lextec
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How do I ensure Wireless Access Point Lightning Protection according to national standards?
I am installing a small coax antenna onto a thick wood beam about 6 feet from my outdoor access point. It is a hotel and the antenna will be mounted around a mostly concrete building with the antenna coax traversing underneath an outdoor 4ft. wide concrete walkway. This small antenna is out overlooking the pool area. The AP will be attached to wood also, and then powerd via POE where the ethernet cable will run directly into an indoor laundry area down to the first floor, and under the building through a 4 foot crawl space eventually connection to a wireless router, indoors. Should I have lightning protection? And if so how would I accomplish this to meet any national standard. Do I just need lightning arrestors, or do I need to actually run a separate wire along the path of the ethernet cable like a lightening rod? Thank you.
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I suppose it wouldn't hurt but the antenna, the part that sticks up in the air is the first place that lightning will be picked up. This article about lightning rods is about the same things that apply to an antenna: http://en.wikipedia.org/wiki/Lightning_rod
>Should I have lightning protection?
When an ODU is installed on a mast, tower or wall, it may be in one of two possible lightning protection zones: Below the roof, above the roof, and above the roof utilizing a finial
below the room and above the roof with a finial are the recommend installations.
The following protection requirements are mandatory:
• The ODU must be earth grounded
• Shielded CAT 5e cable must be used
• Surge arrestor must be installed at building entry
• There must be an earth connection at building entry
Billy
When an ODU is installed on a mast, tower or wall, it may be in one of two possible lightning protection zones: Below the roof, above the roof, and above the roof utilizing a finial
below the room and above the roof with a finial are the recommend installations.
The following protection requirements are mandatory:
• The ODU must be earth grounded
• Shielded CAT 5e cable must be used
• Surge arrestor must be installed at building entry
• There must be an earth connection at building entry
Billy
ASKER
Does earth grounding the Ethernet surge surpressor at the entry to the building count? Or does this mean I need to run a straight #8 wire directly along the same path as the ethernet wire. There is really no place to plant a deep 6 foot metal rod around this commercial pool. Just running the wire from the antenna is obstructed in almost every place by the walkways to the guests rooms. Was hoping to keep this simple (but within code) Can I ground it into a concrete wall near where I am mounting? The antenna is only 2" clearance from the walkway on the 2nd floor made of concrete. I am more concerned about the code. Guess I am unclear about what earth grounded means. We are a beach resort and only have sand that the buildings are built upon. I have seen wall mounted units in many places and no wires coming from them. Just wondering what their trick is. Thanks as always.
"earth grounded" means different things in different circumstances. "earth grounded" AC outlets means that the third pin is connected correctly to the building electrical ground for safety purposes. For real lighting protection, that ground system is not good enough for a number of reasons. For lightning, you try to route the lightning current away from the building circuits and as directly to a real earth ground as you can.
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Thanks Craig. The Hotel is L shaped around a pool, and the WAP antenna will be mounted directly to the 2nd story FLOOR looking out to the pool and the rest of the property, about 125 x 125 including building. It's all out in the open. The 2nd story floor I reference is the 2nd story walkway so the WAP is mounted to a wood beam that protrudes a few inches from this concrete walkway. If I drill a hole into the concret to a rebar, will this suffice as my ground for the lightning arrestor? And I was wondering what everyone's thoughts were regarding Billy's suggestion of shielded STP cable. Can I get away with using UTP without risking anything since I am using surge protection and lightning arrestors. This is a very basic install with no patch panel. The CAT 5e will come into the office and install to the Router that is plugged into the electrical outlet. Thanks much again.
Connecting to a rebar... I'd say no. If a lightning strip along the outside of the building is available it would be better to use that.
As Billy said, you should use shielded Cat5e for all outdoor installations, but only if the PoE injector and Outdoor-Unit requires it. Technically speaking, if an ODU doesn't require a shielded cable I wouldn't consider it a true ODU. If the AP is located inside you may not need to use STP, but it would be worth checking the manufacturer's specifications for the product. If you do require STP you should use a shielded patch panel.
As Billy said, you should use shielded Cat5e for all outdoor installations, but only if the PoE injector and Outdoor-Unit requires it. Technically speaking, if an ODU doesn't require a shielded cable I wouldn't consider it a true ODU. If the AP is located inside you may not need to use STP, but it would be worth checking the manufacturer's specifications for the product. If you do require STP you should use a shielded patch panel.
ASKER
Ok, I will look for other more suitable grounding. The unit is a Teltronics TT2400 outdoor unit, and I have just looked through the User's Manual and there is only the stipulation of standard Cat 5 wiring. So I guess that means STP won't add anything. Is there an engineering argument for using the STP cable? Also, wouldn't the patch panel be overkill? This is a single cable to a router and I am not sure of the advantage of the additional investment in a patch panel. Thanks.
The spec sheet says nothing about STP. Perhaps you could try sending their support team an email to clarify?
There is nothing that says you definitely have to use STP from an engineering point of view, but if the equipment requires STP you should use it. If shielded Cat5 is used you should always connect to a shielded patch panel, and the panel should be earthed.
Advantages over standard Cat5e are improved resistance to elements, strength, protection from EMI, etc.
There is nothing that says you definitely have to use STP from an engineering point of view, but if the equipment requires STP you should use it. If shielded Cat5 is used you should always connect to a shielded patch panel, and the panel should be earthed.
Advantages over standard Cat5e are improved resistance to elements, strength, protection from EMI, etc.
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Thanks to everyone for their input. I had to split the points for the most useful information. Had hoped for some more context from experts involved with this type of work. But the information provided was indeed useful.
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