Transcript
TRANSPORTATION DEPARTMENT
Development of Installer’s Working Plans
111 Deerwood Road, Suite 200 This is a “sterilized” version of a report that was delivered to a client. San Ramon, State 94583 (925) 552-0802 Connect802 installed Wi-Fi wireless network systems at www.Connect802.com school district transportation facilities from California to
[email protected] Georgia under a national contract.
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On-site noise and channel assessment and a detailed physical site assessment provided the basis for these report plans that were used by the installers during the truck rolls. 0
CONNECT EZ™ RF ANALYSIS SERVICES Wireless data networks transfer packets of information by representing bits using specifically defined fluctuations in a transmitted carrier signal. To properly assess the characteristics of a site it’s necessary to evaluate both the data being transferred and the radio signals being transmitted transmitted. Packet-level analysis tools are used to evaluate data and spectrum analyzers are used to evaluate the RF environment and transmitted signals. Because of the complexity of RF signal analysis and the cost of spectrum analyzers it’s common to find that a proper RF survey may have never been performed at a particular site. That’s where the Connect EZ Services are applied for RF spectrum analysis, channel and noise assessment, system troubleshooting, and pre-installation site assessment. This report presents the conclusions drawn from the on-site RF analysis and a complete set of Installers Plans in preparation for the equipment installation. It is assumed that the reader is suitably familiar with RF-related issues and that the installer is suitably trained and experienced in the required skills.
Disclaimer and Perspective on RF Analysis Any radio system may experience problems related to unpredictable or unanticipated RF interference, noise, or other spectral events. Connect802 does not warranty or guarantee any work, or equipment usability, when such situations arise. In all cases, Connect802r's liability will be limited to a refund of all monies paid by the customer. Connect802 will perform all RF consulting work in a professional manner and will attempt to correct, at no cost to the endcustomer, oversights that may arise in conjunction with a project. This assurance does not extend to problems resulting from unexpected, or unnoticed characteristics of the RF environment at the customer's site. Connect802 will work towards solving problems that may arise out of RF spectral events but these services (or products) may be quoted and billed as additional work on a project, subject to the customer's approval. Customer's may opt to include a full Faraday Cycle Analysis as part of their pre-installation design work. Every effort has been made to provide accurate, reliable information and to draw valid conclusions. If you base any decisions on the information in this document, or on any other discussions with the RF engineering, sales or management team, you accept all liability for consequences arising from those decisions. You must consider the following points when applying the contents of this document to anything: Component data are extracted from catalogs, brochures, and web page material provided by various vendors. Component specifications may change without notice and individual manufacturing tolerances, equipment damage, or incorrect installation may result in variations from published equipment specifications. The RF environment is subject j to influences that may y not be anticipated. p Findings g p presented in this report p reflect the state of the RF environment at the time the measurements were taken. Every effort has been made to confirm that the measurements are representative of the typical state of the environment but that environment may change without any obvious visible indication. Information obtained from subject matter experts and other authoritative sources may be used without independent validation and may be inaccurate. The electromagnetic characteristics of any space are affected by a variety of complex interactions ranging from the 11-year sun spot cycle to microwave ovens and cordless phones. It is impossible to anticipate or evaluate all of possible environmental influences that may y cause the conclusions in this document to be invalid. the p If you base any decisions on the information contained in this document you acknowledge that you have carefully considered the potential for error and you accept that risk. The data in this report is provided on an as-is basis with no warranty or guaranty for accuracy. No warranty, express or implied, is made concerning consistency with any standard of merchantability, or that the information provided will meet your requirements for any particular application. The information in this report must not be relied upon for implementing a transmission system whose incorrect d i design, installation, i t ll ti or use could ld result lt in i injury i j to t a person or loss l or damage d to t property, t including i l di but b t nott limited to intellectual property or computer data. Connect802’s liability shall be limited to a refund of all monies paid to obtain this report and there shall be no liability for loss or injury caused by Connect802’s actions, omissions, or for contingencies beyond its control nor for decisions made or action taken or not taken in reliance upon the information furnished in this document. Connect EZ™ Services
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EXECUTIVE SUMMARY Overview of the Site Survey Connect802 dispatched an RF engineer to the installation site. During the on-site on site engagement, the following work was completed: • Perform an RF spectrum analysis throughout the entire site area to ascertain whether any unacceptable levels of environmental noise or interference would negatively impact the specified wireless communication system. A full suite of measurements was evaluated in real-time to explore potential problems and the analysis data was captured and recorded for further off-site off site examination. Measurements and spectrum sweeping included industry standard best-practice techniques utilizing: – – – –
FFT (Fast Fourier Transform) waveform display Duty Cycle analysis Swept Spectrogram recording and evaluation for both FFT and Duty Cycle Identification of the spectral signatures for interferers, noise events, signal reflection, and existing transmitter channel overlap.
