ABB RELION RET670, Commissioning Manual, Page: 303 / 328

Section 14 Commissioning and maintenance of the fault
clearing system
14.1 Commissioning tests
During commissioning all protection functions shall be verified with the setting values
used at each plant. The commissioning tests must include verification of all circuits by
highlighting the circuit diagrams and the configuration diagrams for the used functions.
Further, the settings for protection functions are tested and recorded carefully as outlined
for the future periodic maintenance tests.
The final testing includes primary verification of all directional functions where load
currents is checked on the local HMI and in PCM600. The magnitudes and angles of all
currents and voltages should be checked and the symmetry verified.
Directional functions have information about the measured direction and, for example,
measured impedance. These values must be checked and verified as correct with the
export or import of power available.
Finally, final trip tests must be performed. This involves activation of protection functions
or tripping outputs with the circuit breaker closed and the tripping of the breaker verified.
When several breakers are involved, each breaker must be checked individually and it
must be verified that the other involved breakers are not tripped at the same time.
14.2 Periodic maintenance tests
The periodicity of all tests depends on several factors, for example the importance of the
installation, environmental conditions, simple or complex equipment, static or
electromechanical IEDs, and so on.
The normal maintenance practices of the user should be followed. However, ABB's
recommendation is as follows:
Every second to third year
1MRK 504 165-UUS -
Section 14
Commissioning and maintenance of the fault clearing system
Transformer protection RET670 2.2 ANSI 297
Commissioning manual