Disassembly - Siemens SIPROTEC 4 7VK61 Manual

Type of Contact for Output Relays
Some input/output boards can contain relays whose contacts can be set to have normally closed or normally
open contacts. To do so, you have to move a jumper. The following sections under "Switching Elements on
Printed Circuit Boards"describe for which relays on which boards this is the case.
Exchanging Interfaces
The serial interfaces can only be replaced in devices designed for panel flush and cubicle mounting The
following section under margin heading "Replacing Interface Modules" describes which interfaces can be
exchanged, and how this is done.
Terminating interfaces with bus capability
If the device is equipped with a serial RS485 port, the RS485 bus must be terminated with resistors at the last
device on the bus to ensure reliable data transmission. For this purpose, terminating resistors are provided on
the PCB of the C-CPU-2 processor board and on the RS485 or PROFIBUS/DNP interface module which can be
connected via jumpers. The spatial arrangement of the jumpers on the PCB of the processor module C-CPU-2 is
described in the following sections under the margin heading "Processor Module C-CPU-2" and on the inter-
face modules under "RS485 Interface" and "PROFIBUS Interface". Both jumpers must always be plugged in the
same way.
The termination resistors are disabled on delivery.
Spare Parts
Spare parts can include the backup battery that maintains the data in the battery-buffered RAM when the
voltage supply fails, and the miniature fuse of the internal power supply. Their spatial arrangement is shown
in the figure of the processor module. The ratings of the fuse are printed on the board next to the fuse. When
replacing the fuse, please observe the guidelines given in the SIPROTEC 4 System Description in the chapter
"Maintenance" and "Corrective Maintenance".
3.1.2.2

Disassembly

Work on the Printed Circuit Boards
NOTE
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It is assumed for the following steps that the device is not operative.
!
CAUTION
Caution when changing jumper settings that affect nominal values of the device:
As a consequence, the ordering number (MLFB) and the ratings on the name plate no longer match
the actual device properties.
Where such changes are necessary in exceptional cases, they MUST be marked clearly and visibly on
²
the device. Self-adhesive stickers are available that can be used as supplementary name plate.
To perform work on the printed circuit boards, such as checking or moving switching elements or exchanging
modules, proceed as follows:
•
Prepare your workplace: provide a suitable pad for electrostatically sensitive devices (ESD). Also the
following tools are required:
– screwdriver with a 5 to 6mm wide tip,
– a crosstip screwdriver for Pz size 1,
– a 5 mm socket wrench.
SIPROTEC 4, 7VK61, Manual
C53000-G1176-C159-5, Edition 05.2018
Mounting and Commissioning
3.1 Mounting and Connections
183