Uni‐Strut, Rohn, B‐Line, VFP, Inc., Newton, or a DMEC approved equivalent. The actual quantity will be determined by the size of the shelter and requirements. Location of the cable tray/ladder is defined in APPENDIX C of this document. 3.14.
Handling – Shelter shall have cast‐in permanent lifting devices so that additional parts of bolt‐on devices are not required for lifting the shelter. Part 4.
ENVIRONMENTAL CONDITIONS 4.1. The shelter shall be designed and equipment with an environmental control system consisting of air conditioning and heating capable of maintaining an inside temperature under operating conditions, plus sensible and latent heat gains from personnel, at 24°C (75°F) (±) 3°C (5°F). The internal temperature shall not rise above 30°C (84°F) with an outside ambient temperature of 45°C (110°F) (temperatures are to be maintained while the equipment is operating at 75% duty cycle) and shall not fall below 18°C (65°F) with an outside ambient temperature of ‐35°C (‐30°F) while equipment is OFF. 4.2. Air conditioning units shall be wall‐mounted type as manufactured by Bard, Marvair, Carrier, or a DMEC approve equivalent. The units shall be equipped with as a minimum low ambient and compressor anti cycle controls, and integral resistance heat strip (s) and permanent expanded metal dust filter (s). 4.3. The air conditioning unit (s) shall be controlled via a separate remote mounted thermostat. If more than one unit is required, a redundant lead lag controller which allows for approximate equal operating time on each air conditioner unit is to be provided. The system shall provide switching to prevent both units from activating at the same time so as to prevent power surge. 4.4. The air conditioned air shall be directed toward the center aisle as shown in DMEC drawing APPENDIX C to support DMEC station equipment. 4.5. All temperature control equipment shall be installed in strict compliance with manufactures instructions and guidelines. 4.6. Heating and cooling calculations based on manufacturer installed equipment and customer installed heat loads shall also be required. 4.7. The manufacturer shall supply contacts or switches necessary to report high and low temperature alarms using the DMEC SCADA and communication system. Part 5.
ELECTRICAL AND LIGHTING 5.1. The shelter manufacturer shall supply and install a complete working electrical system including the following: 5.1.1.Main power distribution provision for service entrance (200 Amp) 5.1.2. Interior lighting to include six (6) four feet, two tube fluorescent lighting (T8). RFP 5343
Exhibit 2
Specifications, Guidelines & Practices Communications (RF & Fiber) Shelter Specifications 5.1.3.Exterior lighting to include one (1) exterior door light adjacent to the doorway. 5.1.4.Receptacles to include four (6) 110V duplex receptacles and one (1) exterior GFI receptacle. Placement of the duplex receptacles will be per locations shown in APPENDIX C of this document. 5.1.5.One (1) 18 kVA Uninterruptible Power Supply System. Batteries shall be sealed. 5.1.6.The manufacturer shall supply contacts to provide an alarm if the shelter experiences a power lost. The contact must be able to utilize the DMEC SCADA and communication network. 5.1.7.The minimum fire protection required for the shelter is a smoke alarm. The alarm must provide the necessary contact to transmit a signal utilizing the DMEC’s SCADA and communication network. In addition, a Class ABC fire extinguisher is required as well as an extinguisher that utilizes inert gas or other DMEC approved clean agent suppression. Automatic fire suppression system may also be required. Part 6.
GROUNDING SYSTEM 6.1. Grounding of the communication shelter must be consistent with the DMEC grounding requirements for communication sites and shelters as defined in APPENDIX B of this document. 6.2. The manufacturer shall install a “halo” ground system consisting of a #2 AWG stranded green insulated copper halo located approximately 6 inches below the ceiling (see Figure 2 or Appendix A) with vertical #2 AWG bare/tinned solid copper drops at each corner of the building (See Figure 1 e.g. “PVC” Nipple). At these drop locations a length of bare/tinned solid copper wire capable of extending through and beyond the PVC nipple at least 10 feet shall be coiled and secure to the wall. The customer will use these to connect to the on‐site grounding system. 6.3. The shelter floor will be supplied with penetrations as per Figure 1 to allow the customer to exit at each corner wall location with the #2 AWG halo ground. Silicone sealer or equivalent shall be supplied for customers use to seal these penetrations after grounding connections have been made. An internal shelter “ground‐bar” shall be installed as described in Figure 3. 6.4. Cable, trays, ladders, and metal doors shall be bonded to the internal ground ring as illustrated in Figure 4. 6.5. Conduits and conduit couplings shall be bonded to the ground system in a manner consistent with attached Figure 5. 6.6. All coax cable and/or waveguide entry grounds will terminate at the “ground window” or a PolyPhaser Earth Entry Panel (PEEP) ground bar installed in an area near to, and/or below the cable multi‐port entry panel. A description and example of the ground bar is illustrated in Figure 3. 6.7. Grounding of electrical power and surge suppression equipment shall be done in strict compliance to the latest edition of the National Electric Code and manufacturer’s data. RFP 5343
Exhibit 2
Specifications, Guidelines & Practices Communications (RF & Fiber) Shelter Specifications Part 7.
