1. Equipotential Grounding Procedures Protective Grounding Training

2. Purpose of Grounding Electrostatic Induction Electromagnetic Induction
De-energizing and grounding electrical lines/equipment represents
the best possible protection for high-voltage line workers. If
it isn’t grounded, it isn’t dead! Some of the dangers you face:
Electrostatic Induction
Electromagnetic Induction
Accidental Closing
Accidental Contact
Equipment Failure
Backfeed

3. Requirements of a Protective Ground
For proper protection, protective grounds must fulfill the following requirements:
Low Resistance
Inspection and Testing
Connection at Proper Points
Provide for a Minimum Potential Difference
Across the Worker
Movement of Protective Grounding Cables

4. Applying Grounds Properly
All grounding clamps should be placed on primary
conductors using an approved ‘hot stick’
Use only approved grounding cables and clamps
The conductor must be tested for ‘dead’ with an
approved and properly functioning tester
If voltage is detected, stop work immediately
until the line/equipment is de-energized and retested
Clean the attachment surfaces before connecting
grounding clamps
When grounding de-energized equipment, connect
cable to ‘ground’ before approaching a conductor
that is to be grounded
Continued

5. Applying Grounds Properly, Con’t
No grounding connection should be placed such as to
interfere with work to be done. Stow cables carefully.
Do not coil cables
Workers should avoid standing near earth grounded
points because of danger due to ‘step-touch’ potential
Avoid installing protective grounds in series with a fuse
or switch. A Supervisor should approve this procedure
if it is found to be necessary
Grounding cables used should be sized to carry the
anticipated fault current

6. Grounding Overhead Lines
On Metal Structures:
The structure itself must be grounded and all
protective grounds should be connected to the structure
On Wooden Structures:
All protective grounds should be attached to a grounding
‘cluster’ immediately below the feet of the workers. This
grounding cluster should be anchored deeply into the
wooden pole to ensure an adequate path to ground

7. Grounding Underground Circuits
Underground circuits represent an additional hazard to the worker.
Additional precautions are required and only workers qualified to work
on underground systems should perform such work.
All conductors of the circuit to be worked on should be
opened and grounded at the closest opening points
Before grounding the circuit, test the conductors using the
same precautions as with O/H lines
Before cutting into an assumed ‘dead’ underground primary
cable, pierce the cable from a remote location to test for
‘dead’ once again (spiking clamp w/ hot stick or remotely
actuated hydraulic cutting tool are typical methods)
Follow Company practices concerning protective insulation
and grounding of URD systems (contact Safety Manager for questions)

8. Typical Example Wooden Pole Equipotential Grounding Scheme Key
Description
1. Ground Clamp
2. Two Ferrules Applied
3. Cluster Bar
4. Screw Ground Rod
5. #2 Clear Jacket Cable
6. Parking Stand
Optional

9. Protective Grounding Training
Copyright by the Institute for Safety in Powerline Construction
5501-A John Eskew Blvd.
Alexandria, LA
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may not be reproduced in any form without
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Institute for Safety in Powerline Construction