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Grounding Equipment – 3000
Phone: 573-682-5521 Email: hpsliterature@hubbell.com Web: hubbellpowersystems.com
Page 3003
July 2012
1. Clamps
2. Ferrules
4. Support Stud
5. Shrink Tubing
3. Cable
Chance Grounding-Set Tester
• Ideal for performing function
#5 above
• Checks the resistance in a
protective ground set
• Can help locate problems
often remedied by simple
• How-to video is included with
the tester
• See Catalog Section 2450, “Instruments and Meters,”
for details and ordering information
Safety Reviews
• Temporary grounding practices should be reviewed on
a regular basis
• As part of a total maintenance program, routine
reviews should be scheduled apart from sessions to set
new practices for system upgrades and additions
• These basics should be included on a review checklist:
1. Clamp designs specific to each application,
2. Cable sized for fault-current potential (see table on
page 3002) and minimum-slack lengths
3. How construction affects placement of grounds
4. Work procedures outlined above
5. Inspect and test each grounding set
Selecting grounding clamps and cable
The Chance grounding line comprises both ready-made sets and separate components for your specific needs.
Among the options and criteria to consider:
• Functional fit—Sizes of the clamp types in this section
appear in ascending order of maximum-main-line size.
By design, many clamps serve a wide size range for
their conductor type (cable, bus or tower)
• Adequate capacity—Published ratings for both clamps
and cable must withstand maximum-potential system
fault-current magnitude and full-time duration.
Certified test reports are available on request
• Coordinated connectors—Terminal (either pressure-
type or threaded-type) selected for clamps dictates the
cable ferrule type (either plain or threaded) to match
• On-site handling—Application clearances and fit (for
overhead conductors and ground wires, transmission
tower shapes, URD apparatus or substation buswork)
affect clamp and cable dimensions
Installation information
• Several training aids available on request
• Chance videos and technical manuals provide details on proper installation
• Consult your Chance representative for any additional assistance
How to order a Grounding Set
In addition to the specifying criteria above, each part of a grounding set requires certain choices:
1. Clamps
• ASTM designations for Type, Class and Grade given
for clamps shown in this section
2. Ferrules
• Copper or aluminum
• Plain or threaded
3. Cable
• Length required to reach application distances
• ASTM Type I with black or yellow elastomer jackets
for temperatures from -40°F (-40°C) through +194°F
• ASTM Type III with clear thermoplastic jacket for
temperatures from +14°F (-10°C) through +140°F
(+60°) should be used only in well-ventilated areas
4. Support Stud
• This option recommended on only one clamp to help
control lifting the set to the first clamp attachment
5. Shrink Tubing
• This translucent option recommended for stress
relief and inspection of cable strands between
ferrule and jacket.