Location

DOE-HDBK-1092-98

NEC Sections 2506; 305-6

Figure 6-3. The ungrounded frame of a generator is acceptable as a grounding electrode if the circuit

conductors are insulated from the frame and all other grounded surfaces.

6.5.2 LOCATION

Storage batteries should be located in a protective enclosure or area accessible only to qualified

persons. A protective enclosure can be a battery room; a control building; or a case, cage, or fence

that shall protect the contained equipment and minimize the possibility of inadvertent contact with

energized parts.

6.5.3 VENTILATION

The battery storage area shall be ventilated by either a natural or powered ventilation system to

prevent accumulation of hydrogen. The ventilation system shall limit hydrogen accumulation to less

than an explosive level. See NESC, Rules 14, and 120G, for inspection information and rules

concerning gel-type and lead-acid batteries.

6.5.4 CONDUIT

Because the vapors given off by a storage battery are very corrosive, the wiring shall withstand the

corrosive action, and special precautions are necessary as to the type of insulation used and the

protection of all metalwork. It is stated by their respective manufacturers that conduit made of

aluminum or silicon-bronze is well suited to withstand the corrosive effects of the vapors in battery

rooms. In contrast, if steel conduit is used, it is recommended that it be zinc-coated and kept well

painted with asphaltum paint.

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