Measurement - Mitsubishi Electric CBV2-A01D1 Instruction Manual

4.2 Measurement

Voltages input to the relay are measured and converted into freely set VT primary voltages, then indicated
in the display.
(1) Real time measurement
The effective voltage input to the relay under steady state is displayed.
(2) Max. record
The maximum effective voltage is recorded and stored.
The max. record will be all cleared when "aux. power supply OFF" or "max. record reset" operation is
made.
(3) Fault record
In the event of system fault, the effective voltage and waveform data that have been measured at the
time when one of the protection elements operates to issue an output signal are stored. Data of up to
five phenomena can be stored and displayed for each phase.
With "aux. power supply OFF", only the waveform data will be cleared and the effective voltage data
will remain. With "fault record reset" operation, however, both of the data items will be all cleared.
(Records older than the 5
Item No.
211
212
213
214
215
The following fault waveform data can be collected if a communication card is installed:
Data sampling cycle
Data storing capacity (for
a phenomenon)
Permissible setting range
Collected data
Output contact
th
phenomenon will automatically be cleared.)
History
st
1 phenomena
nd
2 phenomena
rd
3 phenomena
th
4 phenomena
th
5 phenomena
Item
Fixed to the electric angle of 30° of rated frequency
224 cycles of rated frequency
(Data point: 224×360°/30° = 2688 points)
224 cycles before trip ~ 224 cycles after trip
The range for data collection can be set by cycle within the
"data storing capacity" in the "permissible set range".
Collected data
Up to 224 cycles
Permissible set
←224 cycles before trip
ON
OFF
Trip occurs!
Figure 4.4 Concept of recording fault waveform
Sequence of recording
Latest fault record data
↓
↓
↓
Oldest fault record data
Specification
Data sampling cycle
224 cycles after trip→
13 PCKN-OIL738