Alpha Technologies FXM350_Micro350 UPS - Manual (Page 94)

017-241-B0 Rev B 92
8.2 Testing and Replacing the Batteries
8.2.1 Battery Life
Batteries lose their ability to store power as they age. Regularly test the batteries to ensure that they can con-
tinue providing reliable service. Battery life is reduced by three major factors:
• Temperature – higher ambient temperatures, especially above 25°C (77°F), will reduce battery life. For
example, an average operating temperature of 27°C (81°F) will likely reduce the life of the battery by
25%. Ensure that the Alpha FXM and batteries are situated in a well ventilated area with adequate tem-
perature control. A cool environment is preferable.
• Number of discharge cycles – the more frequent the batteries are discharged, the shorter the battery
life. Frequent power outages imply the need for more frequent battery replacement.
• Depth of discharge – the longer the batteries are required to provide back up power, the shorter the bat-
tery life. Frequent full discharging and the associated recharging of the batteries reduces the life. Shut
down the electrical load or return to primary power as soon as possible to extend the battery life.
8.2.2 Battery Run Time
The chart below shows typical run times (time to full discharge) for the standard batteries supplied with this
unit. These runtimes are for batteries in new and good condition. The run time performance will deteriorate
over time in a progressively decreasing curve.
Battery V
oltage (V)
Discharge Time
Discharge Rate Characteristics
100%
Load
50%
Load
Figure 70 — Typical Discharge Characteristics for Lead Acid Batteries