The main objective of a battery system is to provide standby and emergency power to operate industrial, consumer, commercial or protective devices. Some of these devices include emergency lighting units, uninterruptible power supplies, continuous process systems, operating controls, switchgear components and protective relays.
In emergency situations, it is essential that these devices be in proper operating condition. Failure of a DC system or the battery can result in operational failure of the devices connected to that system. System failure can lead to loss of revenue, damage to equipment, and/or injured personnel.
It is a common situation for a floating DC system to develop grounds within it. When a battery system is partially or completely grounded, a short circuit is formed across the battery and consequently may cause the protective device to fail to operate when needed.