IEEE 937-2019 pdf free download

IEEE 937-2019 pdf free download.IEEE Recommended Practice for Installation and Maintenance of Lead-Acid Batteries for Photovoltaic (PV) Systems.
5.2.4 Environmental considerations
The following environmental aspects should be considered during the design or selection of the battery enclosure:
a) The enclosure shall be ventilated, either by natural or induced means, to prevent the accumulation of an explosive hydrogen mixture, and to limit the accumulation of other haiardous gases. The hydrogen concentration shall be limited to less than 2% by volume. The enclosure design should either avoid creation of difficult-to-ventilate areas, including false ceilings, or make adequate provision for their ventilation. The amount of hydrogen released is typically very small under most conditions, and no extra mechanical ventilation is usually necessary if the battery enclosure is not completely “sealed.” See IEEE SW 1635TM [85] for further information and expected hydrogen gas release.
b) To prevent battery damage. the enclosure should be designed to maintain the electrolyte temperature above its freezing point. The temperature at which the electrolyte will freeze for a given battery state of charge and operating-specific gravity may be obtained from the battery manufacturer. Extremely high electrolyte temperatures may cause excessive water usage and may damage the battery. Battery manufacturers may recommend a maximum operating temperature for their batteries.
c) A cell electrolyte temperature of 25 0(1 is nonnally the basis for rated performance in North America. A location where this temperature can be maintained at or below this level should contribute to optimum battery life. Either passive or active means to reduce temperature excursions from 25 C should be considered. Passive means can include partial burial of enclosures, color of exterior finish. and insulation. Active means can include forced-air ventilation.
NOTE- If the electrolyte temperature varies from optimum. sizing may be atTectxl.
d) Temperature differences between cells within the battery should be limited to 3 C, Localited heat sources, including direct sunlight, radiators, steam pipes. and space heaters should be avoided.
c) Illumination of enclosures during time of maintenance should be adequate for the safety and effectiveness of personnel.IEEE 937-2019 pdf free download.