Siemens Reyrolle 7SR5, Руководство пользователя

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59 Overvoltage Protection – 3 Phase
Where more than 1 overvoltage (59) elements are being used with different settings, it is convenient to test
the elements with the highest settings first. The elements with lower settings can then be tested without disa-
bling the higher settings.
If the
O/P Phases
is set to
All
, the voltage on all phases must be increased simultaneously. Otherwise the 3
phases can be tested individually. There is a common setting for to select the voltage to be measured as
phase-phase or phase-neutral. If the DTL setting is short, starting from nominal voltage, slowly increase the
applied 3P or VL1 test voltage until the
Pickup
LED (temporarily mapped) is on. The LED should light at
setting
Volts
±5 % decrease the input voltage to nominal
Volts
and the LED will extinguish. Record the
reset voltage to check the
Hysteresis
setting. If the DTL setting is long, the operate level can be checked by
applying 100 % of setting to cause operation followed by setting minus the
Hysteresis
setting to cause
reset.
Connect the relevant output contact(s) to stop the test set. Step the applied voltage to a level above the
setting. The test set should be stopped at the
Operate Time
setting ±5 % test the other phases by repeating
the above if necessary.
Phase Setting
(Volts)
U/O DTL
(sec) Hyst. D.O.
(calcu-
lated) P.U.
Volts D.O
Volts Op. Time @ 1.2
⋅ V
set
(OV) @
0.5 ⋅ V
set
(UV)
UV
Guard Toler-
ance
V
A
(V
AB
)
V
B
BC
AB
)
V
C
CA
AB
)
Element Blocking
The
Under/Over Voltage
elements can be blocked by
Binary Input Inhibit
and
VT Supervision
.
This functionality should be checked.
Element BI Inhibits VT Supervision
59-1
59-2
59-3
59-4
When testing is complete reinstate any of the disabled functions.
59N Neutral Voltage Displacement
The normal voltage source for the
Neutral Overvoltage
59N function is V
rated
, calculated from the applied
3 phase voltage inputs but it can be configured to operate from the single phase V4 input. To test, apply test
voltage to 1 phase input.
Definite Time (59NDT)
If DTL setting is small, gradually increase single phase voltage until element operates.
If DTL is large apply 0.9 times setting, check for no operation, apply 1.1 times setting, check operation.
Apply 2 times setting voltage if possible and record operating time.
Phase Setting (Volts) Delay (sec) P.U. Current
(Volts) Op. Time @ 2 ⋅
V
set
Tolerance
E
Check correct indication, trip output, alarm contacts, waveform record.
9.10.16
9.10.17
Functional Tests
9.10 Protection Functional Tests
Reyrolle 7SR5, Transformer Protection Device, Device Manual 441
C53000-G7040-C015-1, Edition 11.2019