The magnetic field will couple to all nearby conductive materials. Please note the below grade interconnection of the bulkhead panel with the other elements which comprise the grounding system. I have 2 questions. Turn On Voltage of 150 Vdc. Grounding Solutions For existing towers, look at the ratio of surface areas and ground resistance. Your first line of defense is on the outside of the building. Handles 50 kA max. When asked what they do with the disconnected line(s), they usually respond that it is placed on the floor. If copper were joined to aluminum or copper to galvanized (hot dipped zinc) steel with no means of preventing moisture from bridging the joint, corrosion loss will occur over time. Dont stop short of a good ground plane. Buy Now: https://www.streakwave.com/polyphaserBuy Now: https://www.streakwave.com/transtector Another alternative is to install an active cathodic protection system. In either case, high quality protectors will dump the energy into the ground system. The site will be something of which everyone involved can be proud to say they were a part. PolyPhaser, known for its innovative, reliable, dynamic RF surge protection and filtering solutions, now offers a broad range of cables and connector caps to fit the specifics of your applications. If powering the Alloy receiver by DC voltage, the DC input requires additional surge protection input of 24 V DC (+/-). Copper such as C110 used in our equipment shelter coax cable entrance panels has been used for roofing, flashing, gutters, and downspouts. Your second line of defense is inside the building. This gives some percentage of improvement but it still must interconnect to conductive soil where it has both salts and moisture. Use joint compound on exposed applications of the TK clamps. By using single point grounding, your ham equipment will survive the hit to your tower. LEARN MORE Upgrade Your Fiber Network ALL points, tower, gear, antennas, and your home panel ground MUST be tied together so that ALL points rise together in a voltage spike and fall together with a voltage drop. Have them installed on everything for my home tower as well. Full credit is given to Polyphaser for this information. If you follow the recommended PolyPhaser method of using radials and ground rods that lead away from the tower base, guy anchors, and equipment building, the resultant distributed surface area and current must return through ever increasing ground distance/resistance. This will maintain all chassis at the same potential during the strike event and minimize chassis-to-chassis current flow. Bulkhead mount with bracket for grounding or mounting. Thus, the surge current will only ride on the outermost surface of the conductor. surge current. Also, a strike to the tower or building can produce a local ground potential rise with damage to your equipment from energy attempting to escape to the outside world through the ac secondary conductors. Reviews Other Info Shipping Polyphaser GT-NFF-AL DC Pass Gastube Protector DC-7000 MHz with 80 VDC Pass Voltage. Local ground potential rise (GPR) can be the source of damage to any equipment interconnected to the outside world. However, be aware that stainless steel is not a very good conductor. The EMT will act as a faraday shield from the towers magnetic fields and will minimize the amount of induced energy. Turn on voltage is a nominal 600V. to a product via email. If the riser is over 50 feet away, it may not be the best ground path to use. The protectors must be grounded to each other as well as to the tower ground. The buried ground system radials, used with ground rods to further disperse the strike energy, are also bonded to the rebar. Any surge energy arriving on the coaxial cable, power and control wiring, or inadequate equipment ground system could find a lower inductance path to ground through your equipment and conductive concrete floor. The phone connection at the street was blown apart and the lid blown 95 feet from the underground connection. Any particular reason why you use Alpha Delta for HF and Polyphaser for VHF/UHF ? The straps extra surface area reduces the inductance and the sharp edges allow for a high E field concentration forcing more charge into the soil. The primary problem here is the low surface-area contact of the round wire with the (round) tower leg. $122.99 PolyPhaser Coaxial Lightning Protectors Coaxial Lightning Protector, Bulkhead Mount, 1.5-400MHz, HF 3kW, VHF 500W, DC Block, UHF Female, 50 ohms, Each See More Specifications Estimated Ship Date: Tomorrow Would you rather pick it up? The more the strike energy is divided, the less there is to go to your equipment. If the coil cant handle the energy (half the coax surge energy is on the center pin), the coil will open up and the current will translate to a large open voltage source capable of arcing anywhere within the radio. However, if this requires the plate to be far from your equipment and if the magnetic fields of a nearby tower can easily couple into the interconnecting wires and cables, then the panel should be located close to your equipment. Polyphasers are standard equipment in many commercial and government radio systems. PolyPhaser's new fiber enclosure product line is designed to make field installation as simple as possible and address FTTx, fiber distribution networks and growing high-speed voice, video. In this case, due to the poor nature of the tower ground system, each of these J-bolts will actually share a significant amount of strike current which in turn will flow through the concrete. Polyphaser's GXTM Series Bias-T products are RF path protectors with an integrated, protected DC Bias-T function. I once blew the traps in my Mosley TA-53 but never had any problem with the Polyphaser gear. Solder connections, even torched silver solder connections will not last as long as the above. High pressure clamps provide a meshing of copper to copper since the material is soft (malleable). This technique can provide a profile of the lower layers relative to the first foot. I see that they have many models. For hole cut-out dimensions, see page 4 of this guide. The only time I have ever had a problem was when the protector was misapplied to the system (wrong power rating, wrong power rating, high reflected power, not-common grounding point, no weatherproofing). Document Number PEN1009:Galvanic action. For an even more effective connection, use copper strap in place of wire with the TK series clamp. (See the Noble Metal Table for a ranking of commonly used metals.). Infinite Electronics brand PolyPhaser has released a new line of fiber terminal boxes, splitter distribution boxes and rack-mount panels billed as ideal for use in communications, telecom, cable TV, surveillance and monitoring systems. The PolyPhaser Entrance Bulkhead serves as a low inductance entry ground, entry plate, and mounting point