• Q Quantify tif and d evaluate l t existing i ti Wi-Fi Wi Fi networks t k operating ti in i th the same ffrequency band b d as the proposed system and visible within the intended wireless coverage area. • Study the effects of destructive and constructive RF signal reflection and the impact of multi-path attenuation caused by the presence of flat, metal sides and curved roofs on parked busses and metal building exteriors. • Look for potentially disruptive sources of EMI (Electro-Magnetic Interference) from transformer vaults, electrical machinery, arc-welding equipment, mercury-vapor lighting, and other sources. • Search for the presence and measure the impact of intentional transmitters causing random noise or coherent interference at the site including equipment similar to the following: – – – – – – –
2.4 GHz cordless phones Wi l Wireless computer t kkeyboards b d and dh headsets d t Nearby airport radar Wireless gate and door access controls Handheld and vehicle-mounted 2-way radios RFID interrogators and wireless bar-code scanners GPS transponders
• Exhaustivelyy explore p and document the requirements q for equipment q p installation and cabling including restrictions, caveats, areas of concern and complete measurements with accompanying photographs.
The present report details the conclusions of the on-site work, provides a complete set of Installers Plans, and lists any special equipment or tools that will be needed by the installer. Connect EZ™ Services
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SUMMARY OF TEST RESULTS Received Signal Strength Test: Mi i Minimum measured d signal i l strength t th d during i on-site it survey: Specified minimum target signal strength: Specified maximum environmental fade allowance: Specified worst-case signal strength:
EXCELLENT -78 78 dB dBm -79 dBm 10 dB -89 dBm
PING Data Transfer Quality Evaluation: Minimum Response Time: Maximum Response Time: Average Response Time: Lost Packets:
EXCELLENT 1 ms 68 ms 4 ms < 1%
RF Spectrum Analysis Environmental Quality Assessment: General assessment of the 2.4 GHz operating environment: General assessment of the 5.8 GHz operating environment: Average Interference and Noise Level: Expected Carrier-to-Interference-and-Noise-Ratio (CINR): Interferer Duty Cycle (Typical):
VERY GOOD Good Excellent -100 dBm 22 dB < 1%
802.11 Channel and Noise Assessment: Active 802.11b/g Channels: Number of Active 802.11b/g Access Points: Typical Range of Interferer Power 802.11 Channel Quality:
GOOD 1,2,5,6,7,8,11 10 -85 dBm Excellent
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EQUIPMENT CONFIGURATION The Colubris Ruggedized MultiService Access Point Th Wi-Fi The Wi Fi system t utilizes tili a commercial-grade i l d C Colubris l bi MultiService Access Point (MAP). These are specifically designed to provide the industry’s most comprehensive feature set among enterprise-class access points. The Colubris MAP automates the configuration and operation of the RF network to facilitate remote management and control. control Channel and Power Settings The Colubris MAP can be configured to automatically select a channel within the desired frequency band based on an interference scan. The channel selected minimizes both interference from other transmitters experienced by the MAP and potential interference to other transmitters caused by the MAPs transmissions. In the present design the automatic feature will not be used. This is because of random noise spikes attributable to the electric power substation adjacent to the bus lot. It is reasonable to assume that automatic channel selection may occur during a moment when the sporadic noise bursts are not occurring. Hence, the MAP could select a channel that appeared to be quiet only to have noise occur during actual use. The automatic feature scans at fixed intervals, not constantly. To mitigate this possibility the MAP will be configured to operate on a fixed channel (Channel 6) which was found to have minimum noise. Channel Configuration for the Present Installation The Colubris MAP will be configured to operate on 802.11b Channel 6 to avoid the most severe noise bursts observed from the adjacent electrical power substation. Power output will be set to maximum (18 dBm +/- 2 dB). The design utilizes a 9 dBi omnidirectional antenna with a 7 degree electric downtilt.