QUALITY ASSURANCE 7.1. The shelter manufacturer shall have a quality assurance program to ensure that its buildings meet the industry standards. Through this program incoming and in process inspections, components, assemblies, and finished shelter shall be checked for compliance with customer specifications, engineering specifications and drawings. An inspection log shall also be maintained with inspection disposition recorded by the Quality Assurance inspector. These records shall be available for inspection upon request. The major inspection categories are I‐
beam skid, framing, assembly, concrete, steel assembly, electrical, finish, grounding and preparation for shipping. 7.2. All equipment and hardware shall be installed in the shelter using best commercial practices. All wall and flour mounted equipment shall present a neat and symmetrical appearance and shall be installed to withstand shock and vibration due to shipping. 7.2.1.Shelter and accessories, when finished, shall be complete in every respect and ready for the use intended. Part 8.
DOCUMENTATION 8.1. Manufacturer shall submit, after receipt of order, preliminary drawing and documentation consisting as a minimum the following. 8.1.1. Shelter layout and structural dimensions. Included shall be drawings and applicable data on equipment included as part of the shelter. 8.1.2. A legend which identifies major components and systems. 8.2. DMEC will after receipt of preliminary drawings and design information review and approve and return one signed copy with one of the following: 8.2.1.APPROVED ‐ Prints so marked will authorize the manufacturer to proceed with fabrication of the shelter. 8.2.2.APPROVED AS NOTED – Prints so marked will authorize the manufacturer to proceed with the fabrication of the shelter only after the necessary corrections to drawings have been completed. 8.2.3.NOT APPROVED – The manufacturer shall make the corrections on the drawings and will be required to resubmit for DMEC approval. The time require for such re‐submittals of drawings does not entitle the manufacturer to any extension of time. However, DMEC may grant an extension upon request if time permits. 8.3. The manufacturer shall also provide upon completion the following: 8.3.1. One set of “as‐built” drawings and parts list shall be completed and provided with a shelter on shipment. An Operation and Maintenance Manual shall be provided with each shelter system. Included in this manual, as a minimum, shall be the manufacturer’s data and warranty information on all available electrical systems and supplied equipment. Shelter start‐up information and maintenance procedures shall also be provided. RFP 5343
Exhibit 2
Specifications, Guidelines & Practices Communications (RF & Fiber) Shelter Specifications 8.3.2.Manufacturer shall provide quality assurance acceptance documentation on completion of the shelter. Part 9.
CERTIFICATION 9.1. It is the manufacturer’s responsibility to supply DMEC with any necessary approval or state certification that may be required. 9.2. Professional Engineer (PE) sealed drawings up to six (6) sets may be requested. Part 10. BIDDERS INSTRUCTIONS 10.1.
The shelter bidder will submit the following information with his proposal: 10.1.1. Price 10.1.2. Delivery schedule 10.1.3. Shipping cost (separately) 10.1.4. Verification that the shelter will be approved in the State where required. 10.2.
The manufacturer shall guarantee that all materials and workmanship shall be free from defect for a period of two (2) years after delivery. 10.3.
The manufacturer shall guarantee the shelter construction for a period of five (5) years after completion and installation. 10.4.
The manufacturer will address each paragraph of this specification and explain their compliance or exceptions. 10.5.
Technical questions regarding this specification should be sent to: Denton Municipal Electric Division Engineering Manager – Distribution 1685 Spencer Road Denton, Texas 76205 Attention: Jerry Fielder Telephone: (940 321‐7889 Email: jerry.fielder@cityofdenton.com RFP 5343
Exhibit 2
APPENDIX A – FIGURES Figure 1 ‐ Acceptable methods to connect inside "Halo" ring to the external ground ring Figure 2 ‐ "Halo" connections ‐ Inside building RFP 5343
Exhibit 2
Figure 3 ‐ Ground Bar Installations Figure 4 ‐ Cable trays and door bonding RFP 5343
Exhibit 2
Figure 5 ‐ Conduit Grounding Grounding and Application Notes Conduit Size ½ inch to ¾ inch ½ inch to 1 inch ½ inch to 1 inch ½ inch to 1 inch ½ inch to 2 inch 1 ¼ inch to 2 inch 1 ¼ inch to 2 inch 2 ½ inch to 3 ½ inch 2 ½ inch to 3 ½ inch 4 inch to 5 inch Wire Size #4 – 6 #14 – 2 #2 – 6 #4 – 4/0 #6 – 4/0 #2 – 6 #4 – 4/0 #2 – 6 #4 – 4/0 #2 – 6 Ground Clamp # T&B 3846 T&B 3849 T&B #2 T&B 3902 T&B 3970 T&B #3 T&B 3903 T&B #4 T&B 3904 T&B #5 Table 1 a)
b)
c)
d)
e)
Apply “no‐ox” grease to all ground bar of halo ground connections; wipe clean any excess. Bond exterior door frame to halo ring. Make all connections to ground bar with two‐hole lugs. Coil 8 feet of #2 green for future connection to exterior ground ring. Use only brass grounding hardware except where noted. See Table 1 for approved part numbers. f) Jump all breaks in conduit, junction boxes, connectors, etc., with #6 green. g) Ground all metal boxes larger than 4X4 and metal framework to the halo ground with #6 green. h) Select grounding clamps for conduit in accordance with Table 1. RFP 5343
Exhibit 2
