EN_FANOXTD_GUIDE_SIL_OCEFPrimaryDist_SILA_R002.doc 31 / 36
Considering this description, the real thermal image that will support the
relay depending on the injection mode and injection system is shown below:
WAVE FORM
INJECTION MODE
THERMAL RESISTANCE
SINGLE PHASE P-N
4xIn continuously
20xIn during 10 seconds
70xIn during 1 seconds
3-PHASE BALANCED
4xIn continuously
20xIn during 10 seconds
70xIn during 1 seconds
3-PHASE UNBALANCED
1xIn continuously
6.5xIn during 10 seconds
26xIn during 1 seconds
NOTE:
It is checked that thermal image values are re-defined not to exceed the declared value
in the International Standard:
Commisioning recommendation:
•
It is recommended to use Kitcom accessory for relay protection functions settings.
Connect it for setting and disconnect it for testing purpose.
•
Adjust manually current generation value without injecting current to relay, for not
stressing it during adjustment process.
•
Be sure that relay output contact is connected to generator tripping input in order to stop
the generator, hence the current injection, after reaching adjusted tripping time. This
way, relay will only withstand rated injected current during adjusted time at protection
function settings, not maintaining current injection constantly, which could become a
damaging situation for relay, as in other case, the internally handle energy will be higher
than rated one.
•
Not to perform repetitive trips continuously as the stress of the relay will be increased
drastically, especially when high current is being injected on the relay.
By following these recommendations, relay should pass commissioning test successfully. If
commissioning test is performed not following these recommend
ations, manufacturer won’t be
responsible for relay failure.
8.2.
Measurements
The accuracy of the measurement is ±2% on a band of ±20% over the nominal current and ±4%
over the rest of the measurement range. Some examples are shown below:
- Current injected
=> I=1 A:→ ±2% accuracy is complied.
- Current injected => I=2A. As this current value is 20% higher than the nominal current
(In= 1A) → 4% accuracy is complied.