7-5
IM WT1801-01EN
Notes about the Numeric Data Display
• “-------” is displayed if a measurement function is not selected or if there is no numeric data.
• If Urms, Umn, Udc, Urmn, Uac, Irms, Imn, Idc, Irmn, or Iac exceeds 140% of the measurement range, “-OL-”
is displayed to indicate an overload value.
• If the voltage or current exceeds 140% of the measurement range, “-OL-” is displayed to indicate an overload
value for P.
• If the measured or computed result cannot be displayed using the specified decimal place or unit, “-OF-” (for
overflow) is displayed.
• When the measured voltage or current value is at or below the percentage of the measurement range
indicated below, the values of Urms, Umn, Urmn, Irms, Imn, Irmn, and other measurement functions that are
based on them are displayed as zero. The λ and Φ functions will return errors (“Error” is displayed).
• When the Crest Factor Is Set to CF3
When Urms, Uac, Irms, or Iac is 0.5% or less When Umn, Urmn, Imn, or Irmn is 2% or less
• When the Crest Factor Is Set to CF6
When Urms, Uac, Irms, or Iac is 1.0% or less When Umn, Urmn, Imn, or Irmn is 4% or less
• If the analysis window width (number of cycles of the fundamental signal) that is determined by the
fundamental frequency is shorter than the data update interval, harmonic data is not measured, and “-------” (no
data) is displayed. If this happens, increase the data update interval. For example, if the data update interval
is 50 ms and the fundamental frequency is 10 Hz (the period is 100 ms), the analysis window will be 1 wave
wide (see section 6.6 in the getting started guide, IM WT1801-03EN), and the data measurement interval will
be 100 ms. In this case, the time required for harmonic measurement is approximately 150 ms or greater (data
measurement in data processing time). To measure and display harmonic data, set the data update
interval to a value greater than or equal to 200 ms.
• There is no overload value indication (“-OL-”) or zero indication (suppression to zero) for the numeric data of
harmonic orders 0 (DC) to 500.
• If the measured frequency is outside the measurement range, the fU or fI function returns an error (“Error” is
displayed).
• If the power factor λ is greater than 1 and less than or equal to 2, λ returns 1. Φ returns zero.
• If λ is greater than 2, λ and Φ return errors (“Error” is displayed).
4-, 8-, and 16-Value Displays (4 Items/8 Items/16Items)
Item Number to Set (Item No.)
Select the number of the item that you want to configure.
Function (Function)
You can select any of the measurement function types listed under “Items That This Instrument Can Measure.”
If you select None, no measurement function is displayed for the selected item.
Direct Function Selection (U/I/P, S/
Q/λ/Φ,
WP/q/TIME, FU/
FI/η, and
U/I MODE)
When the menu is not displayed, you can change which of the selected measurement functions is displayed
using the function select keys (U/I/P, S/Q/λ/Φ, WP/q/TIME, FU/FI/η, and U/I MODE).
U/I/P, S/Q/λ/Φ, WP/q/TIME, and FU/FI/η
Each time you press U/I/P, the selected function switches in order between U, I, and P. The same is true for S/Q/
λ/Φ, WP/q/TIME, and FU/FI/η.
U/I MODE
Each time you press the key, measurement function U or I switches in order between rms, mean, dc, rmean, and
ac.
7 Numeric Data Display