APPENDIX B – GROUNDING Part 1 – OBJECTIVE The fundamental objective is to provide a standard for site equipment grounding with the recommended methods that are essential to protect personnel, minimize components failure, and optimize performance by reducing electric noise. Transient voltages introduced into a system often exceed the operating parameters of electronic component and have destructive results. The fragile nature of semiconductor makes them even more susceptible to these externally induced transient voltages. 1.1 Grounding Theory In theory, a ground rod 1 inch in diameter driven into homogeneous 1000 ohm per meter (ohm/meter) solid for one meter would present only 765 ohms. Driving it another meter into the soil (two meters) would yield 437 ohms. Extending the depth to three meter would yield about 309 ohms. By using three ground rods that are each one meter long, and driven into the same soil area one meter deep and one meter apart we could achieve a ground resistance of 230 ohms. We quickly realize that we can get faster ohms reduction in ground resistance by installing multiple ground rods. If we also bury the interconnection wire below the soil surface we are able to lower the ground resistance below 200 ohms. With these conditions as a point of reference, the DMEC site installation should exhibit better than (below) 5 ohms resistance between any connected point on the ground bus and earth ground. The exception to this requirement is noted at section 2.1.4 ANTENNA STRUCTURES ON TALL BUILDINGS. When making these measurements, an instrument similar to the AEMC Model 3700HD will be used to make these measurements. The measurements will be made using the instructions provided with the AEMC 3700HD Ground Test Instrument. 1.2 Scope These specifications and requirement are prepared for both safety and damage prevention measures. The grounding, bonding, and shielding procedure are implemented to prevent damage to equipment, reduce Radio Frequency spectrum pollution, and as a safety measure for maintenance and operations personnel. The prime source of danger and damage is from lightning current which are other conducted to the equipment by way of the coax transmission line. RFP 5343
Exhibit 2
One of the better means to reduce the chance for damage from this source is to provide a low impedance path to ground for these current without having the currents flow through the equipment. 1.3 General The following needs constitute a justification for grounding: The need to control fast‐rising electrical surges which produce high voltage difference between the ends of single conductors such as heavy copper wires and bars. The need to equalize surge potentials by controlled bonding of DMEC site ground elements. These elements include the following: a) Non Isolated Ground Zones (IGZ) equipment grounds b) Surge Produces c) Surge Absorbers (provides path to ground) d) IGZ Grounds The need to reduce voltage difference and control surge current by using single‐point grounding, which includes the following elements: a) A common or master ground bar configuration for establishing a common voltage reference phase (with respect to earth “true” ground) for the entire DMEC site and for dispersing lightning and power surge activity rapidly to earth via the halo and ring ground system. b) A ground window bar, or equivalent, to establish a local point of reference potential for grounding sensitive electronic equipment. This is terminated on the master ground window as the single point ground and voltage reference for all equipment at the DMEC installation. c) A single ground point in the isolated Ground Zone is at the master ground window. This again insures that potential equalization is true to any attached ground windows and equipment. d) The single point master ground bar will be cleaned to remove any oxidation to insure a low resistance connection. To establish sufficient metal to metal contact, an anti‐corrosion or antioxidant material is added at any connection point where grounding conductors are terminated. 1.4 Responsibility Throughout this document there will be references to ground rods and ground connections. In all cases mentioned there will be only one ground system allowed at each site, building, room, or communications shelter. ALL GROUNDS ARE TO BE TIED TOGETHER. There shall be no separately maintained ground rods or ground system associated with the communications shelter, site, building, or equipment room. RFP 5343
Exhibit 2
Adherence to these requirements becomes the performance standard with respect to Denton Municipal Electric’s Communications systems. Minimum Requirements The purpose of the specification is to establish, minimum requirements for a grounding system which will provide a measure of personnel and equipment protection. In the event that any item specified within this document conflicts with the National Electrical Code or local building‐grounding related codes, those codes take precedent. Protective measures to prevent equipment damage and personnel hazards against lightning will incorporate system grounding and bonding using good RF practices. While all conductors and connections have some associated resistance, the inductive reactance is normally much larger. All grounding and bonding conductors have low inductance interconnections to minimize the inductive voltage transients. As stated in the general overview of this document, all element of the system, and conductive elements in near proximity to the system are grounded and bonded together. This performs the function of maintaining any and all part of the radio site at the same level of ground integrity as related to true ground. 