*
804-257-4738
*Used with permission for WECC purposes

Overview o
Responsible for construction, commissioning and maintenance of relay protection, metering and data acquisition for Transmission - Distribution Substations (800) and
Generation (37) facilities.
o
Dominion has 120 System Protection Technicians positioned in 3 states. Typically a
2 year technical degree, electricity/electronics or instrumentation.
o
50% of our technician work force has < 3 years experience. We have also doubled the number of “contract” electricians working our system (2008-2011).
o
Our Human Performance Program and Training is focused on eliminating the human errors that cause inadvertent outages to the T&D power grid.

Human Errors Tracked By Event Since January 2008
Bumped Pnl Accessed Wrong
Relay/Port
Missed Design
Error
Loss Of Pot Shorted/Rolled
Wires
Loaded /
Jumpered
Wrong Point
Test Blades Control Wiring
(Contractor)

Electric Transmission Work Zone Identification Kit
Designed to Aid in Eliminating Inadvertent Equipment Operations from
Wiring Errors, Jumpering Incorrect Points, Accessing Incorrect Panel/Device, etc.

Our Expectation: Use the Work Zone Identification Kit o
When working on equipment or components that look similar.
o
When working on equipment or components that will be manipulated multiple times.
o
When working on or near trip sensitive or risk important equipment.

Work Zone Identification Kit Insert (front)

Work Zone Identification Kit Insert (back)

Use Work Zone Identification Kit Banners o
To create physical barriers (banners and hangers) to direct the worker to the correct equipment and components and away from high risk equipment.
o
Text on banners used as reminder of our human performance tools and terminology.

Use Work Zone Identification Signage and Flagging o
When working on equipment that is out of service for testing and the equipment requires signage or flagging for operational and/or safety reasons. Alerts others on the job that testing is in progress.
o
Use flagging hangers when working on equipment or components that will be manipulated for operational testing or placed into an abnormal condition during testing period (i.e. scada control switch, breaker control switch, device power on/off switch).
Red- Do Not Operate Green-Equipment Under Test Yellow-Abnormal Condition

o Wire caps will be used to provide an insulated cover up for wires and lugs during transitional periods such as construction jobs.
o Wire caps are color coded: o Red caps for new wiring that is to be terminated in the future.
o Green caps for wiring that is being removed. o Yellow caps for temporary conditions.
o Wire caps are sized to provide a secure fit (sock like) for multiple sized wires and lugs.
Wire Caps Instead of Tape

Terminal Point Barriers o Terminal point barriers used to cover up trip sensitive points on wiring blocks and provides a visual indication of the location of those “trip” points . o Before the task begins, cover any “trip” point that would result in an unwanted event if inadvertently touched or bridged.

P = Positive DC Voltage
Terminal Point Barriers
T = Trip Point
“P” wire
“T” wire
“P” wire
“T” wire
Without Terminal Point Barriers With Terminal Point Barriers

Plastic Sheeting as Barrier o Flame retardant plastic used to build a physical barrier to prevent incidental contact with “live” electrical control components (use when pulling control cable, stripping wire, etc) o The plastic is held in place with nylon blanket clamps.

Events vs. Decline in Experience and Increase In Workload

The Expectation/Requirement o
Technicians and Electricians work together to identify the task risks during pre-job briefing and task preview.
o
Once risks are identified, use the work zone identification kit tools to build appropriate barriers and defenses to prevent unwanted equipment operation.
Contact: Mike.Carden@dom.com
804-257-4738