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TB MRI(K)3-C 03.02 E
6.4.6 Checking the auto reclosing function
The auto reclosing function can only be tested by means
of an auxiliary relay simulating the C.B. and a push but-
ton for manual start. In order to simplify testing, the sig-
nificant settings of the devices and the value of the test
current are provided as follows:
I>
= 0,8 x I
N
I> +CHAR
= DEFT
tI>
= 2 s
I>>
= 1,2 x I
N
tI>>
= 0,5 s
SHOT
= 1
tF
= 1,5
tD1
= 5 s
tD2
= 10 s
tCI
= 0,2 s
tR
= 10 s
tF + I>,I>>(IE>,IE>>)
= 1ST
CB (tCBFP)
= 2 s (EXIT)
f
N
= 50 Hz or 60 Hz
Relay assignment:
refer to default settings
AR-assignment:
I>
= YES
I>>
= YES
The test circuit must be set up in accordance with Figure
6.1. First the push button is pressed. The auxiliary relay
picks up and the LED CB lights up. With the settings of
the devices as shown above, a test current of 1.5 x I
N
should be injected on phase L1. When the pickup value
is exceeded, tripping takes place at once and the LEDs
I>> and L1 light up red.
The auxiliary relay releases again. The device changes
into the "Starting" status. Now the dead time is running
and the LED tD1 lights up green. After expiration of the
dead time the LED tCI briefly lights up and the auxiliary
relay trips again.
The display shows "CLOS". The LED tR lights up red. The
LED tR signals that the reclaim time is running. Once it
has expired, all LEDs extinguish except for the LED CB,
and the display shows "ISEG" again. This completes a
successful AR simulation.
Note:
After the relay has tripped, the test current should be
switched off as quickly as possible. Otherwise, there is
the danger that the switch failure protection device CBFP
picks up. If switching off quickly is impossible, tCBFP
must be set to "EXIT".
6.4.7 Checking the circuit breaker position
First the digital inputs have to be assigned the relevant
functions. In order to recognised the circuit breaker posi-
tion, at least the CB position ON or the CB position
OFF must be configured. The correct display of the CB
LED can be found in chapter 4.7.10.
Behaviour with AR function
If the circuit breaker is set to position ON, the LED tR will
light up for the duration of the set blocking time and the
display shows "MANU". The CB LED shows a red light.
Behaviour without AR function
If the circuit breaker is set to position ON, the light of
the CB LED will be red.
6.4.8 Checking the AR blocking function
First it must be ensured that the function is assigned to a
digital input. If the digital input is activated, the 0
←
I
will light up red.
6.4.9 Checking the external blocking and
reset functions
By means of the external blocking input, it is possible to
block all protective functions. To give an example, the
blocking function of the phase current high set element is
described.
This can be tested by first setting the parameter for the
phase current high set element to „BLOC“ and then con-
necting the auxiliary voltage to to the digital input re-
served for this purpose.
The phase current low set element I> should be set to
EXIT for this test. Inject a test current which could cause
a high set (I>>) tripping. Observe that there is no trip of
any assigned output relay of the high set or low set ele-
ment.
Remove the auxiliary supply voltage from the blocking
input. Inject a test current to trip the relay (message
„TRIP“ on the display). Interrupt the test current and apply
auxiliary supply voltage to the external reset input of the
relay (terminals C8/D8). The display and LED indica-
tions should be reset immediately.
