User`s manual

3 ChromLAN Gateway CGW – Elan Gateway EGW
With the Gateways CGW and EGW, Siemens PGC302, RGC202 and PGC102 Gas-Chromatographs as
well as the series 6 Continuous Gas Analyzers can be linked to an Ethernet network.
The Gateway has 2 Serial Ports:
There is a port for the Ethernet and a serial port for RS485 or RS232.
• The Ethernet port consists of a 10BaseT interface for a twisted cable pair that typically ends in a
network hub.
• The serial port can be configured as a RS485 or RS232-serial interface. This serial port functions
as a ChromLAN or ELAN master for a single specific analyzer or all analyzers connected in a
loop.
Design:
The gateway is integrated in an aluminum housing. The housing has also DIN-Rail mounting capabilities
and has therefore versatile mounting capabilities. It only requires 24 V DC power.
3 Network with ChromLAN Gateway CGW
• The Gateway CGW can be installed inside the chromatograph. Using a cable, the CGW is
connected with one of the serial ports on the PCPU-2 on one side and with the external Ethernet
on the other side. This solution ensures the highest availability because in case of failure only that
specific analyzer will be off-line and not an entire network loop.
• The Gateway CGW can also be used externally by connecting several (up to 15) chromatographs
to the RS-485 serial port. With that configuration a network loop can be build. Keep in mind, that
in case of a CGW failure, all chromatographs in that network loop will be off-line.
Comment: The Ethernet Gateway does not change the functionality or capabilities of the ChromLan
network. Because ChromLan is a Master/Slave network, the transmission capacity depends directly on
the scanning rate, which is the speed with which the individual participants are queried. The second
deciding factor is the transmission speed to the actual analyzer. Because the GC’s are communicating to
the CGW using RS232/RS485, the maximum speed is limited to 38400 Bit/sec.
Because the Ethernet concept does not limit the number of Workstations anymore, possible capacity
limitations with large networks can be circumvented by applying several Workstations and dedicate each
workstation to only certain specific participants in the network. This is especially advisable when querying
reports and chromatograms. All data are administered by a common database.
2 • ChromLan/ELAN - Gateway Ethernet - RS485/RS232