1.5 Process & Definition Coax and Transmission Line Grounding At DMEC repeater sites and antenna tower locations, our installers must attach three lightning protection grounding kits to each coaxial line used at the site. Each coax run will have a gas tube type, or equivalent, lightning arrestor installed onto the coax near the cable entrance to the communications shelter or room. These are believed to be the best lightning arrestors available today. These grounding kits will be terminated onto the master ground bar. All connections to the master ground bar window will be clean and free of any oxidation to insure a low resistance connection. Each of these arrestors is effective in limiting the amount of lightning energy that can be transferred to the equipment via the inner conductor of the coax or transmission line. Equipment Grounding Each equipment rack, equipment cabinet, or equipment shelf will be grounded to a site ground via the inner building halo ground. In the case of communications shelters, the equipment enclosure will be attached in the same manner to this system “halo” ground. 1.6 Ground Wire Composition RFP 5343
Exhibit 2
No grounds will be run inside metal conduit because metal conduit increases the surge impendence of the grounding cables. The ground which will make up the “halo” ground will be of number 2 AWG or large copper wire covered with a non‐conductive approved plastic covering. This covering is light green. Where the halo ground is attached to the exit ground wire, these wire(s) will be solid, tinned, bare copper, number 2 AWG or larger. A complete grounding system for the antenna, towers, and buildings are provided. These include internal and external grounding systems for equipment in the communications building, grounding or the antenna towers and guys, transmission line, telephone line and AC power line grounding and grounding of the communications facility. Ground Rods Where a DMEC ground system is installed, ground rods will be bare copper, 5/8 inch in diameter, and a minimum of 8 feet in length. As discussed in “General” (1.3) at the beginning of this document, multiple interconnected ground rods are normally provided. 1.7 Conductors Conductors that are employed below ground for the purpose of connection ground rods will use: a) Stranded copper wire, number 2 AWG or larger b) Solid copper strap, with minimum of 18 AWG and minimum width of two inches. Conductors used above ground for interconnecting ground rings, halo’s equipment (racks and cabinets), and other metal items will be: a) Solid or stranded copper wire number 6 AWG or larger. b) Solid copper strap, with minimum thickness of 16 AWG and a minimum width of one inch. Precautions against the use of connection where dissimilar metal might cause deterioration of grounding surfaces are observed. Below are lists of metals divided into groups. By avoiding the use of metals from one group attached to a metal of another group, we prevent ground contact surface deterioration. Group A Group B Group C Group D Magnesium Tin Stainless Steel Copper Aluminum Lead Nickel Silver Zinc Steel Iron Metal surface contact of meal in the same ground may be used with the following stipulations: Contact Surfaces Inside Outside (Weather Exposed) Within same group OK OK RFP 5343
Exhibit 2
Contact Surfaces Adjacent Groups Inside OK1 Outside (Weather Exposed) Weatherproof coating must be applied after direct metal‐to‐
metal contact.1 1.8 Connections All connections are made with minimum length conductors, with straight vertical (or horizontal) runs, if possible. Conductor bends, when required, will be greater than a 12‐inch radius. Connecting conductors will always transition in the direction of current flow or toward earth ground, and approach the main ground at an angle of roughly 45 degrees. Below Ground Connections made to ground rods, or to conductors below ground must be made using an exothermic (heat producing) process such as Cadweld or equivalent. This attachment procedure insures firm, mechanically rigid, and maintenance free connections. Connecting and interconnecting conductors are placed at the same depth as the top of the ground rods. Cadweld is a bonding process that provides a metallic bridge connection that exhibits virtually no resistance and its conductivity approximates that of the associated conductors. Above Ground Where possible, connections made above ground, in areas exposed to weather, the Cadweld or similar process will be employed. If environmental conditions prevent the use of Cadweld process, the use of an appropriate pressure‐type connection will be used. Where above ground pressure type connections are employed, stranded wire will be used. Connections made above ground will be made with appropriate passivation of the mating surface, or use special transition clamps such as PolyPhasor Model J‐1, J‐2, or equivalent. Connections to tower guy wires will use pressure connections. 1.9 Surge Suppression Devices Manufacturer Surge suppression device types referred to in this document are recommended and may be substituted as long as the substitution is of the same quality and performs the same function. Consideration must be given to voltage clamping level, response time, and energy rating for the intended application. The following practices are to be avoided: 1
