Electrical Power Distribution

DOE-HDBK-3010-94

Appendix B; Plutonium Recovery Facility

The ventilation system (e.g., ventilation sequencer, differential pressure readouts, damper

positions) is monitored in the control room as well. Unlike process controls, however, the

ventilation system is also operated from the control room via an installed control panel.

Significant parameters and alarms for support buildings, such as the H-8 Liquid Waste

Treatment Facility receipt tank levels, are also provided in the control room. One of two

primary facility announcing system controls is located here as well.

2.1.5.10 E lectrical P ow er D istrib u tion

H Plant is provided with split bus redundant normal power, auxiliary power from the plant

diesel, and safe shutdown power from uninterruptable power supplies (UPS). Normal power

is received from two separate public utilities. Utility A provides power to one main bus via

the 32 substation, while Utility B provides power to the other main bus via the 33 substation.

Automatic transfer switches will connect a given bus to the other substation upon loss of

power from one supplier.

Auxiliary power is provided to the facility by a 850- kw diesel generator located adjacent to

the main building in H-3 B. This small building is constructed in a manner identical to the

main building. Loss of power from both normal sources will automatically start the diesel

and commence a timing sequence that will transfer auxiliary busses to the diesel once it is

running at rated speed. Typical time for power restoration is on the order of 10 seconds.

Upon restoration of power, the ventilation fans will automatically restart in the appropriate

sequence.

There are three separate UPS in H Plant. The first is dedicated to the criticality alarm

system and will provide operational power to the criticality alarm system for up to 3 hours.

The second UPS provides power to the air sampling system and local glovebox control

panels for approximately 1 hour. The final UPS supplies the facility control room for

approximately 0.5 hours.

The building grounding system serves two functions. As the building electrical ground, it

offers a path to ground for electrical faults, providing additional protection along with

breakers and fuse blocks and allowing "bleedoff" of static electrical charges. Its second

function is to provide a "bleedoff" path to ground in the event lightening strikes the building.

2.1.5.11 P rocess an d Instru m en t A ir

Process and instrument air represent two branches of flow from a single source. Filtered air

is drawn into one of two air compressors (on-line and standby units) rated for 300 scfm and

125 psig discharge pressure. The compressor outlet passes through drying towers to one of

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