Eaton Power Xpert PXM 4000, Руководство пользователя и инструкция по установке

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6 Functions on the Web Server Pages
ENERGY
The Power Xpert Meter measures and accumulates three kinds of energy values every 200 mil-
liseconds, Real Power (Watts), Reactive Power (vars) and Apparent Power (VA). With four different
types of accumulation; forward, reverse, net and sum for Real Power and Reactive Power. These
measurements are configured to calculation the kWh Forward/Reverse, Net and Sum; kvarh Lag/
Lead, Net and Sum and kVAh.
Real Power (Watts). Note: Watts calculated is only valid for AN, BN, and CN selections.
Reactive Power (var) You can select the means of calculating vars is in the QuickSetup page. By
default, reactive power is calculated from VA and Watts as sqrt(VA^2 - W^2). As a result, harmonic
power is included with vars.
Optionally, reactive power is calculated via a 90-degree phase shift of the fundamental. As a result,
harmonic power is typically excluded from the vars. and is the product of the voltage, the current,
and the sine of the phase angle between them.
Apparent Power (VA) is the square root of the sum of the squares of the active and reactive pow-
ers.
Separate energy registers accumulate energy values over a period of one calendar month. At the
end of every calendar month, energy values along with peak demand values with date and time
stamps are saved as last months values. At this point energy accumulators are reset and begin ac-
cumulating values for next month.
TIME OF USE
The meter supports four rate periods for Time Of Use (TOU): A, B, C and D in addition to total rate,
which is independent of time of use. Energy values are accumulated separately for each of these
rate periods. The Time of Use page also display the Present, Peak, and Peak Today (the peak
value for this day) Demand.
DEMAND PROFILE
Demand Profile is the magnitude and duration of loads applied in a prescribed time sequence,
including the transient and steady-state characteristics of the individual loads. The Power Xpert Me-
ter logs demand profile data from the following sources:
• kWh/kw: Forward, Reverse, Net, Sum,
• kVAh/kVA - kVARh/kVAR: Received,Delivered, Net, Sum, and Total Current in Amperes.