A
LIGHTNING PROTECTION AND GROUNDING
Page T-3
Repair and Service Manual
Read all of Section B and this section before attempting any procedure. Pay particular attention to all Notices, Cautions, Dangers and Warnings.
GS-726-006
EFFECTIVE:
10/19/92
REVISION:
SUPERCEDES:
Rev -, ECN 027194
TITLE :
General Specification: Lightning Protection and Grounding
trating or structurally damaging the building. This is done by providing a low impedance path from the air terminals to the
earth electrode system.
10. Equipment Fault and Personal Safety System
The equipment fault protective system ensures that personnel are protected from shock hazard and equipment is pro-
tected from damage or destruction resulting from faults (lightning induced surges) that may develop in the electrical sys-
tem. Deliberately engineered ground conductors (green wire safety ground) shall be provided throughout the AC
distribution system to afford electrical paths of sufficient capacity, so that protective devices can operate promptly and
efficiently. The use of conduit for grounding in lieu of a dedicated green wire is unacceptable.
Install the green wire ground (#6 stranded) with the AC power distribution conductors. There shall be no green wires
spliced within the conduit. All splices shall be performed at the appropriate junction boxes.
Bond the ground conductor to all pull boxes, junction boxes and power panels.
In existing facilities where an existing conduit is not large enough to accommodate an additional ground conductor, or
where a conduit section is insulated from other conduit sections, an external ground conductor may be installed to main-
tain continuity. All mounting hardware and connectors shall be UL approved.
All DC chargers are to be grounded to the green wire ground using UL approved connectors. At no point should the
chargers be isolated from the grounding system.
All interior grounding should return to a single ground point. From this location it is then connected to the exterior ground
system. Optional Interior Ground Halo: If an interior ground halo is to be installed around the inside perimeter of the struc-
ture, this conductor (#2/0 green insulated minimum) shall be securely fastened to the structure.
All connections to the halo shall be made using UL listed connectors.
Transient Voltage Surge Suppression: TVSS shall be provided at the main electrical service entrance panel. Protection at
this point shall be as follows:
UL 1449 Listed device
25,000 ampere surge capacity with maximum 495 volt clamping voltage
Protection should be Line to Ground, Neutral to Ground and Line to Neutral
Internally fused for safety
Failure mode indicator lights
Suppression may be as the 14000 series of Harger Lightning Protection, Inc., 1066 Campus Drive, Mundelein, IL (800-
842-7437), or MBP 120EFI series from EFI Electronics Corporation, 2415 South 2300 West, Salt Lake City, UT (801-977-
9009).
