Project Overview:
Urban sewage treatment plants plays an important role in the comprehensive management of ecological civilization construction, energy conservation and emission reduction. Since the distance between the sewage treatment projects in each station farther, and influenced by the external environment, the ability to communicate and network devices requires high stability, therefore, ring Industrial Ethernet switches has been more widely used to the field of communication transport layer.
The sewage treatment plant service area is mainly residential sewage and industrial wastewater, serving a population of 15 million people, covering an area of 30 square kilometers. The sewage treatment plant to protect the quality of drinking water sources of the inhabitants of the region plays a vital role. Therefore, the quality of the sewage treatment plant system operation and stability becomes extremely important position.
The sewage treatment plant automation control system is divided into two levels, the first level is the control and management level (control center), the second stage is the process control level (field control layer). Because the sewage treatment plant and pumping station with a far distance. Therefore, using two CK6062 industrial Ethernet switches connect to PLC from transformer room to built two redundant ring networks, PLC site were used six Comark Ci-PF12-S bus repeaters to build dual-redundant communication. respectively, and sludge dewatering plant and ultraviolet disinfection plant consisting of a fiber optic ring network to solve the scene interference, lightning and distance problem, also to ensure the two separate bus transport stability and independence of the system.

Network Structure:

（Figure 1）

Device configuration and number:

CK6062-S 6*100M electrical interfaces, 2*SC fiber interfaces, IP30, 35mmDIN Qty: 4pcs

Ci-PF12-S Support PROFIBUS protocol, single mode ST interfaces, IP30, 35mmDIN,DC12-36V Qty: 6pcs

Industrial Ethernet switches main function introduction:

No main structure design, easy to use

6*100 Base-TX interface, 2*100 base - FX interface

Fiber interface support ring network redundancy, healing time < 20 ms

Support based on the VLAN ports, IEEE802.1 Q VLAN

Support QoS - IEEE802.1p/1Q

Support static multicast filtering and Port Trunking

Support port mirroring

Supportr the rate limit bandwidth and the broadcast storm protection function

Support 8k MAC address table

Support two-way alarm input I/OPort, 1 way alarm outputI/OPort

Normal temperature (0 ~ 70 ℃), extend the wide temperature model (40 ~ 85 ℃)

Conclusion:

This system used fiber optic repeater and Ethernet optical fiber transmission, it can solve the electromagnetic interference, ground loop interference and lightning damage problem, greatly improving the control signal reliability, security and confidentiality, also solved the problem of the short transmission distance at the same time, it break traditional user is limited to use expensive products from abroad, Shenzhen Comark provide localized service, the most cost-effective products, its can replace the imported similar products.