Siemens 7UT51

7UT51 v3
Bench Testing
16
PRIM-2330C 177
16.8 Tank Leakage
Protection Testing
(if Available)
One of the additional measured current input IA or IB
can be allocated to the tank leakage protection,
Address 2827. Depending on the input used, the
pickup value of the protection is set under
Address 2703 (Insensitive CT A), setting range 0.10 to
10 times rated relay current, or Address 2704
(Sensitive CT B), setting range 10mA to 1,000mA
(independent of the rated current).
For testing the tank leakage protection, this function
must be parameterized as operative,
On
or
Block Trip
Rel
in Address 2701.
Apply test current to the current input which is
assigned to the tank leakage protection.
Testing with higher currents should be performed
dynamically. It should be confirmed that the relay picks
up at 1.1 times setting value and does not pickup at
0.9 times setting value.
When the set pickup value is exceeded, pickup
indication “
Tank Gen. Flt
” occurs (must be
marshalled/programmed, see Chapter 13).
After the set time delay in Address 2725 (default = 0
sec.), a trip signal is issued and the annunciation
“
Tank Gen. Trip
”, LED 8 (must be marshalled/
programmed, see Chapter 13).
16.9 External Trip Function
Coupling Testing
Two desired signal from external protection or
supervisory units can be connected into the
processing of the 7UT51 via binary inputs. Like the
internal signals, they can be annunciated, delayed and
transmitted to the trip matrix.
The external signals can be checked when they have
been configured as EXISTENT/ENABLED under
addresses 7830 and/or 7831 and parameterized as
operative in addresses 3001 and/or 3101,
respectively. Additionally, binary inputs must be
allocated to these functions.
After the binary input of the tested external trip
function has been activated, annunciation
>Ext. Trip *
is given. Annunciation “
Ext. * Gen. Flt”
is the actual
fault event annunciation.
After T-DELAY (addresses 3002 and 3102)
annunciation “
Ext. * Gen. Trip
” will occur.
For the input of annunciations of the Buchholz
protection (when the relay is used as transformer
protection), three binary inputs are reserved. When
these are allocated to physical inputs, their correct
function can be tested also.
Test currents larger than four (4) times
In or 15A (Sensitive input) may overload
and damage the relay if applied
continuously.
Observe a cooling down period!