Siemens SIPROTEC 6MD665, Manual

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3.1 Installation and Connections
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6MD665 Manual
C53000-G1876-C103-3
relay is delivered, these jumpers are set according to the name-plate sticker. Gener-
ally, they need not be altered (see also ordering data in the Appendix).
Life contact The life contact of the device is a changeover contact from which either the opening
or the closing contact can be attached to the K3 and K4 device connections via a plug-
in jumper (X40). The assignment of the plug-in jumper to the contact type and the
spatial arrangement of the jumper are described in the following.
Rated currents The input transformers of the devices are set to a rated current of 1 A or 5 A with jump-
ers. The positioning of the plug-in jumpers has been executed in the factory according
to the indications on the rating plate. All jumpers must be set for one rated current, i.e.
respectively one jumper (X61 to X63) for each input transformer and additionally the
common jumper X60.
Should you perform a change here, you must not forget to communicate this change
to the device also via the parameter Transformer current I, secondary in the measuring
transducer packets.
Control voltage for
binary inputs In the delivery status, the binary inputs are set in a way ensuring that a direct current
equalling the supply voltage is set as control variable. If the rated values differ from the
power system control voltage, it may be necessary to change the switching threshold
of the binary inputs.
To change the switching threshold of a binary input, a jumper must be reallocated in
each case.
Note
If binary inputs are used for trip circuit monitoring, note that two binary inputs (or a
binary input and a replacement resistor) are connected in series. The switching
threshold must lie clearly below one half of the rated control voltage.
Replacing inter-
faces The serial interfaces are replacable. The interfaces which can be replaced, and how
this is done, is described in the Interface modules section.
Terminating serial
interfaces If the device is equipped with a serial RS485 interface or PROFIBUS, they must be
terminated with resistors at the last device on the bus to ensure reliable data transmis-
sion. For this purpose termination resistors are provided on the PCB of the CPU pro-
cessor module and on the PROFIBUS interface module which can be connected via
jumpers. Both jumpers must be always plugged in identically.
The termination resistors are disabled on unit delivery.