‘Smart’ devices have transformed nearly every aspect of our home and work life: smart phones, smart televisions, smart appliances, even smart homes. Process monitoring and control instrumentation is no exception. The online monitoring systems available today are far superior to versions available just 10 years ago providing more measurements more reliably, and at a reduced cost. As a result, there are more opportunities for enhancing the performance and efficiency of water resource recovery facilities (WRRF).
YSI’s solution for online process monitoring, IQ SensorNet, is a network-based, modular system. Each of the four basic components of the system, sensors, cables, modules, and controllers, has features that make implementation simple and effective. The main topic of this blog is the universal controller. The other three components are (or will be) discussed in separate blog articles.
The brain of a modern process monitoring system is the universal controller. ‘Smart’ sensors with signal processing make dedicated analog transmitters obsolete but an interface is still needed for measurement display and programming operating functions, for example, programming the sensor measurement range and analog output scaling. Furthermore, implementation of digital communications allows for a universal configuration of the interface and the ability to manage multiple channels with one device – the universal controller.
The IQ SensorNet offers three universal controller options: a 4-channel controller (IQSN 182), a 20-channel controller (IQSN 2020 XT), and a controller module without a display (MC2). The right controller for your application depends on the number of measurements and monitoring locations, the configuration of the existing SCADA system, and the type of communications.
IQSN 182 is the point-to-point configuration solution for control and display of up to 4 channels and is the lowest priced of the controller options. IQSN 182 is a good choice for relatively small applications with 1 or 2 monitoring locations needing 4 or fewer measurements each. It is also a good drop-in replacement for existing monitoring systems where power drops and output wires are installed and only basic controller functions are required for implementation into a facility’s SCADA system. However, the configuration has to be repeated at each measuring location increasing hardware requirements and cost for larger systems.
IQSN 2020 XT is a network solution for managing up to 20 measurements with a single controller substantially reducing hardware requirements and cost of equipment. It is the best choice to provide the most functionality with the least amount of hardware. Installation costs may also be substantially reduced because fewer conduit runs from the controller to the SCADA system are required. Instead, monitoring locations are linked with a single 2-conductor cable that conveys both power and communications as shown in the figure below.
Instead of providing a display at every monitoring location, up to three 2020 XT units are deployed throughout the system. One unit is the controller; the other units are display terminals and back-up controllers that will automatically take over control functions if the other units malfunction or are removed. In addition, the 2020 XT includes datalogging capability. For example, up to 90 days of data for 20 measurements logged at 5 minute intervals can be stored. The remaining storage is dynamically displayed as datalogging is programmed allowing for quick and simple optimization.
Another added feature is a multi-function USB port. The USB port allows connection of a USB memory device for transfer of logged data, logbook entries, calibration history, and configuration. Saving and restoring system configuration data allows quick recovery from unintended programming changes. The USB port also can serve as an electronic ‘key’ to simplify access to restricted functions. The 2020 XT controller costs a little bit more than the 182 controller, but if there is more than one measuring location the controller hardware cost is less for 2020XT. Therefore, 2020XT is a good solution for any facility.
The third controller option is the MC2 “controller in a box”. The system can be accessed using free IQ Software Pack CONNECT software or from up to three 2020 XT terminals. The MC2 is the same configuration and has all the features of the 2020 XT. In addition, the MC2 features a built-in barometer for air pressure compensation of dissolved oxygen measurements and a built-in Ethernet/LAN interface. The MC2 is a good solution for customers with an existing SCADA system that want a monitoring system with advanced communication technology. The MC2 communicates directly over Ethernet/IP with Allen Bradley’s most popular PLC platform and is also programmed for Modbus TCP application protocol. In addition, the monitoring system can be accessed remotely over the internet with a customer-supplied router and the free IQ Software Pack CONNECT. Current measured values can also be viewed using a web browser on a PC or smartphone. For all this, an MC2 controller module is actually less expensive than a 2020 XT controller although most customers will also purchase at least one 2020 XT as a terminal and back-up controller.
Additional Blog Posts of Interest:
Can Smart Devices Enhance Resource Recovery Facilities? Part 2
Wastewater Aeration Control - Energy Cost Savings Examples
Myths and Realties: Ammonium Based Aeration in Wastewater
Troubleshooting Nitrification and Denitrification in Wastewater