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IM WT1801-01EN
Independent Input Element Configuration (Element Independent)
In the wiring system settings, you can select whether to set the measurement range or sync source of input
elements in the same wiring unit collectively or independently.
Turning Independent Input Element Configuration On or Off
For example, assume that the wiring system on a model with three input elements is set as follows:
Input elements 1 to 3: Three-phase, four-wire system (3P4W). Input elements 1 to 3 are assigned to a single
wiring unit ΣA.
• ON
The measurement range and sync source can be set independently for each input element included in a
wiring unit.
• OFF
The measurement range and sync source of input elements 1 to 3 are set to the same setting. This is
convenient because when you are measuring a three-phase device, you can set the range and sync source
settings of all input elements included in a wiring unit simultaneously.
Settings That Are Shared between Input Elements When Independent Input Element Configuration Is
Turned Off
• Measurement range (including auto range on or off)
• Direct current input or external current sensor input
• Valid measurement range
• Synchronization source
• Input element group for harmonic measurement (applies to models with the simultaneous dual harmonic
measurement option).
Settings That Can Be Configured Independently Even When Independent Input Element Configuration Is
Turned Off
• External current sensor conversion ratio (option)
• Scaling values (VT ratio, CT ratio, and power coefficient)
• Input filters (line filter and frequency filter)
These settings can be configured independently for each input element regardless of whether independent input
element configuration is turned on or off.
How Settings Are Aligned When You Turn Independent Input Element Configuration from On to Off
When independent input element configuration is switched from on to off, the measurement range, valid
measurement range, and sync source settings of each input element in a wiring unit (ΣA, ΣB, or ΣC) are
changed as follows:
• The measurement range is set to the greatest of the measurement ranges of the input elements assigned to
the same wiring unit. The external current sensor input range has precedence over the direct input current
range.
• The auto range on/off settings are changed to match the setting of the input element whose measurement
range is highest. If multiple input elements are set to a common highest measurement range, the setting of
the input element with the smallest input element number takes precedence.
• In the valid measurement range settings, all measurement ranges are enabled (selected).
• The synchronization source for a wiring unit is set to the input element whose number is the smallest of the
elements in the unit.
2 Fundamental Measurement Conditions