No liquid should be allowed to come into contact with surface gaps of meal contact from adjacent groups. RFP 5343
Exhibit 2
a) Ground wire runs through metal conduit. If an occasion presents itself where the ground must be carried through a metal conduit, the ground wire must be bonded at each end of the conduit. The use of PVC conduit is preferred. b) Reliance on the third wire (green wire) on AC power lines for lightning ground. Part 2 – EXTERNAL GROUNDING SYSTEM External grounding rings installed by DMEC or approved contactors will individually encircle the antenna tower, the building, or equipment shelter. Ground rods for the tower and building are installed so that the top of the rod(s) is a minimum of 12 inches below the soil surface. The ground rods for tower ground will be installed so that the bottom end of the rod is deeper than the lowest part of the tower footing. Each ground ring listed above, such as the tower, building, fence, other object will be interconnected with a minimum of two (2) stranded copper wires number 2 AWG or larger. Where possible, connections to the ground rings will be made using the exothermic (Cadweld process or equivalent) weld. 2.1 Antenna Tower Grounds Where monopole masts are employed the ground system will consist of a minimum of three ground rods, connected together per the section on “Conductors: below Ground.” The mast connection to the ground system will be make with stranded wire number 2 AWG or larger. Connections to the mast will be in accordance with the manufacturer’s instructions. The connections will be short and direct with no sharp bends. Wooden Antenna Poles At installations where wooden antenna poles might be employed, the ground system will consist of a minimum of two ground rods connected together and installed per the paragraph “Conductors: Below Ground.” Atop the pole, ground connections to the antenna or antenna mast are made per manufacturer recommendations. A number 2 AWG or larger stranded copper ground wire will be run down the pole, and away from all other conductors to avoid possible flashover. Self Supporting Lattice Towers The self supporting lattice tower grounding system consists of a ground rod at each tower leg. If necessary, additional ground rods may be used to decrease ground resistance where needed, or be used to reduce the distance between rods. Ground rods must be connected together per paragraph RFP 5343
Exhibit 2
“Conductors: Below Ground”. Each tower leg is connected to the grounding system with number 2 AWG stranded wire or larger. Connections to the tower leg will be short and direct with no sharp bends. In addition to tower leg grounding, a ground rod must be installed at each guy anchor point approximately one foot from the anchor footing. The top of the ground rod will be a minimum of 12 inches below soil surface. The bottom of the ground rod will extend below the lowest point of the anchor footing. Number 2 AWG stranded copper wire is used to connect each of the guy wires to the ground rod at the guy anchor. Each ground rod is to be tied back to the tower “ground ring” below using number 2 stranded copper wire. Guyed Lattice Towers The guyed lattice tower grounding system consists of three ground rods at the tower base. These ground rods must be connected together per paragraph “Conductors: Below Ground”. The ground conductors used to connect the grounding system will be number 2 AWG stranded wire or larger. Connections to the tower will be short and direct with no sharp bends. In addition to the tower leg grounding, a ground rod must be installed at each guy anchor point approximately one foot from the anchor footing. The top of the ground rod will be a minimum of 12 inches below soil surface. The bottom of the ground rod will extend below the lowest point of the anchor footing. Number 2 AWG stranded copper wire is used to connect each of the guy wires to the ground at the guy anchor. Each ground rod is to be tied back to the tower “ground ring” below ground; using number 2 AWG stranded copper wire. Antenna Support Structures On Buildings Radio antenna installation stop building will have the tower, down conductor, transmission line shields, and other conducting objects within 6 feet of the tower or antenna base securely bonded together per paragraph “Conductors: Above Ground” (1.7) and “Connections: Above Ground (1.8.‐1.8.2.).” Atop steel‐frame structures, where possible, the common bond point may be bonded to building steel with number 2 AWG or larger copper wire. If available, the tower may also be bonded at roof level to a large metal, earth grounded, and cold water pipe. Atop reinforced concrete building, the common bond point should be connected via number 2 AWG or larger, stranded copper down conductors. These may be bonded to the earth grounded cold water main in the basement of the building or bonded to the building ground rod system. If available, the tower should also be bonded at roof level to a large metal, earth grounded, and cold water pipe. Guy wires associated with towers atop buildings should be grounded at their anchor points to a common bond point in the same manner as for grounding terrestrial towers. A dissimilar metal interconnect device will be used between the guy wire and the ground wire. Where the ground wire from multiple guys are daisy‐chained, the will be at least a three inch “play” loop between guy‐to‐guy ground connections. RFP 5343
