YOKOGAWA wt3000 User Manual

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IM 760301-01E
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App
Index
Power Measurement
Explanation
An efficiency equation can be created by combining the measurement function symbols.
Using the numeric values of the measurement functions, the energy conversion
efficiency of the device can be determined.
• Setting the Equation
Four efficiency equations (h1 to h4) can be defined by assigning the power of an
element, the power of a S function, or the motor output as an operand. To set the sum
of multiple measurement function symbols in the operand of the equation, an equation
consisting of up to 4 terms can be created using Udef1 and Udef2.
Equation Examples
• Efficiency of a Single-Phase, Two-Wire Input/Single-Phase, Two-Wire Output Device
Given
Input: Power of element 1 (P1) and
Output: Power of element 2 (P2)
Efficiency equation: P2/P1
Converter
(Inverter, etc.)
Input power: P1
Output power: P2
• Efficiency of a Single-Phase, Two-Wire Input/Three-Phase, Three-Wire Output
Device
Given
Input: Power of element 1 (P1) and
Output: Σ power of elements 2 and 3 (PΣA)
Efficiency equation: PΣA/P1
• Efficiency of a Three-Phase, Three-Wire Input/Three-Phase, Three-Wire Output Device
Given
Input: Σ power of elements 1 and 2 (PΣA) and
Output: Σ power of elements 3 and 4 (PΣB)
Efficiency equation: PΣB/PΣA
• Efficiency of a Single-Phase, Two-Wire Input Motor
Given
Input: Power of element 1 (P1) and
Output: Motor output (Pm)
Efficiency equation: Pm/P1
• Efficiency of a Three-Phase, Three-Wire Input Motor
Given
Input: Σ power of elements 1 and 2 (PΣA) and
Output: Motor output (Pm)
Efficiency equation: Pm/PΣA
Note
To correctly compute the efficiency, set the power factor of all elements so that all power units
used in the computation are the same. For example, the efficiency over elements or wiring
units with mixed power units of W (watt) and J (joule) cannot be computed correctly.
• Limitations on the Efficiency Computation by Measurement Modes
Efficiency cannot be computed in wide bandwidth harmonic measurement, IEC
harmonics measurement, voltage fluctuation and flicker measurement, and cycle-by-
cycle measurement modes.
5.7 Setting the Equation for Efficiency

YOKOGAWA wt3000 Specifications

General

Brand	YOKOGAWA
Model	wt3000
Category	Measuring Instruments
Language	English