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8.0 Compaq Recommended Specifications Operating Environment
The specifications presented are recommended by Compaq / Digital to optimize the
operating environment for your computer hardware.
8.1 Voltage
Nominal:
Single-phase products:
120 Volts
Three-phase products:
208Y/120 Volts
Range:
Single-phase products:
104 - 128 Volts
Three-phase products:
180 - 220 Volts
Crest Factor:
1.4 + 1%
8.2 Voltage Unbalance
Equipment requiring 3-phase power shall operate satisfactorily when the voltage unbalance is 5% or less as
calculated below.
(Vmax - Vmin) x 100
Unbalance percent = ------------------------------
(Vavg)
Where;
Vmax = maximum line-to-line RMS voltage
Vmin = minimum line-to-line RMS voltage
(VAB + VBC + VCA)
Vavg = ----------------------------
3
VAB, VBC, VCA = line-to-line voltage
8.3 Voltage Transients
Power line transients should be no greater in amplitude than the value of the nominal AC RMS voltage. This
limitation applies to common and transverse mode transients of positive or negative polarity as they are imposed in
the AC sine wave.
8.4 Voltage Harmonic Distortion
The power source voltage total harmonic distortion should not exceed 5% with any single harmonic not exceeding
3% of the fundamental frequency.
8.5 Frequency
Nominal:
60 Hz
Range:
59 - 61 Hz
8.6 Phase Angle Unbalance
Maximum of 5o variation from the 120o relationship for 3-phase power.
8.7 Phase Rotation
ABC
