Table of Contents
Advertisement
1MRK 502 035-UEN A
Therefore practically all bigger generators have some dedicated protection which is capable to
detect the first earth fault in the rotor circuit and then, depending on the fault resistance,
either just to give an alarm to the operating personnel or actually to give stop command to the
machine.
7.7
Testing frequency protection functions
7.7.1
Underfrequency protection SAPTUF
Prepare the IED for verification of settings as outlined in section
settings".
Values of the logical signals for SAPTUF are available on the local HMI under Main menu/
Tests/Function status/Frequency/SAPTUF(81,f<)/X:SAPTUF. The Signal Monitoring in
PCM600 shows the same signals that are available on the local HMI.
7.7.1.1
Verifying the settings
Verification of START value and time delay to operate
1.
Check that the IED settings are appropriate, especially the START value and the definite
time delay.
2.
Supply the IED with three-phase voltages at their rated values.
3.
Slowly decrease the frequency of the applied voltage, until the START signal appears.
4.
Note the operate value and compare it with the set value.
5.
Increase the frequency until rated operating levels are reached.
6.
Check that the START signal resets.
7.
Instantaneously decrease the frequency of the applied voltage to a value about 20%
lower than the operate value.
8.
Measure the time delay of the TRIP signal, and compare it with the set value.
Extended testing
1.
The test above can be repeated to check the time to reset.
2.
The tests above can be repeated to test the frequency dependent inverse time
characteristic.
Verification of the low voltage magnitude blocking
1.
Check that the IED settings are appropriate, especially the
and the
2.
Supply the IED with three-phase voltages at rated values.
3.
Slowly decrease the magnitude of the applied voltage, until the BLKDMAGN signal
appears.
4.
Note the voltage magnitude value and compare it with the SMAI set value
MinValFreqMeas .
Generator protection REG650
Commissioning manual
Rotor earth fault protection can be integrated in REG650 among all other
protection functions typically required for generator protection. Instruction
1MRG001910 gives an example of a testing procedure by using COMBIFLEX
injection unit RXTTE4.
MinValFreqMeas in the SMAI preprocessing function.
© Copyright 2011 ABB. All rights reserved
Testing functionality
"Preparing the IED to verify
StartFrequency and the tDelay
Section 7
M16289-2 v6.1.1
M16289-17 v4
M16289-31 v5
M16289-39 v5
71
Advertisement
Table of Contents
