In case the UPS does not contain internal batteries and/or the customer needs more backup time, Hyundai offers various external battery packs that match UPS properly. There is a test button on the battery cases that can be used to check the fuses and battery voltage status.These units are designed to be installed in vertical or horizontal position, all in a parallel configuration.
When battery packs are added, special caution should be taken to adjust the charging current of the UPS. Typically, to obtain the maximum life and performance, the charge current of UPS should not be more than 0.25 or less than 0.08 of total connected batteries nominal capacity in Ah. These battery packs are specifically designed for sealed lead acid batteries, thus their best performance is obtained at 15 to 25 °C.