Specifications
39 Liebert
®
GXT3
™
Using the configuration program, the user may specify the number of GXT3-240VBATT external
battery cabinets attached to the UPS. The factory default is programmed for internal batteries only.
Table 11 shows the estimated run times at different loads.
12.1 Auto-Learning Battery Run Times
As batteries age, the estimated run times 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-
discharge 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.
Internal Battery
+ 4 External
Battery Cabinets
10% 460 360 316
20% 205 191 163
30% 159 138 137
40% 124 108 107
50% 106 97 82
60% 98 81 69
70% 83 71 52
80% 75 61 48
90% 66 51 44
100% 53 48 40
Table 11 Battery run time, minutes, all models
Number of
Batteries/Cabinets
Load Percent
of Capacity
230VAC RT Models
5kVA 6kVA 10kVA