42 practical guide to electrical grounding – ERICO Practical Guide to Electrical Grounding User Manual
Page 50
42
Practical Guide to Electrical Grounding
Fig. 2-48
Very large buildings require more air terminals,
down leads and ground terminals.
Fig. 2-47
More extensive systems are required on larger
buildings and with different soil conditions.
Fig. 2-49
Protected areas can also be determined using the
rolling ball theory.
No Air Terminal; Roof Edge
Covered Under Higher
Air Terminal Protection.
150 Foot
Radius
CADWELD Type VB
Copper
Downlead
Weld
Lightning
Mast (Pipe)
CADWELD Type VV
Copper Downlead
Main Grid
CADWELD Type TA
Fig. 2-51
Steel tower lightning masts may be used in
locations such as electrical substations.
Fig. 2-50
All rooftop equipment must have air terminals unless
they have skins more than 3/16 inch thick. If they
have skins more than 3/16 inch, they must be proper-
ly bonded and will be considered as air terminals.
24" Min.
Grounding Book 4/14/99 10/5/99 6:01 PM Page 42 (Black plate)
- 6Z34VF14 Rod Hanging Basket Tray Clip (1 page)
- 766PM Far Side Box Support (1 page)
- 766PMD Far Side Box Support (1 page)
- CADDY MPVTI Low Voltage Mounting Clip (2 pages)
- H-Series CADDY PYRAMID Support System (3 pages)
- CADDY PYRAMID RL, PIPE RETAINERS (2 pages)
- CADDY PYRAMID Rooftop Equipment Support (4 pages)
- CADDY PYRAMID Single Post Support (1 page)
- CADDY PYRAMID TF Series, Fixed Height Tool-Free Supports (2 pages)
- CADDY ROD LOCK Anchor Screw (2 pages)
- CADDY ROD LOCK Beam Clamp (2 pages)
- CADDY ROD LOCK Channel Nut (2 pages)
- CADDY ROD LOCK L-Bracket (2 pages)
- CADDY ROD LOCK Strut (2 pages)
- CADDY SPEED LINK Riveted Accessories (4 pages)
- CADDY SPEED LINK SLK-Keyless Locking Device and Bulk Cable (2 pages)
- CADDY SPEED LINK SLK-Keyless Locking Devices (2 pages)
- CADDY SPEED LINK-Accessory Cables (1 page)
- CADDY SPEED LINK-SLK Cable End Accessories (4 pages)
- TSGB Series Screw Gun Bracket (2 pages)
- GLIDER Electrical Box Attachment (2 pages)
- H Series-Electrical Box Bracket (2 pages)
- ROD LOCK Plywood Pre-set Anchor (2 pages)
- ROD LOCK Strut End Bracket (2 pages)
- ROD LOCK Strut (2 pages)
- CADDY ROD LOCK Strut Nut (2 pages)
- CER4 Cable from Stud (2 pages)
- High Performance CADDY CAT HP J-Hook Assemblies (6 pages)
- KBT Wire Basket Tray Clip (1 page)
- MPCB1220 (2 pages)
- SBC Series, Beam Clamp, 3/8" and M10 (1 page)
- TSR200 Telescoping Strut Replacement Bracket (2 pages)
- TSRBS1625 Telescoping Box (3 pages)
- Universal Pedestal Clamp (2 pages)
- Branch Line Restraint Device (2 pages)
- Branch Line Restraint Strucural Attachment Fitting for Steel 12 gauge (2 pages)
- Branch Line Restraint, Structural Attachment Fitting for Concrete or Wood (2 pages)
- Branch Line Restraint, Structural Attachment Fitting with 3/8"-16 male thread" (2 pages)
- 510 CADDY EZ RISER (2 pages)
- 429 CADDY MACROFIX PLUS NI (1 page)
- Seismic Hanger Clamps (3 pages)
- CADDY PYRAMID Equipment Supports (3 pages)
- CADDY ROD LOCK Bottom-Mount Duct Bracket (2 pages)
- Bottom-Mount Duct Bracket, Narrow (2 pages)
- Top-Mount Duct Bracket (2 pages)