Current Unbalance; Magnetic Fields; Electric Fields - Compaq ALPHA GS320 Information Manual

8.8 Current Unbalance

Equipment requiring 3-phase power shall operate satisfactorily when the current unbalance is a maximum of 5
amps or 20% as calculated below.
(I max - I min ) x 100
Unbalance percent = --------------------------
Where;

8.9 Magnetic Fields

Most equipment, excluding monitors and some disk and tape products at power line frequencies, can operate
properly up to the AC magnetic field flux density limits specified below. Above these limits, the operation of some
equipment may be impaired.
Frequency (Hertz)
50
500
1000
10000
500000
For high resolution monitors using refresh rates different from the power line frequency, the maximum AC magnetic
field flux density at power line frequencies is 7.07 mGauss RMS (20 mGauss peak-to-peak). For low resolution
monitors, the maximum AC magnetic field flux density at power line frequencies varies with the product, but is
always greater than 7.07 mGauss RMS. The maximum DC magnetic field flux density limit up to which most
monitors operate properly is approximately 2.0 Gauss.
For some disk and tape drive products, the maximum Dc and AC magnetic field flux density specified at power line
frequencies is 3.0 Gauss. Other disk and tape drive products can withstand higher magnetic field flux densities
Avoid storage of media in Ac or DC magnetic fields. In unavoidable locations, the media should only be subjected
to AC magnetic field flux densities up to a maximum of 3.0 Gauss.

8.10 Electric Fields

Maximum of 2 volts/meter cumulative total for radiated fields from 10 kHz to 1 GHz.
Ensure that not more than 1 volt RMS is present on the AC connection points to the computer system from 10 kHz
to 30 MHz. Measure between frame of the equipment and all phase, neutral, and grounding connections at the
power receptacle(s).
(I avg )
I max = maximum line currents in RMS amperes
I min = minimum line currents in RMS amperes
(I A + I B + I C )
I avg = --------------------
3
I A , I B , I C = line currents in RMS amperes
Maximum field (Gauss)
10.0
2.0
1.0
0.1
0.002
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