Apply 2 times setting current if possible and record operating time.
Check correct indication, trip output, alarm contacts, waveform record.
Note that these elements can be set to directional.
Table 9-6 P.U. D.O. & Timing Tests
Ph. Dir Char.
(NI EI VI
LTI,
DTL)
I
set
(A) Tm Operate Current Operate Time
P.U.
(Amps)
D.O.
(Amps)
Tol 2 ⋅ I
set
(sec)
5 ⋅ I
set
(sec)
Tol
CT4
Check correct indication, trip output, alarm contacts, waveform record.
Note that these elements can be set to directional.
If VTS action is set to Block, this option should be tested. Apply balanced voltage and current. Reduce a-
phase voltage to cause a VTS condition. Increase a-phase current and check that the element does not
operate.
If VTS action is set to Non-Directional, this option should be tested. Apply balanced voltage and current.
Reduce a-phase voltage to cause a VTS condition. Increase a-phase current and check that the element oper-
ates at its normal setting. Reverse the voltage phase direction whilst checking that the element does not reset.
Wattmetric Protection
The Wattmetric Earth Fault protection requires that the GS current setting is exceeded, the residual
power setting is exceeded and the directional element operated, simultaneously.
During testing of the 67GS Wattmetric Power setting it is essential that the current setting is also
exceeded. This can usually be achieved by applying current which is above setting to the GS input whilst
applying single phase voltage, in anti-phase with the current, to any 1 phase to neutral voltage input. In this
way, the wattmetric power is equal to the product of the applied current and applied voltage and can be
adjusted by adjustment of the voltage magnitude.
Wattmetric Power
Setting
Current Applied I
op
Dir Operate Voltage
V
op
Calculated P
op
I
op
⋅
V
op
During testing of the 67GS I
res
Select residual current setting it is essential that the Wattmetric Power
setting is also exceeded. This can usually be achieved by applying the test current to the GS input whilst
applying a nominal single phase voltage, in anti-phase with the current, to all 3 phase to neutral voltage
inputs. In this way, the wattmetric power is equal to the product of 3 times the applied voltage and the
applied current and this should always be greater than the Wattmetric Power setting.
Inverse Time Overcurrent (51GS)
It will be advantageous to map the function being tested to temporarily drive the relevant pickup output in the
Pickup Config sub-menu in the Output Config menu as this will allow the Pickup LED to operate for
the function.
Gradually increase current until Pickup LED operates.
Apply 2 times setting current and record operating time.
Apply 5 times setting current and record operating time.
Compare to calculated values for operating times.
Functional Tests
9.9 Protection Functional Tests
480 Reyrolle 7SR5, Overcurrent Protection Device, Device Manual
C53000-G7040-C014-1, Edition 11.2019
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