Telephone system central offices contain large battery systems to provide power for customer telephones, telephone switches, and related apparatus. Terrestrial microwave links, cellular telephone sites, fibre optic apparatus and satellite communications facilities also have standby battery systems, which may be large enough to occupy a separate room in the building. In normal operation power from the local commercial utility operates telecommunication equipment, and b.
Charging in Series: Lead-acid batteries are strings of 2 volt cells connected in series, commonly 2, 3,4 or 6 cells per battery. Strings of Power-Sonic batteries up to 48 volts and higher may be charged in series safely and effi-ciently.
Vented lead acid batteries shall be located in rooms with outside air exchange, or in well-ventilated rooms, arranged in a way that prevents the escape of fumes, gases, or electrolyte spray into other areas. Ventilation shall be provided to ensure diffusion of the gases from the battery, to prevent the accumulation of an explosive mixture.
Do vented lead acid batteries need a separate battery room?
Vented lead acid batteries installed in medium voltage main substation buildings and unit substations, electrical equipment rooms and control system rack rooms shall not require a separate, dedicated battery room and shall be in accordance with SES E14-S02. The battery room and installation shall comply with IEEE 484, NFPA 70 and OSHA 29 CFR.
Batteries often used in battery rooms are the flooded lead-acid battery, the valve regulated lead-acid battery or the nickel–cadmium battery. Batteries are installed in groups. Several batteries are wired together in a series circuit forming a group providing DC electric power at 12, 24, 48 or 60 volts (or higher).
What is a lead-acid battery?
Lead-acid battery is a type of secondary battery which uses a positive electrode of brown lead oxide (sometimes called lead peroxide), a negative electrode of metallic lead and an electrolyte of sulfuric acid (in either liquid or gel form). The overall cell reaction of a typical lead-acid cell is:
It is common knowledge that lead-acid batteries release hydrogen gas that can be potentially explosive. The battery rooms must be adequately ventilated to prohibit the build-up of hydrogen gas. During normal operations, off gassing of the batteries is relatively small.