Filter
Top Products
Specifications
36
Using the configuration program, the user may specify the number of Liebert
®
external battery
cabinets attached to the UPS. The factory default is programmed for internal batteries only.
See Table 11 shows the estimated run times at different loads.
12.1 Auto-Learning Battery Run Times
As batteries age, the estimated runtimes may become less accurate. The Liebert GXT3
™
is
programmed to “learn” from a full battery discharge and modify the estimated runtime for the
measured battery capacity. This can improve accuracy and compensate for aging batteries or
batteries that operate at different ambient temperatures.
The UPS will update the anticipated run time calculation only under certain conditions.
• The UPS must have a steady load that is greater than 20%.
• The UPS must be at 100% charge at the start of a battery discharge.
• The battery discharge must continue uninterrupted until the batteries reach their end-of-dis-
charge voltage.
If all conditions are not met, the run time calculation will not be modified.
If the configuration program is used to change the number of battery cabinets, then the values in the
battery above table will be restored. This will override any value that is Auto-Learned.
Table 11 Typical battery run times, minutes at 25°C (77°F ), 100% resistive load
Number of
Batteries/ Cabinets
Load%
10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Internal Battery 1055240272117141210 9
Internal Battery
+ 1 External
Battery Cabinet
187 106 78 53 47 40 34 28 23 21
Internal Battery
+ 2 External
Battery Cabinets
217 146 106 91 71 53 49 45 41 37
Internal Battery
+ 3 External
Battery Cabinets
360 188 132 106 95 79 68 53 50 47
Internal Battery
+ 4 External
Battery Cabinets
360 205 159 124 106 98 83 75 66 53