Siemens Reyrolle 7SR5, Руководство пользователя

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Table 9-10 Results for testing 87BD with 2 current sources
87BD Initial
Setting 87BD 1st Bias
Slope Setting W1 Current (⋅ I
rated
)
0 1 1.5 2 2.5
W2 Current (⋅ I
rated
)
0.1 0.1 0.1 1.11 1.66 2.21 2.76
0.2 0.2 0.2 1.22 1.83 2.44 3.06
0.3 0.3 0.3 1.35 2.03 2.71 3.38
0.4 0.4 0.4 1.5 2.25 3 3.75
0.5 0.5 0.5 1.67 2.5 3.33 4.17
0.5 0.6 0.5 1.86 2.79 3.71 4.64
0.5 0.7 0.5 2.08 3.12 4.15 5.19
Selected Settings Test Results
0 1 1.5 2 2.5
Phase A Pickup
Phase B Pickup
Phase C Pickup
Differential Highset 87HS
Differential Highset
can be tested by single phase secondary current injection. 87HS settings will
usually be higher than the continuous thermal rating of the relay current inputs and equipment or test proce-
dure should be arranged in such a way that the short term thermal withstand of the relay current inputs is not
exceeded during testing. 50 % of relay setting current can be injected into each of the 2 winding inputs simul-
taneously to achieve a differential current level of 100 % if test current is limited by test equipment capacity.
The settings used for
Secondary Injection
test purposes should be:
W1 ICT Multiplier 1x
W1 ICT Connection Yy0,0°
W2 ICT Multiplier 1x
W2 ICT Connection Yy0,0°
W3 ICT Multiplier 1x
W3 ICT Connection Yy0,0°
These settings ensure a 1:1 ratio between the injected current and the relay setting. Note that operation of
the element can be achieved at a lower level of current if a higher
ICT Multiplier
setting is applied.
During testing the operate current can be monitored on the relay in the
Instruments
menu.
Primary Injection Testing
Primary injection is recommended to prove the relay connections, CT polarity and settings before putting the
protection scheme into service. Primary injection is essential to fully prove the connections of the
Biased
Differential
and
REF
protections. To provide a useful test the relay should have the final site specific
settings applied for primary injection tests.
i
i
NOTE
It is important before carrying out any primary injection to ensure appropriate CTs are shorted to avoid
operation of mesh corner or busbar type unit protection. If the injected primary current is large enough, the
bus zones protection may operate.
Sufficient primary current to prove the connections and settings is required so that a minimum secondary
current of about 10 mA rms circulates in the relay inputs. This is difficult to achieve using high current primary
injection equipment due to the relatively high impedance of the transformer windings. An alternative method
is to apply 415 LVAC to one side of the transformer with a short circuit applied to the other side. The external
Functional Tests
9.10 Protection Functional Tests
Reyrolle 7SR5, Transformer Protection Device, Device Manual 449
C53000-G7040-C015-1, Edition 11.2019