The specially p y designed g omnidirectional antenna has a 7 degree electrical downtilt to the propagation pattern causing the radio signal to be directed downwards, towards the busses in the yard, instead of predominantly outwards, over the tops of the busses. Connect EZ™ Services
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DESIGN SPECIFICATIONS Overall Considerations The site design g created for this p project j will p provide a minimum -89 dBm to meet the specifications listed below. This minimum target takes into consideration the potential for as much as 10 dB of environmental fading, hence the on-site survey targets -79 dBm as the minimum acceptable signal level across the intended coverage area. Developing a correct design often involves a trade-off between alternatives available to the RF engineer. The present design is based on a moderate coverage strategy in which engineering compromises were resolved based on practical usage assumptions assumptions.
Customer-Designed Proprietary Wi-Fi Receivers The present design supports the proprietary 802.11b client devices which have the following specifications: Transmit Power Output (TPO)
30 mW (14.7 dBm)
Receiver Effective Antenna Gain
2 dB
Effective Isotropic Radiated Power (EIRP)
16.7 dBm
Mi i Minimum Modulation M d l ti Rate R t
5 5 Mb 5.5 Mbps (802 (802.11b) 11b)
Minimum Required Receive Signal Strength (RSSI)
-89 dBm
Fade Margin
10 dB
Maximum Modulation Rate (0 dB Fading)
11 Mbps @ -80 dBm
Colubris MAP-330R Dual Radio Outdoor Access Point The central Wi-Fi access point for the system has the following specifications: Air Standard
802.11b
T Transmit it Power P Output O t t (TPO)
70 mW W (18 (18.5 5 dB dBm))
Transmitter Effective Antenna Gain
9 dBi
Effective Isotropic Radiated Power (EIRP)
27.5 dBm
Minimum Required Receive Signal Strength (RSSI)
-94 dBm
Mi i Minimum Modulation M d l ti Rate R t
1 Mb Mbps (802.11b) (802 11b)
Maximum Modulation Rate (0 dB Fading)
11 Mbps @ -85 dBm
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RF SPECTRUM ANALYSIS
AVG <-100dBm
Noise Bursts
Noise Bursts Ch8
Adjacent j Power Sub-Station Noise Adjacent to the bus parking area on one side of the lot is a power sub-station. The photo to the right shows the spectrum analyzer in the foreground and the substation in the background. The hum of the high voltage wires can be heard throughout this corner of the bus lot. Careful attention was paid to this area to confirm that the level of background electromagnetic interference would not cause problems with the Wi-Fi system. The FFT display (upper right) shows some noise spikes (yellow spikes) but they are random in nature and the average noise level (purple trace) remains below -100 100 dBm. The Duty Cycle and Swept Spectrogram graphs show that the most significant bursts of noise occur outside the Channel 8 frequency range and the Wi-Fi system will be configured to operate on Channel 8 for noise avoidance. Ping testing confirmed that the noise did not create undue degradation in the system. Connect EZ™ Services
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Major Yard Areas Were Free of Significant Noise or Interference Although the area adjacent to the power substation experienced RF noise (previous page) the remainder of the yard was generally free of the EMI noise spikes. Occasionally a nearby 802.11b Wi-Fi access point momentarily appeared
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802.11a 802 11 5.8 5 8 GHz GH B Band d was V Very Q Quiet i t The wireless backhaul link between the transportation office (where the On-Site Audio Server will be installed) and the roof of the public works sand shed (60 feet tall, 100 feet away) will be implemented using an 802.11a WDS link operating in the 5.8 GHz frequency band. The FFT trace above shows that average noise is roughly -110 dBm and the maximum signal levels observed (blue trace) effectively remain at and below -100 dBm. The environment for the backhaul link is excellent.
