Compaq 2000 Series UPS Operation And Reference Manual page 52

If the utility voltage frequently varies outside the UPS operating range
(see Fig 4-6), consider changing from normal to extended range
(+20% to –35%). This provides more tolerance to brief utility voltage
fluctuations.
To update the nominal voltage and operating range parameters:
1. Have a qualified electrician monitor utility voltage.
2. Use the following tables to identify the operating range that most closely
matches requirements:
Operating Ranges (VAC) - T2000 and T2000j Models
Nominal Level
100
110
120
127
Operating Ranges (VAC) - T2000h and T2000h-NA Models
Nominal Level
208
220
230
240
3. For nominal voltage level setting, select configuration parameters
1, 2, 3, or 10 (see Table 4-1).
4. Access parameter 4 to switch from normal to extended range (see
Table 4-1).
Table 4-2
Normal Range
80 to 120
88 to 132
96 to 144
102 to 152
Table 4-3
Normal Range
166 to 250
176 to 264
184 to 276
192 to 288
Configuration 4-9
Extended Range
Not applicable
72 to 132
78 to 144
83 to 155
Extended Range
Not applicable
143 to 264
150 to 276
156 to 288