GE MI-869

CHAPTER 7: RECORDS MOTOR START RECORDS
869 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL 7–3
Motor Start Records
When a motor start status is detected by the 869 relay, a start data record is triggered and
begins to sample and record the following parameters at a rate of 1 sample every 200ms:
• True RMS values of the phase A, B and C currents (Ia, Ib, and Ic).
• Average of true RMS values of the three-phase currents (Iavg).
• True RMS value of the ground current (Ig).
• Current unbalance (%).
• True RMS values of the phase A-N, B-N, and C-N voltages (Van, Vbn, and Vcn) if VT is
Wy
e connected.
• True RMS values of the phase A-B, B-C and C-A voltages (Vab, Vbc, and Vca) if VT is
delta connect
ed.
• Three-phase real power.
• Three-phase reactive power.
• Three-phase power factor.
• Thermal capacity used (%).
• Frequency.
• Motor status.
1-second pre-trigger data and 59-second post-trigger data are recorded. The data record
ignor
es all subsequent triggers and continues to record data until the active record is
finished.
A total of 6 records are stored in the relay. Record # 1 is the baseline record; it is written to
only by the f
irst start that occurs after the user clears the motor start records. Records #2
to 6 are a rolling buffer of the last 5 motor starts. A new record automatically shifts the
rolling buffer and overwrites the oldest record, #2.
The record files are formatted using the COMTRADE file format. The files can be
down
loaded and displayed via EnerVista 8 Series Setup software. All the files are stored in
non-volatile memory, so that information is retained when power to the relay is lost.
The viewing, customizing and saving the Motor Start Records is the same as the Transient
Re
cords.
Clearing start records (RECORDS > CLEAR REC
ORDS > MOTOR START RECORDS) clears the
stored files. The date and time are recorded when clearing. An event ‘Clear Start Rec’ is
sent to the Event Record. The records can also be cleared using EnerVista 8 Series Setup.
Path:
Records > Motor Start Records