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EXISTING ACTIVE TRANSMITTERS Engineering Perspective A Wi-Fi receiver is essentially unable to recover a data transmission when the received signal i l power iis lless th than roughly hl -95 95 dB dBm. A d desired i d ttransmission i i mustt also l b be att least 5 dB stronger than any other transmitters present in the environment. Ideally, this difference (the Signal-to-Interference Ratio, SIR) should be closer to 20 dB in an ideal situation. As seen below, a single access point (00026F3530A5) is visible on Channel 8 (along with the survey AP), but is not broadcasting its SSID. It is only visible in some limited areas throughout th h t th the yard. d Th The choice h i off Ch Channell 8 tto minimize i i i noise i iinterference t f iis not impacted by the presence of this single access point interfering (to a limited degree) on the channel. Signal strength in the yard will typical by between 10 dB and 15 dB stronger than that of the other Channel 8 device. It is not anticipated that the other transmitters in the vicinity will impact the performance of the specified system.
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RF SIGNAL STRENGTH TESTING Testing Confirmed That Signal Levels Were At and Above the Specified Levels A test transmitter was p placed at the location denoted with the yyellow circle in the site map p below. Signal strength measurements were obtained at various locations throughout the intended coverage area. The measurements indicate the expected signal power that will be received from a specified transmitter when the signal arrives back at the Colubris access point. The worst-case measurement (-78 dBm) is indicated with a dashed box. Note that the -84 dBm measurement is actually outside the desired coverage area but remains viable for connectivity.
Additional Active Bus Parking in this Area
-74 dBm 4 dB
End of Required Coverage Area
-71 71 dBm -78 dBm
-56 dBm
-84 dBm
-51 dBm -67 dBm -74 74 dB dBm
-65 dBm
- Test Transmitter Location Tx Power: 14.5 dBm Test Antenna: 5 dBi Antenna to be Used: 9 dBi Adjustment Shown: +4 dB
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DATA TRANSFER TESTING Overview of the Testing A continuous PING data transfer test was performed while walking in a complete circuit around the yard yard. The graph below shows the PING response times times. PING response times less than 5 ms (dashed green line) indicate that no packet loss was encountered. Other PING response times imply that the transmitter required two or more attempts before successful data transfer was achieved. The 802.11 standards consider up to 16 retransmission attempts to be within normal operating limits and for up to 30% of traffic (worst-case) to experience one or more retransmissions. PING transmission attempts which failed (“lost ( lost packets packets”)) are indicated by the “REQUEST REQUEST TIMED OUT” OUT arrow. arrow In practice practice, the higher-level TCP/IP retransmission mechanism will automatically resend lost 802.11 packets guaranteeing successful transfer of data. 802.11 retransmissions and occasional lost packets have an impact on data transfer rates, not on the success of the data transfer process. Conclusions It can be seen that almost all PING replies were less than 5 ms. The various longer PING replies and the three lost packets occurred in a random manner manner, consistent with environmental noise corruption. Overall, this level of performance is highly consistent with that which would be expected in any outdoor environment and does not appear to be significantly influenced by any undue level of electromagnetic interference. The PING testing was performed on Channel 8, the same channel on which the system will operate. The RF environment introduces no data transfer issues that would be visible to the performance of the specified system. system Packets: Sent = 213, Received = 210, Lost = 3 (1% loss), Approximate round trip times in milli-seconds: Minimum = 1ms, Maximum = 68ms, Average = 4ms REQUEST TIMED OUT
Response Tim me (ms)
GRAPH SIZE PLACEHOLDER
5 ms Connect EZ™ Services
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SITE PHOTOGRAPHS Sand Storage Building
Shown from three vantage points are the modular building where the On On-Site Site Audio Server will be installed (and on which the single-radio MAP will be installed) and the tall sand-storage building on which the dual-radio MAP will be installed. The arrows show the orientation of the photograph.