Exhibit 2
In the above case where tall building ground are in use, the ground resistance should be maintained below (better than) ten (10) ohms between any equipment connected ground bus and earth ground. When making these measurements, an instrument similar to the AEMC Model 3700HD will be used to make these measurements. The measurements will be made using the instructions provided with the AEMC 3700HD Ground Test Instrument. 2.2 Equipment Buildings External “halo” ground is the grounding system around the exterior of the communications shelter or building. This ground system consists of a ground rod at each corner of the building. As necessary, additional ground rods will be added such that the distance between rods is less than 10 feet. A ground rod is installed directly below the coax transmission line entrance to the building. Ground rods are spaced approximately 2 feet out from the perimeter of the building. 2.3 Bulkhead Panel A weatherproof metal bulkhead panel should be installed on the building equipment wall. The panel will be comparable to the Andre Type 204673 or equivalent. The size should be determined by the number and size of transmission line interconnecting through it. The appropriate Andrew cable boots, or equivalent, are used for the weatherproof connections. The external panel must include a ground bar for transmission line shield ground connections and connections to the external ground system. The ground bar should be fabricated to avoid dissimilar metal connections as stated in this document (see paragraph “Conductors: Above Ground”). The bar must be connected to the building external ground system by number 2 AWG (2 conductors may be employed to form a low inductance path to the system ground). An internal sub panel, bolted directly to the bulkhead panel with multiple bolts may be used to mount the transmission surge suppressor specified in paragraph “Coaxial Suppressor”. The sub panel must be securely fastened with a low resistance, low inductance path to the bulkhead panel (stranded number 2 AWG or larger). 2.4 Fences Where possible to do so, metal fences within 6 feet of any ground ring or any grounded object will be grounded at twenty foot intervals along its length or at a minimum of each corner post and at each gate metal support post. This is to provide additional shock hazard protection from lightning. A minimum 8‐foot 5/8 inch copper or copper‐clad ground rod shall be installed into the ground within one foot of the fence, near a fixed gate hinge post where appropriate. The top of the ground rod will be a minimum of 12 inches below the ground surface, at the same level as the external ground ring to RFP 5343
Exhibit 2
which it will be connected. Additional ground rods may be installed for each 20 feet of fence at equal spacing. Each ground rod will be connected underground by the most direct path to the nearest tower or building ground ring using a stranded copper wire, number 2 AWG or larger. Above ground connection will be made by use of a pressure clamp near the bottom of the metal post. If below ground connections are used, it will be made by exothermic weld (Cadweld). Tinned copper ground strap (braid) is use to connect metal fence gate(s) to the main post. Pressure clamps are employed with these connections. Nearby Metal Objects The following components are connected to the external grounding system using a number 2 AWG, or larger, stranded copper wire. The transmission line entry window into the building, as this is the entry point into the equipment area. All transmission lines are grounded to this window, and extra care is employed to ensure a very low inductance path to ground. a) Ice shield and exterior cable tray between tower and building. b) Emergency generator and any generator supporting platform or base. c) Fuel tank(s) above or below ground. d) Other large metal or conductive objects within 6 feet of the communications shelter, tower, or the system ground. e) To other ground systems provided by telephone company, or the electric utility provider(s). Local electrical codes shall be observed when making this attachment. 2.5 Transmission Lines The following applies to the antenna and transmission lines outside the communications shelter or building where entry is made into the equipment shelter. These requirements do not apply to antenna and transmission lines that are contained entirely within the equipment of communications shelter. Shield Grounds The outer conductor of coaxial transmission cable must be grounded with an appropriate coaxial cable grounding kit. These grounding kits are installed at three pint on the cable. The grounding locations are as follows: RFP 5343
Exhibit 2
a) Immediately outside the cable entrance to the equipment room, shelter, or building. This ground is attached prior to the phaser type lightning suppressor. b) At the bottom of the vertical run of cable, at a point near and above the bend onto the ice‐
