Communications Systems Grounding Rules | Electrical Contractor Magazine

 

nec article 800

“Article Tips” on page 52 highlights some key points for proper application of Art. How can you keep track of all the details? One trick is to remember these three principles of Art. Keep these communications circuits separate from other circuits, such as those used for power and morrenextpen.tk: Mike Holt. Jul 17,  · Understand NEC Articles and , and how they affect network cabling for electrical engineers. Determine which Article to start from, depending on the circuit type being installed. Identify how the circuits from the two Articles support each other in installation requirements, shared pathways. Article - Communications Circuits. by Mike Holt for EC&M Magazine. Don’t let misunderstandings of Article hang you up. The telephone company provides the cable to a terminal box at the building and installs a ground wire to the grounding electrode system [(B)(4) and ].


The NEC and Communications Circuits | Electrical Construction & Maintenance (EC&M) Magazine


Mike Holt Jan 01, Because Art. The telephone utility typically provides the twisted-pair cable to a terminal board. This board usually is part of an assembly referred to as the network interface device NID. Wiring from that point forward falls within the scope of Art. Cable installation.

The fine print note FPN following Attention to detail is part of good workmanship, and a few strategically placed supports can work wonders — don't shy away from using them. Abandoned cables, nec article 800. You must remove the accessible portion of communications cable that doesn't terminate at equipment and isn't identified for future use with a tag [ This requirement doesn't apply to cables that are installed inside of raceways Art.

The main reason this requirement made it into the NEC is because it nec article 800 the amount of combustible items in a building, and therefore limits the possible spread of fire or products of combustion. Conductor clearances. Overhead communications cables must not be less than 10 feet above swimming and wading pools, diving structures and observation stands, and towers or platforms [ Other overhead conductor requirements are provided in Underground communications wires and cables in a handhole or manhole must be separated from exposed electric light, nec article 800, power, Class 1, and nonpower-limited fire alarm circuit conductors by a suitable barrier [ Where practicable, maintain a separation not less than 6 feet between communications wiring and lightning protection conductors [ A listed primary protector is required for each communications circuit [ Locate it as close as practicable to the point of entrance [ Keeping the shortest practicable distance between the primary protector nec article 800 and the primary protector grounding conductor [ Nec article 800 protectors provide protection against overvoltage and overcurrent conditions that occur due to contact between outside communication conductors and power sources outside of the building.

Thus, they allow for safe direct connection of internal power limited circuits and equipment to conductors that originate outside of the building. Grounding methods. The metallic sheath of communications cable must be grounded or interrupted by an insulating joint as close as practicable to the point of entrance.

Follow the requirements of The grounding conductor must be:. Guarded from physical damage. Where run in a metal raceway, nec article 800, bond each end of the raceway to the grounding conductor. In a structure with a grounding means, the grounding conductor must terminate to the nearest accessible:.

Then bond the grounding conductor to it [ Meeting Don't let the fact that there are eight exceptions and one FPN in The first three exceptions apply to conductors in raceways, boxes, and cables. The next two apply to separation from nonpower-limited fire alarm circuits, and the last applies to support of aerial conductor spans.

The FPN applies to sprinklers in concealed spaces, nec article 800. Five key requirements are:, nec article 800.

If you install communications cables in a Chapter 3 raceway, the raceway must comply with the Chapter 3 wiring method installation requirements [ If you install communications cables in a nonmetallic raceway listed for communications cables, the raceway must comply with Communications nec article 800 and cables installed within buildings must be listed, but the cable voltage rating must not be marked on the cable [ Voltage markings on cables nec article 800 be misinterpreted to suggest that the cables may be suitable for Class 1 or electric light and power applications [ Communications circuits must maintain 2 inches of separation from electric light, power, Class 1, or nonpower-limited fire alarm circuit conductors [ Communications cables must not be supported by a raceway [ They also can't be supported by or attached to the power service mast [ Other requirements for cables within buildings.

Nec article 800 cables can be in the same raceway or enclosure as jacketed cables of any of the following:. Communications conductors must not be run in the same cable with Class 1 conductors. They can be within the same cable with Class 2 or Class 3 conductors, if the cables are installed per Art. Ducts and plenums. Communications cables must not be installed in ducts that transport dust, loose stock, or vapors [ Only where necessary for the direct action upon, or sensing of, nec article 800, the contained air, communications cables can be installed in ducts or plenums if they are installed in electrical metallic tubing, intermediate metal conduit, or rigid metal conduit per Plenum-rated Type CMP cables [ Plenum-rated communications raceways [ Cables installed in vertical runs penetrating more than one floor must be Type CMR [ Floor penetrations requiring Type CMR must contain only cables suitable for riser or plenum use.

Type CM cables must be encased in a metal raceway or located in a fireproof shaft having a firestop at each floor. Plenum- and riser-rated communications cables are not required in one- or two-family dwellings. How can you keep track of all the details? One trick is to remember these three principles of Art.

Keep these communications circuits separate from other circuits, such as those used for power and lighting. Ground the primary protector as close as practicable to the point of entrance, keeping the grounding earthing conductor for the primary protector as straight and as short as possible, nec article 800. If you locate cables above a suspended ceiling, route and support them to allow access via ceiling panel removal, and be sure to identify when to use plenum-rated cables or raceways.

If you install cables in a Chapter 3 raceway, you must conform to the NEC requirements for the raceway system. Be sure to use the right cable type. That may be an external wall or a concrete floor. It might also be rigid metal conduit or intermediate metal conduit that is grounded bonded to an electrode per Normally, you will find the NID at the point of entrance Sidebar on page Wiring from that. Hide comments. More information about text formats. Text format Comments Plain text.

Web page addresses and e-mail addresses turn into links automatically, nec article 800. Lines and nec article 800 break automatically. Leave this field blank. Motor Calculations — Part 1, nec article 800. Conductor Sizing — Part 1 of 2. Load More.

 

Installing communication circuits | Electrical Construction & Maintenance (EC&M) Magazine

 

nec article 800

 

Article - Communications Circuits. by Mike Holt for EC&M Magazine. Don’t let misunderstandings of Article hang you up. The telephone company provides the cable to a terminal box at the building and installs a ground wire to the grounding electrode system [(B)(4) and ]. NEC information; expand your knowledge of the National Electrical Code with our free series of NEC 10 Tips, each covering an aspect of the Code. This article explains Article , Communications Circuits; Part 5 of a multi-part series. Communications systems and circuits in buildings must comply with the applicable rules in National Electrical Code (NEC) Article Even though these systems operate at lower energy levels, improper grounding and bonding can result in severe consequences for equipment, property and .