View From Vi F Behind B hi d the th Transportation Office Seen below is the view from behind the Transportation Office, looking across the fueling area towards the sand-storage building (seen in the background.) Transportation Office
More Bus Parking Behind This Building Electric Power Substation
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INSTALLATION OVERVIEW IMPORTANT NOTE: A man-lift will be required to reach working heights of 55 feet CAT 5 Outdoor-Rated O td R t d Ethernet Eth tC Cable bl R Run (i (including l di margin-of-error): i f ) Antenna Transportation Building: From equipment shelf up into dropped ceiling 7 Feet Across main office area 27 Feet Antenna Down the hallway 30 Feet Lightning To front of building and out to the MAP 20 Feet Arrestor Cable length to allow for transportation bldg: 95 Feet Sand Storage Building: Colubris From receptacle to front of building 12 Feet Access Up the tall wall to the MAP 60 Feet Point Cable length to allow for sand storage bldg: 85 Feet TOTAL CABLE LENGTH REQUIRED 180 Feet GROUND WIRE LENGTH REQUIRED 15 Feet Top View
Transportation Building: Outdoor-rated Ethernet cable runs up from the equipment shelf, across the d dropped d ceiling, ili and d egresses the th building b ildi att the th MAP. MAP Sand Storage Building: The cable runs from the receptacle, to the front of the building, then up the tall wall to the MAP.
PoE Injector On-Site Audio Server Notebook Computer
USB-Ethernet Adapter
Door
CAT 5 Patch Cable to Customer’s Internet Connection
Front View Connect EZ™ Services
DIAGRAMS ARE NOT TO SCALE
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Synopsis of System Installation The antenna is mounted to the top of the mast. The Colubris access point is mounted at the base of the mast, 6” above the roof edge or top “Y” mounting bracket (when used.) A lightning arrestor is attached directly to the Colubris antenna connector and grounded t an appropriate to i t lightning li ht i ground d point. i t [Note: For this connection, use the MAIN or RADIO 1 antenna connector on the Colubris. Attach one of the supplied “rubber duck” antennas to the other connector (AUX or RADIO 2) if that connector is otherwise unused.]
A drip loop is formed in the antenna cable at the access point and all antenna connectors are weatherproofed using vinyl and rubber mastic tape. A drip loop is formed in the Ethernet cable at the point of exterior wall penetration penetration. The point of penetration is weather-sealed. The outdoor-rated Ethernet cable is run to the wiring cabinet where it attaches to the PWR+DATA OUT port of the PoE injector. The injector is plugged into a 110VAC source (which does not have to be UPS protected.) The DATA IN port of the PoE injector is connected to the On-Site Audio Server using a bl cross-over Eth Ethernett cable. The On-Site Audio Server and USB-Ethernet Adapter are shipped separately after the wireless system has been installed and tested.
PoE Injector
Antenna mounted to top of pole with U-bolts (supplied with antenna) Lightning Arrestor with #6 copper ground wire Access Point mounted 6-inches above the roof
Lightning Arrestor with Grounding Bracket
On-Site Audio Server Notebook Computer
3’ Ethernet Crossover Patch Cable
Outdoor-Rated O td R t d Ethernet Cable Being Installed Up to Access Point
Drip Loop
PoE Injector 6’ CAT 5 Patch Cable To Customers Internet/WAN Connect EZ™ Services Connection
USB-Ethernet Adapter
Injector Power Adapter 14
INSTALLER’S WORKING PLANS The On-Site Audio Server will be installed in the transportation office which is housed in a modular building at the side of the lot. The public works department leases space on the property t and d has h constructed t t d a 65’ ttallll b building ildi tto cover th the llarge pile il off road d sand d used d in the winter. The second antenna will be mounted on the roof of the sand building. NOTE: The roof edge of the sand building is between 50’ and 65’ AGL. A man-lift with a 65’ reach will be required. (There is suitable flat concrete below the work location for the maneuvering and placement of the lift.)