bridge or support trestle. This grounding point should be as near the ground as possible. c) The top end of the vertical cable run near the termination or antenna. This point is grounded or bonded to the tower by means of the clamp supplied as part of the grounding kit. All three points should be grounded in accordance with the recommendations provided in the grounding kit instructions. These instructions are included in kits similar to the Andrew type 204989 or equivalent. 2.6 Coaxial Suppressor Poly‐Phaser type IS‐B50 or equivalent lightning suppressor should be installed near the inside cable entrance of the building or communications shelter. This suppressor should be bonded to the nearby ground bus plate to remove surge current from the center inductor of the cable. 2.7 Tower‐Top Preamplifiers Poly‐Phaser type IS‐GF50 surge suppressor should be installed according to the manufacturer’s instructions as an additional protective measure at the input ports of the tower‐top amplifiers or preamplifiers. This protection is in addition to the DMEC internal amplifier protective devices. All tower‐top preamplifier chassis must be grounded to the tower. Where possible, DC ground shunt‐fed antennas should be used as additional protection for the tower‐
top preamplifiers. Antenna cable attachments to the antennas are to be kept as short as possible. In cases where tower‐top amplifiers are employed that use DC supplied via the coaxial transmission line, DMEC will ensure that an impulse suppressor similar to the PolyPhaser IS‐GC50 DC injection type is used. Certain tower‐top amplifiers are already equipped with this protection. 2.8 Tower‐Mounted Microwave and Repeater Equipment For tower top repeaters, the input and output points are the most important to protect. Tower, telephone or control lines are often overlooked. Coax line protectors are employed in the DMEC repeater inputs and outputs, and the preamplifier front end. Power line protectors must be local and single point grounded at the top with the equipment. The need for power protection is doubled for tower top repeater and preamplifier installations where 120 or 240 VAC is being fed up the tower. Above 18 GHz, microwave equipment usually has a Gunn down converter located on the back of the dish, being powered through one or two coaxial lines. These lines also handle the uplink and down link frequencies as well as Automatic Frequency Control (AFC) error information. RFP 5343
Exhibit 2
Protectors similar to the Poly‐Phaser IS‐MD50LNZ should be employed at the top and bottom to properly protect the equipment. A device similar to the PolyPhasor IS‐DC50LNZ is another type of protection used in these application and if fully transparent to all existing voltage and signal from microwave equipment. 2.9 Communications Equipment Room Internal Grounding A Halo ground should be employed inside the communication shelter. This Halo ground must be installed in the form of a “ring” in such a manner as to enable the use of short length conductors attached from the equipment racks, cabinet, cable trays, and equipment shelves to the ground ring (Halo). This Halo is made of number 2 AWG stranded copper wire attached to standoffs at approximately eight (8) feet above the equipment room floor. Where the room or communication shelter has less than 100 feet of perimeter, a minimum of four (4) ground risers are used. In any case, where possible, a ground riser is used at each corner of the perimeter. In installations where the perimeter of the equipment room exceed 100 feet perimeter, a ground rise will be attached at ever twenty (2) feet of perimeter. These ground risers are made of number 2 AWG SOLID copper which exits the room, or building via poly‐vinyl conduits (PVC). Grounding of Equipment Cabinets, Racks, and Shelves Each equipment cabinet or rack shall be equipped with a ground bus that is attached to the halo ground and the external system ground. Each equipment chassis secure in a cabinet or rack is connected to the cabinet or rack ground bus. Equipment mounting rails are the preferred ground connection points within the cabinet or racks. Attachments from the equipment cabinets and enclosures to the internal ground halo are made using number 6, or larger, stranded copper wire. Connections from these enclosures to the halo ground will be made using the shortest path length to diminish inductance. Cable Trays Cable trays will be attached to the internal ground halo via number 2 AWG, or larger, stranded copper wire. Where mechanical connections (lugs, bolts) are made to interconnect cable tray section an additional connection will be employed between cable tray sections to ensure a good electric ground connection. Number 6 or larger, stranded copper wire will be used. Grounds between cable trays, equipment cabinets, equipment racks, and AC utility power enclosure will be via number 2 AWG, or larger, stranded copper wire. When compression type connectors are employed at a DMEC installed site or system, the Burndy compression system shall be used. This system consists of connectors for taps, splices, cable to ground rod, and structural termination. These connectors may be used in some DMEC sites ground RFP 5343
Exhibit 2
