Reassembly - Siemens Siprotec 7VK61 Manual

Mounting and Commissioning
3.1 Mounting and Connections
RS485 Termination
For bus-capable interfaces a termination is necessary at the bus for each last device, i.e. terminating resistors
must be connected. On the 7VK61 device, this concerns the variants with RS485 or PROFIBUS7/DNP inter-
faces.
The terminating resistors are located on the RS485 or PROFIBUS interface module, which is on the C-CPU-2
board (Serial no.1 in Figure 3-3 and 3-4), or directly on the PCB of the processor board C-CPU-2 (see margin
heading "Processor Board C-CPU-2", Table 3-7).
Figure 3-11 shows the C-CPU-2 PCB with the layout of the modules.
The board with configuration as RS485 interface is shown in Figure 3-13, the module for the Profibus/DNP in-
terface in Figure3-14.
For the configuration of the terminating resistors both jumpers have to be plugged in the same way.
On delivery the jumpers are set so that the terminating resistors are disconnected.
The terminating resistors can also be implemented outside the device (e.g. at the terminal block), see Figure
3-15. In this case, the terminating resistors located on the interface module or directly on the PCB of the pro-
cessor board C-CPU-2 must be disconnected.
Figure 3-15

3.1.2.5 Reassembly

The assembly of the device is done in the following steps:
• Carefully insert the boards into the case. The mounting locations are shown in Figures 3-3 and 3-4. For the
model of the device designed for surface mounting, use the metal lever to insert the processor board C-
CPU-2. Installation is easier with the lever.
• First plug in the plug connectors of the ribbon cable onto the input/output board I/O and then onto the pro-
cessor board C-CPU-2. Be careful that no connector pins are bent! Don't apply force!
• Connect the plug connectors of the ribbon cable between processor board C-CPU-2 and the front panel to
the front panel plug connector.
• Press plug connector interlocks together.
• Put on the front cover and screw it onto the housing.
• Put the covers back on.
• Re-fasten the interfaces on the rear of the device housing. This activity is not necessary if the device is de-
signed for surface mounting.
202
Termination of the RS485 Interface (External)
SIPROTEC, 7VK61, Manual
C53000-G1176-C159-3, Release date 05.2009