Sand Storage Building This building is a high-roof structure, open on the right-hand side, in which a very large pile of sand is stored for sanding roads in the winter. The left-hand side of the structure has a slightly lower roofline and interior storage area. The Th main i antenna mast will be mounted on the front face of the lower roof section, roughly 50’ above the ground.
Office Modular Building A single-radio MAP will be installed on the exterior of this building, facing the sand storage building
- Antenna Location Connect EZ™ Services
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A single-radio Colubris MAP (shown in its mounting configuration) will be installed to the face of the transportation building at the location depicted by the orange square. The unit must be mounted at a height that gives a clear line-of-sight to the roof of the sand building without being obstructed by the overhanging eave. The lineof-sight should be from a point 6” above the tip of the MAP antennas. It’s estimated that this will result in a point roughly 12” to 18” below the roof edge. g Based on field observations at the time of installation, install the MAP as high as possible while retaining the line-of-sight.
Line-of-Sight out from under eaves up to sand building roof antenna
Inside the building, the equipment shelf is located in the far back corner. The On-Site Audio Server and PoE injector will be installed here here. The cable will go up into the dropped ceiling, run across the building, and exit the building at the point of MAP installation. The office area is open and tiles can easily be removed d tto run the th cable bl across th the ceiling ili from the back corner to the front opposite corner where the MAP will be installed. Note: Because this antenna is below the eave of the building and due to its small form factor, lightning arrestors are not required.
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The main antenna will be installed on the garage end of the sand storage building as shown by the overlay diagram on the top photo. This building is owned by the County and the space p p permission will be required q to p perform work on this is leased from the District. No special building and the District IT person has keys to the building for unrestricted access. Note that the peak of the roof near the antenna is roughly 60’ above the ground so a highreach man-lift will be required.
Antenna
For p perspective, p , the air vents at the top of the sand storage area are shown from the sandside and from the outside.
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Roof Line Where Lower Roof Connects
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The MAP mounted to the front of the office building will have its standard 5 dBi Rubber Duck antennas used (Main and Aux with diversity active). At 5.8 GHz these dual-band antennas provide roughly 3 dB gain with a 30 degree vertical beamwidth. Link gain of 7 dB is required p Fresnel radius is 3 feet. At the edge g of the high g roof (20 ( feet from the and the 60% mid-point peak) the 60% Fresnel radius is 1 foot. The slope of the roof is such that mounting the antenna 10 feet to the right of the peak will both maintain Fresnel clearance and will keep the antenna within the 30 degree vertical beamwidth of the Rubber Duck on the office building.
6’ atan(46/150)=170
40’
25’
125’
tan(170)*125’=38.3’ MOUNTING LOCATION: 10 feet right of the roof peak
55’ AGL atan(40/140) = 150
Δ=40’ 140’
10’
The offset of the office building relative to the sand storage building requires the placement of the antenna as specified here. Mounting on the face of the sand storage building would put the antenna in the shadow of the building. Connect EZ™ Services
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The antenna is mounted to the outside of the building using three Y-brackets. The MAP is attached to the antenna pole.
Antenna 55’ AGL
By studying the bottom two photographs (which have been placed together for perspective) the interior configuration of the building at the office/storage room can be understood. When you enter the room you see the existing AC receptacle on the wall. This is where the PoE injector will be mounted and plugged in. There is no dropped ceiling over this space. When you look up you’re looking 50’ over your head to the exterior roof of the building. building It will be possible to maneuver up to a 30’ extension ladder into the room but it is not possible to work in this area with a man-lift. INSTALLING THE CABLE: The Ethernet cable will be installed by feeding the cable into this space from the outside. The cable will drop to the height that is accessible using an extension ladder inside the space. From the highest point that can be reached f from the th ladder, l dd the th cable bl will ill b be ffed d behind the steel I-beams and fastened appropriately to the wall. The key aspect of fastening the cable is to provide strain relief for the weight of the cable against the point where it enters the building. A small degree of slack should be introduced between the topmost attachment point and the entry point to avoid any possibility of chaffing through the entry hole. The cable is fed down the wall, across the top of the horizontal wall section at the bottom, and connected to the PoE injector.