applications. The Burndy system connectors are listed with Underwrites Laboratories Under Standard UL467. Most connectors have been successfully tested according to the requirements of IEEE Standard 837. Part 3 – PLANS AND DOCUMENTATION Drawing and Ground reference documentation will reflect the following items: a) Grounding and bonding plan b) Ground rod c) Surge suppression devices d) Bulkhead panel types e) Coaxial cable grounding kit(s) A prepared plan for lightning and surge protection measure implement into DMEC communications system is submitted as part of the overall system specifications. This plan takes into account such items as the radio installation and equipment to be protected and local conditions. This plan must meet all requirements covered in this specification, unless a specified written waiver is provided by the customer and agree by DMEC. RFP 5343
Exhibit 2
APPENDIX C BUILDING SCHEMATIC
RFP 5343
Exhibit 2
8
7
6
5
4
3
2
1
H
H
G
2 inch PVC
Sleeve
G
TELCO
Demarc
GFI
2 inch PVC
Sleeve
F
F
4 port X 3 port
Entry - 4 inch
APPENDIX C
HVAC
24.5" X
42"
E
E
Ground Bar
(inside & out)
HVAC
24.5" X
D
D
42"
GFI
C
C
B
B
DENTON MUNICIPAL ELECTRIC
COMMUNICATIONS BUILDING DESIGN
SPENCER
A
SIZE
FSCM NO
1/4" = 1'-0"
SCALE
8
RFP 5343
Exhibit 2
7
6
5
4
DWG NO
3
SHEET
2
REV
1 OF 1
1
A
SHELTER WORKSHEET
RFP 5343
Exhibit 2
DENTON MUNICPAL ELECTRIC
SHELTER WORKSHEET
Customer Name:
DENTON MUNICIPAL ELECTRIC COMMUNICATIONS
Site Name:
Spencer Tower Site (next to Spencer Generating Plant)
Site Address:
1701A Spencer Road
City:
DENTON
TX
State:
76205
Zip:
Technical Contact
Name:
Darrell Washington
Business Telephone: (940) 349‐7311
1. Structural Options
Qty
Shelter Size
W 9
X L 20
X H 9
(feet)
1
inside dimensions nominal
Stuctural Openings
Waveguide Feed‐thru Plate
H 4
X V 3
ports
1
Floor Cable Entry Slot
PVC Sleeve Opening
2
Additional Rectangular Openings
2. Architectural Options
Qty
Exterior Finish
Aggregate concrete
Steel Door
W 3
X H 8
(feet)
1
Bullet‐Resistant Door
SPSA/44 Mag
1
HPR/30.06
Door Accessories
Deadbolt Lock
1
Lock guard (pick plate)
1
Hydraulic Door Closer
1
Door Canopy
W 3
X H 3
(feet)
Interior Options
Insulation, wood panel fiberglass reinforced plastic
R‐12
RFP 5343
Denton Municipal Electric Confidential
Exhibit 2
R‐18
R‐22
8/14/2013
X
1
DENTON MUNICPAL ELECTRIC
SHELTER WORKSHEET
Floor tile
1
Sub‐floor
W
X H
(feet)
Partition Walls Doors W
X H
(feet)
Partition Walls
Folding wall desk, 16 inch X 20 inch
File Cabinet
2 Drawer
4 Drawer
3. Electrical Systems
Qty
120/240 VAC, 60 Hz single‐phase
1
120 VAC, 60 Hz three‐phase
Generator Recepticles
100 Amp
200 Amp
1‐Phase
3‐Phase
Other (Specify)
Generator Mating Plug
100 Amp
200 Amp
1‐Phase
3‐Phase
Uniterruptable Power Supply
18
Other (Specify)
kVA
1
Ground Fault Interrupt Recepticles
2
Additional duplex recepticle, 20A/120V, 60 Hz
6
Additional AC recepticle, 20A/240V, 60 Hz
Additional Circuit Breakers
Amp
Qty
Amp
Qty
1‐pole, 240 V
/
/
2‐pole, 240 V
/
/
3‐pole, 240V
/
/
Lighting Systems
Additonal flourescent, 4 foot, two tubes
6
Wire guard for flourescent fixture
Acrylic prismatic lens for flourescent
6
Additonal incandescent, 100 watt
1
Emergency lighting, 7.5 Watt
EXIT SIGN
Photocell
1
Switches and Controls
RFP 5343
Denton Municipal Electric Confidential
Exhibit 2
1
8/14/2013
DENTON MUNICPAL ELECTRIC
SHELTER WORKSHEET
Timer
minute
hour
200 Amp
1‐Phase
3‐Phase
200 Amp
1‐Phase
3‐Phase
Manual Safety Switch
100 Amp
Manual Transfer Switch
100 Amp
4. Grounding/Lighting Protection
Qty
Ground Bar System
2
Halo Ground System
1
Perimeter Ground Bus System
External Ground System
Ground Drop (equipment)
Ground Bar
1/4 inch
X L
24
XH
4
(inch)
Conduit Grounding
Faraday Cage
Surge Arrester
Primary Arrester
Alarms
1‐Phase
Secondary Arrester
3‐Phase
Alarms
1‐Phase
3‐Phase
5. HVAC System
Qty
Air Conditioning
Wall Unit
BTU/H
X
1‐Phase
3‐Phase
2
Heater
Heat Strip
Watts
Economizer & heat strip
Watts
Lead/Lag Timer
Window Unit
1
BTU/H
Heating Systems
Forced Air Heater
Watts
Electric Baseboard
Watts
Ventilation Systems
RFP 5343
Denton Municipal Electric Confidential
Exhibit 2
8/14/2013
DENTON MUNICPAL ELECTRIC
SHELTER WORKSHEET
Fan Ventilation System
CFM
1
Economy/Emergency Thermostat
1
Battery Vent System
6.Cable Ladders/Wireway
Qty
Cable Ladder
6 inch W X
feet (L)
Gold
Gray
feet (L)
Gold
Gray X
1
feet (L)
Gold
Gray X
1
feet (L)
Gold
Gray
Cable Ladder
12 inch W X 9
Cable Ladder
18 inch W X 20
Cable Ladder
24 inch W X
Wireways
4 inch X 4 Inch
10 ft section
4 inch X 4 Inch
5 foot section
4 inch X 4 Inch
1 foot section
4 inch X 4 Inch
90° elbow
4 inch X 4 Inch
tee section
4 inch X 4 Inch
closing plates
7. Safety/Security Options
Qty
Alarm Systems
Mounting Board (telco/alarm)
1
Terminal Cabinet
Open‐door Alarm
1
Smoke Alarm
1
High‐temp Alarm
1
Low‐temp Alarm
1
Humidity Alarm
High
Low
Power Failure Alarm
1‐Phase
X
3‐Phase
Air Conditioner Failure Alarm
RFP 5343
Denton Municipal Electric Confidential
Exhibit 2
1
1
8/14/2013
DENTON MUNICPAL ELECTRIC
SHELTER WORKSHEET
Safety/First Aid
Battery Room Safety Kit
1
Emergency Eye Wash Station
1
First Aid Center
1
Fire Extinguisher
Type CO2 Class B:C
Lbs.
5
1
Fire Extinguisher
Type CO2 Class B:C
Lbs.
10
1
Fire Suppression System
8.Spare Parts
Qty
9. Transportation and Additional Services
DMEC
Vendor
Qty
Transportation by:
X
1
Off‐loading:
X
1
Site Setup
X
1
Civil Work & Site Preparation
X
1
RFP 5343
Denton Municipal Electric Confidential
Exhibit 2
8/14/2013
SCHEDULED INVENTORY OF EQUIPMENT TO BE PLACED INTO THE BUILDING RFP 5343
Exhibit 2
DENTON MUNCIPAL ELECTRIC
COMMUNICATION INVENTORY SHEET
Site:
Spencer Generating Plant
Description
Motorola Quantar RF Repeaters
RF Combiners (for 2 transmit antennas)
RF Multicouplers (for receiver antenna)
Motorola Trunking Controller (MTC3600)
GE Junglemux Fiber Multiplexer
Ethernet Switch
RFP 5343
Exhibit 2
Qty
100 watt
14
2
1
1
1
1