Section 5 - PROTECTION, GROUNDING AND BONDING
5.1 LIGHTNING PROTECTION
- 5.1.1 GENERAL
Lightning protection of
telecommunications facilities is essential. While federal and
state standards must be adhered to, local conditions may require
additional investigation and/or modifications to meet site,
equipment, environmental or safety requirements.
Articles 250 "Grounding" and 800 "Communications Circuits" cover
general requirements for grounding, bonding and protecting
electrical and communications circuits. NFPA 78 "Lightning
Protection" addresses zone protection and other items which are
All cabling (including grounding to
building ground) within the building and entrance facilities shall
be installed with protection from lightning and power surges via
grounding and bonding.
- 5.1.2 MATERIALS
The three most frequently
used lightning protectors are listed below. Consult
Telecommunications Center for a determination of the most
appropriate protection for the condition.
Use AT&T, part number 3B1E-W gas
- AT&T Protector -- AT&T, part number 189B1-25 for 25
- AT&T Protector -- AT&T, part number 189B1-50 for 50
- AT&T Protector -- AT&T, part number 189B1-100 for
Homaco part number 50M-201-____19
rack mounting shall be provided. (ITCS will specify part number
suffix required for the particular application.)
Protection Block -- part number R66P25QCVS. The gas protection
module shall be AT&T, part number 3B1E-W.
AT&T, part number 110ANA1-06 for single drops of 6-pair or
less. Use AT&T, part number 3B1E-W gas protector modules.
- 5.2.1 GENERAL
All MC grounding shall use a
single point scheme from the building main transformer. EIA/TIA
607 requirements must be followed.
All shields shall be
bonded to a common ground.
All riser cable must be
shielded and properly grounded to the building ground through
grounding facilities provided at the MC (Main Cross-connect Room).
All protector blocks shall be connected to the
backboard ground busbar using NEC code 6 AWG copper wire.
- 5.3.1 GENERAL
Bonding is to be durable,
strong and of low impedance to assure electrical continuity.
EIA/TIA 607 requirements must be followed.
terminating to cable trays and wireways shall be mechanically
fastened to the tray clamps or equivalent. The cable tray or wire
way shall be grounded to the main building grounding system with a
wire not smaller than #6 AWG copper.
A resistance of
.001 ohm or less indicates a high-quality junction and is required
per the Building Industry Consulting Services International
(BICSI) Telecommunications Distribution Methods Manual.