Ethernet; Rs485 - Siemens SENTRON 7KM PAC2200 Product Manual

2.5.1

Ethernet

Permits communication via the following protocols:
● Modbus TCP
The device can be configured via Modbus TCP
● Web server (HTTP)
Protocol can be used to read out the measured values via web browser.
● SNTP
The SNTP (Simple Network Time Protocol) is used to automatically synchronize the internal
clock with a time server within the network.
Three function modes are available:
● No synchronization.
● Date/time synchronization via device request
The IP address of an NTP server must be configured. With this, the PAC2200
automatically requests the current time from the server and resets its internal clock, if
necessary.
● Date/time synchronization via SNTP server broadcast
The PAC2200 receives broadcast time frames, which are sent from an NTP server. This
is practical, if the internal clocks in several devices in the same network
should be synchronous.
If the IP address of the NTP server has been configured, the PAC2200 only responds to
these telegrams. Furthermore, it can send a request to the server, if necessary.
● DHCP
Stands for "Dynamic Host Configuration Protocol". Protocol for obtaining network settings
from a DHCP server. Network settings are assigned automatically.
2.5.2

RS485

Enables communication via MODBUS RTU protocol. This interface features simple topology
and high immunity against EMC interference.
The data is transmitted differentially via two wires A and B. The third wire "COM" serves as
the common ground potential.
Grounding of the cable shield:
The serial Modbus data cable should be shielded. The shield should be connected to
protective ground at one end of the cable at least.
Grounding of the COM line:
PAC2200
Equipment Manual, 12/2019, L1V30415167B-03
Description
2.5 Communication
27