Siemens SWT 3000 Equipment Manual page 310

Processing Unit Module
7.1 Functions of the PU4 module
[dwbliswt-051011-01.tif, 2, en_US]
Figure 7-2
IFC Interface command module
PU4 Processing unit module
LIA Analog line interface
DLE Digital line equipment
LID Digital line interface
EN100 Ethernet EN100 module for IEC 61850
SSI Serial synchronous interface
iLAN Internal LAN
CSPi Central signal processing unit
PS Power supply
At the receive side, the incoming commands are received in the VF range or digital depending on the oper-
ating mode.
These commands are converted into one of the following cases:
•
Binary protection commands, and forwarded to the IFC-D/P module for command output.
•
GOOSE command and forwarded to EN100 module for command output
Apart from coding and decoding of protection commands, the PU4 also performs various monitoring func-
tions.
For example, the receive and transmit levels are fed via measuring points to the PU4 where they are compared
with the permissible values. If these levels are not reached, the PU4 activates an alarm. In the normal situa-
tion, that is, if there is no protection command transmitted, the guard signal is sent to the remote station.
Loss of a wanted signal (command or guard tone) triggers a receive alarm at the receive side and causes the
relay outputs of the device to block. This alarm state can only be canceled by receiving the guard signal again.
310
Block Diagram of the SWT 3000 Unit Integrated in the PowerLink
Smart Communication, SWT 3000 Teleprotection, Equipment Manual
C53000-G6040-C605-1, Edition 03.2020