Siemens 7XV5673 Device Manual page 222

Glossary
I
IEC
IP
IP address
J
JavaScript
K
Keep Alive
L
LED
LSB
M
MAC Address
MBAP
MBAP Header
Modbus
Modbus RTU
Modbus TCP
Modbus UDP
MSB
N
NO
NTP
R
Response time
RJ45
222
International Electrotechnical Commission, standards organization; Communica-
tion standard for substations and protection equipment
Internet Protocol
Addresses in computer networks based on the Internet protocol
Script language mainly used by Web browsers
KeepAlive on TCP level is a feature intended to verify the availability and
functioning of the communication partner (client) and to maintain a TCP network link
if the network is inactive.
The server sends KeepAlive messages (TCP packets without data) to the client in
regular intervals (KeepAlive time) while the network is inactive, and the client
responds to these messages.
If the client does not respond to a KeepAlive message, the server assumes that the
link is down or the client is inactive and closes the TCP link.
Light-Emitting Diode
Least Significant Bit
Media Access Control address: Hardware address that clearly identifies the device
on the network.
Modbus Application Protocol
Header of a Modbus TCP message consisting of these 4 parts: Transaction identi-
fier (2 bytes), protocol identifier (2 bytes), length (2 bytes), unit identifier (1 byte).
The Modbus protocol is a communication protocol based on a client-server
architecture.
Modbus Remote Terminal Unit: Modbus protocol type for transmitting data over
serial networks (for example RS485)
Modbus Transmission Control Protocol: Modbus protocol type for transmitting data
as TCP/IP packets; TCP port 502 is reserved for Modbus TCP.
Modbus User Datagram Protocol: Modbus protocol type for transmitting data as
UDP/IP packets
Most Significant Bit
Normally open: Type of relay
Network Time Protocol: Standard for synchronizing clocks in computer systems
using packet-based communication networks
Time the output needs to react to a signal change at the device input. Time
measured from an instant change at the AC input until the corresponding change of
a DC output quantity has reached 90% of its final value.
Ethernet plug connector
SICAM I/O Unit, 7XV5673, Device Manual
E50417-H1040-C484-A3, Edition 05.2012