for PolyPhaser center pin protectors. An exothermic weld is created when a graphite mold around the connection is filled with copper oxide and aluminum powders. A gas tube will not be adversely affected by temperature, humidity, pollution, or wind, while the air gap will be affected. These installation instructions assume that the user is already familiar with the installation instructions and physical layout of the central control interface products. For Outside Installation: This unit is NOT weatherproof and must be sealed against moisture. An improperly grounded insulated guy anchor can arc through the anchors pitch coating, cracking the concrete with resulting structural failure. Another complication in this scenario is the inductance of the conductor between the I/O protector and the ground system. PolyPhaser IS-50UX-C0. Document Number PEN1024: Multiple I/O port protection,Single Point Ground considerationsNotes:One of the basic ideas in developing a protection strategy is not allowing stray energy to flow through the equipment. If your tower is close to the building, the recommended grounding strap, running down the outside wall, may inductively couple some energy from the tower. Please note the below grade interconnection of the bulkhead panel with the other e lements which comprise the grounding system. However, it is also necessary to be careful about voltages that may exist between the I/Os during a strike event. Even though the inductive properties of the coax cable appear to be beneficial, and extra inductance can be created by adding a few turns to the coax; dont do it. If the soil already has a sufficient amount of naturally occurring salts, adding water will free the ions and improve conductivity. Install additional bare radial lines with ground rods which will effectively parallel the inductance and reduce the overall system inductance. Document Number PEN1030:An interconnected concrete tower base can help the tower ground system. Tower mounted equipment is similar to the above high rise situation. I have 5 Alphe Delta switches with no problems. Most people think underground is better from a lightning standpoint. If a PolyPhaser Entrance Bulkhead with its two 6 inch [152.4 mm] copper straps were used in the previous example, the inductance path would be lowered to 2.7uH, and the voltage at the entrance bulkhead would be reduced to 5670 volts. &>1^jVGVRqW ;kMR2F$Zm5\[2+o^sw.Y The significance of being more noble means any other metal buried and connected to your copper ground system will be more anodetic and thus become sacrificial. We have tested this compound with a loose 1 square-inch (6.5 sq-cm) copper to copper joint and have found it to handle a 25,500 ampere 8/20 waveform surge with no flash over and no change in resistance (0.001 ohms). Another is to provide some form of impulse protector for each of the equipments Input or Output (I/O) ports. PolyPhaser offers a series of data and Telco protectors when a higher level of protection is required. If you have a antenna tuner fed long wire and the pole is just supporting the antenna wire, it would be a good idea to have the grounded straps extend higher to intercept a strike or to divert energy to ground if the wire is struck. If magnesium were substituted for zinc, the power supply can be eliminated since magnesium is more anodetic that galvanized steel. Copper strapping is preferred over large diameter wire as an inter-connecting media. RF Surge Device Installation Sheet This document provides typical mounting and grounding methods for "GPS+", "SX", "GT", DT, and TSX Families. Non-replaceable elements. DC Block Filters and Arrestors Concrete floors, particularly those at grade level, can provide a conductive path to earth ground during the strike event. Corrosive effects of soil conductivity. Non-replaceable elements. I put 700 watts into mine the first time and it fried. 7$j.`hDJ(zZ@bvq9ZY u1Xfv9WF3{{= `$ gUZ}!<9jvYKD_}@50!SlfCUl^"X5`('3l @-IPRkwLTQKug[03k0/\ gWN<8f9("->Fp|NH!!Qe5_DEzQz.isYIZyFT4 d !cjQn,5LODW^1tK]O/A8G};)''#v@5@^y%H$=\Aw"[]AhE8p}!_ To prevent coupling, the strap should be oriented with the flat side parallel to the tower (the most likely strike point and magnetic field source). LAN and T-carriers require protectors that have wide bandwidths for high frequency data with tightly controlled surge energy specifications. The I/0 protectors can keep the voltage levels between the single point ground and the signal line(s) at survivable limits, but the energy is only diverted elsewhere. It is a good idea to bond (ground) all conductive objects within 1 meter of any single point earthed equipment in the room. Did you know that spark gap protectors with dc continuity will not work on receivers and shunt fed duplexers? This will leave exposed steel that will continue to pit and may even de-alloy. The only alternative is to provide a copper strap path through the house. $155.99 Add to Cart POLYPHASER's VHF50HN 100 - 512 MHz VHF combiner bulkhead protector. Customer must apply PolyPhaser's Weather Proofing Kit (Part Number: WK-1) to seal the unit and cable connections. Your below grade ground system should be made with the same material throughout. One is to totally disconnect the equipment! Easy installation: The PolyPhaser 098-1013G-A is designed to be easy to install and maintain, so you can get your surge protection up and running quickly and easily. i am looking at Polyphaser for an RF surge protector. Without using very expensive specialized test methods, the only way to ensure a low impedance ground system is to follow the suggestions given for conductors, doping and radials. The power line to the transmitter is protected and grounded at the distribution panel where the power line enters the building. Since the IS-50 and IS-B50 are the most widely used PolyPhaser RF protector series, application in Land Mobile Radio, SCADA systems, amateur radio and many others, this paper focuses on their specific testing condition. Mounting screws included with unit. This may be accomplished by installing, on the outside of the building, a panel connected to the ground system with large surface copper strap(s). The buried depth does little when compared to the depth low frequency strike energy penetrates. Other house appliances may be at risk. When a radial is in poorly conductive soil such as buried in a dry, sandy layer, the radial inductance can be calculated as being in air (a very poor conductor). The safety ground can be fixed by adding a distribution panel and protector at the single point ground location or, for small sites, a plug-in protector grounded on the single point ground panel. The panel is designed to mount/ground a PolyPhaser coaxial protector facilitating cable installation. This is the only protector I will put into a naval installation, electric utility SCADA system or public safety system (911 police/fire).