GE Multilin G650, Руководство пользователя

Страница: 258 / 639

GEK-113285A G650 Generator Protection & Control System 5-115
5 SETTINGS 5.6 INPUTS/OUTPUTS
5
Table 5–107: SUPERVISION ALGORITHM WITH SIMPLE VOLTAGE SUPERVISION SCHEME
In this table, ON means that the voltage detector V52/a is active, detecting a voltage.
In the first case shown on the table, with closed breaker, voltage is detected by V 52/a sensor, and this means that there is
continuity in the supervised circuit.
As shown on Figure 5–32:, when the relay is not tripped, trip contact F35-F36 remains open. If the breaker is closed, its
auxiliary contact 52a is closed. Therefore, a little current is flowing, about 2 mA, through terminals F15 and F16 through the
voltage detector circuit, which flows through 52/a and the tripping coil 52TC (TC = tripping coil). Current will only circulate
when there is continuity in the whole circuit, so the complete circuit is monitored, and not only the trip coil. This circuit
includes auxiliary 52/a as well as the whole wiring between the battery and the relay tripping terminals, and between these
and the breaker tripping circuit.
For the second case shown on the table, open breaker, its auxiliary contact 52/a remains open, and current cannot flow
through it for detecting continuity. In order to correctly monitor the circuit, a resistor must be used, not included in the
protection, connected in parallel. The value of resistance will be selected so that the V 52/a input circuit minimum detection
current flows, but not as high as to activate the breaker-tripping coil. The figure shows the following equation:
Where:
Vmin Is the minimum voltage, in Volts, expected in the battery (e.g. 80% of Vn)
R Resistance, in kilo ohms.
2 2 mA of approximate current flowing through input V 52/a
As shown in the second case in the table, with an open breaker, as current will flow through R if there is continuity in the
WHOLE tripping circuit, voltage will be detected in input V 52/a.
This works correctly in steady state. However, if the breaker trips, while it is opening, the V 52/a input signal can be
deactivated without this meaning that the circuit is not correct. This is due to the fact that the tripping relay, terminals F35-
F36, short circuits input V 52/a temporarily.
Therefore, if there is a trip signal, it is permitted that no signal will be detected during a period of 1s to allow the breaker to
open, and reopen the tripping relay F35-F36.
STATUS OF INVOLVED ELEMENTS INPUT TO G650 DECISION
CIRCUIT
STATUS OUTPUT
STATUS
(F35-F36) BREAKER
STATUS OPERAND
CONT IP_X_CC11
(VA_COIL2)
V 52/A (F15-F16) OPERAND
CONT IP_X_CC16
(SUP_COIL2)
Healthy Open 52 closed ON ON
Healthy Open 52 open ON ON
Healthy Closed 52 closed OFF ON (if t < 500 ms)
OFF (if t > 500 ms)
Healthy Closed 52 open OFF ON (if t < 500 ms)
OFF (if t > 500 ms)
Faulty Open 52 closed OFF OFF (500 ms delay)
Faulty Open 52 open OFF OFF (500 ms delay)
Faulty Closed 52 closed OFF OFF (500 ms delay)
Faulty Closed 52 open OFF OFF (500 ms delay)