Function
The
earth fault and short circuit indicators usually incorporate a relay
for remote indication with a potential-free closing contact. This
contact of the earth fault or short circut indicator is connected to
the transmitter / encoder (up to five earth fault or short circuit
inidcators can be connected to a transmitter).
Within the transmitter each earth fault or short circuit inidcator
automatically receives a code.
In case of an earth fault or short circuit a relay contact is closed in
the short circuit indicator.
Thus the transmitter receives a fault
message. The code name is assigned to this message and transmitted to
the receiver. The transmission of the data can be accomplished via
radio contact or via the telephone net.
The indication, respectively
the evaluation of the data received by the receiver, can be performed:
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1) indication via relay contact
After a fault indication,
the output relay will respond according to
the input relay.
For monitoring 5 stations,
one transmitter and one receiver are
necessary (fig. 1)
2) indication
via display screen
The fault message coming
from the transmitter is picked up by a
computer and indicated via a display screen.
For monitoring 5 stations,
one transmitter is needed.
For the equipment of the receiving side, one modem receiver and one
computer
with screen is required. 80 stations can be monitored
(fig. 2).
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