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Office/Storage Room Door
This is what you see when you stand here and look up AC receptacle for PoE Injector
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The directional panel antenna on the mast will be positioned with the correct downtilt prior to mounting. When installing the mast it is necessary to rotate the mast so that the directional antenna is most closely aligned with a line-of-sight line to the radio on the transportation building building. The mast will be a 10’ 1-1/4” galvanized steel pipe with 4’ below the roofline and 6’ above. Three 12” Y-brackets will be used for mounting. The top and bottom bracket will utilize an angled leg brace for vertical support. IMPORTANT NOTE: The radio on the transportation building must be installed first. A link connectivity test will be performed on this assembled antenna mast (to the radio on the transportation building) prior to mounting this assembly assembly. After mounting mounting, the link connectivity test will be repeated prior to removing the man-lift from its work position on the ground. Grounding of this antenna will be to an interior building I-beam.
Directional panel will be pointed at radio on transportation building
55’ AGL
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HILTI METAL WALL FASTENER The HILTI brand metal wall fastener (sold through Home Depot) is used to install antenna mounting brackets to metal buildings when it is impractical or impossible to access the back side of the wall to install back bracing. Wh the When h b back k side id off the h wallll iis accessible ibl then a section of Unistrut can be installed as a structural brace behind the antenna bracket. When the back side of the wall is inaccessible then there is a concern that sheet metal screws, residential-grade hollow wall fasteners or toggle bolts will not provide sufficient structural strength and will simply pull out during the first high wind. The HILTI brand metal wall fastener addresses these concerns by providing a 3/8” solid metal bar with a tapped bolt hole 3/8 into which the mounting bolts will be secured. The top picture shows the wall fastener assembly and bolt. After drilling a hole in the metal building the fastener is positioned to be inserted into the hole hole. Once behind the wall, the plastic arms are moved to make the metal bar rotate parallel to the wall. Now, when you pull back on the plastic arms the metal bar is drawn up against the back side of the wall wall. The tapped bolt hole is between the two plastic arms and becomes visible during installation.
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The Metal Wall Fastener
Step 1: Drill Hole oe
Step 2: Insert Fastener In Hole
Step 3: Use Plastic Arms to Orient Metal Bar 21
Step 4a: Push Hold-Back Plate Flush Against Wall With the metal plate held tightly against the back of the wall, slide the plastic Hold-Back plate forward on the plastic arms so that it fits into the h l th hole thatt was d drilled. ill d When the Hold-Back plate is firmly against the wall, and firmly holding the metal plate to the back of the wall, carefully break off the two plastic arms. They’re scored to break easily. When breaking them off, be careful not to dislodge the Hold-Back plate.
Step 4b: Hold-Back Hold Back Plate Is Now Flush Against Wall
Finally, thread your bolt through the antenna mounting bracket that’s being installed and then carefully hand-thread the bolt into the metal plate. The bolt goes through the center of the Hold-Back plate. Care is needed to catch the first threads to avoid breaking the metal plate free of the Hold-Back plate and loosing it behind the wall. Once the bolt is tightened by hand to as many turns as is practical, continue to carefully tighten the bolt with a Phillips screwdriver. Be careful not to exert a lot of pressure against the bolt until you feel the metal plate being pulled tightly against g the inside of the wall. The finished installation will provide a strong point of attachment with little likelihood of the bolt and metal plate pulling out through the metal side of the building. Note that when using metal wall fasteners it’s it s common practice to use more than the normally recommended number of antenna brackets to distribute the horizontal leverage load.
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Step 5: Carefully Break Off the Plastic Arms Leaving Hold-Back Plate Holding Metal Bar in Hole
Step 6: Put Bolt Through Antenna Mount and Carefully Hand-Thread the Bolt Into the Metal Plate
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POST-INSTALLATON LINK TESTING Upon completion of the installation, live data throughput testing will be performed to confirm that the system will support the required data rates for the specified equipment. A bi-directional data throughput test will be performed in the locations indicated below.
LOC #6
LOC #7 LOC #1
LOC #3
LOC #2
LOC #4
LOC #5
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