Radio towers are used to extend the range of radio signals that provide communication between people or companies. Since radio towers are spread out over wide areas, they are particularly difficult to monitor. Usually, field engineers are required to drive to each site for regular status checks. A more efficient solution would be to monitor each tower remotely. Traditionally, this involves the use of a PLC to monitor and control a number of devices on-site.

System Requirements
A client needed to monitor many individual items for a set of unmanned radio towers. In their system, sensors would be used to detect motion, smoke, fuel tank levels, door activity, power generator status, and lighting system status. In addition, a local alarm system would be installed and would need to be managed. While PLCs are traditionally used for this type of I/O device monitoring and control, the client wanted a different solution for remote management over IP networks. The system needed to be easy to maintain remotely and should provide real-time information to central station. The I/O controller needed to satisfy the following requirements:

• Simple local device control capability
• Implementation that does not require programming
• Time-stamped data for I/O device status
• Efficient use of Ethernet bandwidth
• Software that can easily manage thousands of stations

System Description
The ioLogik E2210 served as the I/O controller for unmanned monitoring at each radio tower. If the attached sensors detect motion and a door opening, the ioLogik E2210 will activate the alarm buzzer, trigger an IP camera, and send out an alarm message with real-time stamp over the network to the control center. The ioLogik E2210 also sends a message to the control center if the fuel level sensor detects that the level has dropped below a certain threshold.

Establishing the control logic required no programming, thanks to the ioLogik's patented Click&Go logic. The architecture allowed complete monitoring of critical items at the radio tower without requiring a field engineer to visit each site. Engineers could operate from a control center and simply respond to any alarm messages.

Project Implementation
	ioLogik E2210 Active Ethernet I/O server with 12 digital inputs, 8 digital outputs
	EDS 205 5-port unmanaged Ethernet switch
	VPort 351 1-channel industrial video encoder supporting full motion MPEG4/MJPEG

Why Moxa?

• Real-time stamp for alarm messages
• Proactive alarm messages that reduce bandwidth
• Click&Go logic for local device control without programming
• Industrial-grade IP camera
• Rugged industrial Ethernet switch

Conclusion
Moxa is the one of leading companies providing industrial communication solutions. The Active Ethernet I/O solution in this application is an excellent alternative to using traditional PLCs for remote monitoring of unmanned sites. Active Ethernet I/O not only allows local device control, but also provides efficient Ethernet connectivity. Furthermore, Moxa offers all the products necessary for a complete, tightly-integrated solution for the whole system.