Worked example
No result for these values. The message above the form says which field to change.
Current THD
%
- Root-sum-square of the entered harmonics
- A
- Fundamental-plus-harmonics RMS
- A
- Largest entered harmonic order
- 5
- Largest entered harmonic magnitude
- 12 A
- Included harmonic orders
- 5, 7, 11
Current THD from the harmonic orders entered. No IEEE 519 limit is applied, and this does not show compliance at the point of common coupling.
Underlined figures are rounded. Select one to copy its full value.
Method and assumptions
Formula
THD = 100 × √ΣXh² ÷ X1; current TDD = 100 × √ΣIh² ÷ ILEnter RMS magnitudes for integer harmonic orders 2 through 50. THD uses the fundamental as denominator; current TDD uses maximum demand load current at the point of common coupling.
Limits of this result
- Every entered magnitude must be RMS, use the same unit and represent the same measurement window and point.
- Interharmonics, subharmonics, phase angles, aggregation rules, instrument bandwidth, windowing and measurement uncertainty are outside this arithmetic.
- IEEE 519 voltage and current limits apply at the relevant point of common coupling and require system context; this tool does not classify compliance.
- For current TDD, maximum demand load current IL is not the instantaneous fundamental current and must be established by the applicable measurement method.
Technical sources
Put the value to work
Read the related engineering guidance, or carry this task into System Builder to identify the signal path and EpiSensor products.