Schweitzer Engineering Laboratories SEL-701, Instruction Manual

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701 Motor Protection Relay
Date Code 20010719
Commissioning
Relay Commissioning Procedure
7.6
NOTE:
The MOT R , MST R , and SER R commands should only be
used at initial installation. Do not reset the motor operating
statistics or SER buffer following routine maintenance unless
you are very familiar with the use of the data contained in
these buffers and are certain that the data is no longer
needed.
Table 7.1 Serial Port Commands that Clear Relay Data Buffers
Step 15. When it is safe to do so, start the motor.
Step 16. Verify the following ac quantities using the front-panel Meter
Values\Instantaneous Meter or serial port
METER command:
Phase current magnitudes should be nearly equal.
Phase current phase angles should be balanced, should have
proper phase rotation, and should have appropriate phase
relationship to their phase voltages.
The positive-sequence current magnitude, I1, should be nearly
equal to IA, IB, and IC.
The negative-sequence current magnitude, I2, and residual
current magnitude should both be nearly zero.
NOTE:
If the relay reports I1 near zero and I2 nearly equal to IA,
IB, and IC, there is a phase rotation problem. Verify the relay ac
current connections and the phase rotation setting, PHROT. A
nonzero 3I0 meter value indicates a phase current polarity
connection problem.
Table 7.1 Serial Port Commands that Clear Relay Data Buffers
Serial
Port Command Task Performed
MET RD Resets Demand Meter Data
MET RP Resets Peak Demand Meter Data
MET RE Resets Energy Meter Data
MET RM Resets Max/Min Data
LDP R Resets the Load Profile Data
HIS R Resets Event Report and History Command Buffers
MOT R Resets Motor Operating Statistic Buffers
MST R Resets Motor Start Trend Data
RLP Reset Learned Motor Parameters
SER R Resets Sequential Events Record Buffer