Independent Design Review

DOE-HDBK-6004-99

Independent Design Review

The primary objective in the independent design review of the Emergency/Back-up power system is

to determine that these systems satisfy the acceptance criteria and will perform their design functions

during fusion facility normal operation, anticipated operational occurrences, and accident conditions.

In the independent design review, the descriptive information, including the design bases and their

relation to the acceptance criteria, preliminary analyses, electrical single line diagrams, functional logic

diagrams, preliminary functional piping and instrumentation diagrams (P&ID), and preliminary

physical arrangement drawings are scrutinized to determine that there is reasonable assurance that

the final design will meet the these objectives.

Electrical Power Systems

Combustion turbine-generators

Recently, the combustion turbine-generator has been used as an emergency power source in the

power plants and the other heavy industries due to it's high reliability, availability, and maintainability.

Therefore, design should perform an application study for the use of combustion turbine as an

emergency power source in the fusion facility. (see ASME 91 and West 211)

Grounding

A facility grounding grid consisting of bare copper cables buried beneath grade will be furnished to

limit step and touch potentials to safe values under all fault conditions. Bare copper risers should be

furnished for all electrical underground ducts and equipment, and for connections to the grounding

systems within buildings. The design analysis will be based on the procedures and recommendations

of IEEE-80.

Grounding within buildings should be in accordance with the NFPA 70. Grounding systems

connected to the station ground grid should be provided in each building with connections made to

metallic tanks, equipment, cable trays, and exposed metal structures. Every other perimeter steel

column should be connected directly to the ground grid. Each major piece of equipment or tanks

should have two ground connections diagonally to each other.

System and Equipment Grounding

System and equipment grounding should be in accordance with IEEE-142.

One No. 4/0 AWG bare copper cable should be installed with each underground electrical duct run.

It should be connected with the ground cables from other duct runs at each manhole. All hardware

in each manhole should be bonded to these ground cables.

All metallic structures, towers, poles, and like items should be connected to the ground grid.

All switchgear, motor control centers, and control cabinets should be furnished with horizontal

ground bus. The ground bus in switchgear and MCC's should be connected to the grounding system

with one No. 4/0 AWG copper ground cable at each end tied to the building steel or a ground pad

set in the floor. The ground bus in control cabinets should be connected to the grounding system