Autarchic Measurement for Testing Diesel Particulate Filters
CAS Data Loggers
12628 Chillicothe Rd., Unit J
Chesterland, OH, 44026
Press release date: September 4, 2012
Delphin TopMessage Data Acquisition and Control Systems
CHESTERLAND OH - CAS DataLoggers recently provided the data acquisition system for a manufacturer developing a wide range of emission-reducing components for refitting into existing vehicles. Along with producing diesel particulate filters in its factories, the company also supplied cold start controllers to reduce emissions in vehicles with catalytic converters, which could be installed without having to interfere with a vehicle's electronics.
The company needed to continually develop new products to offer filters to the widest possible market. The problem was that virtually every new filter required a new design because of the variety of exhaust systems and their varying temperature and pressure operating levels. Despite this, engineers still had to carry out a series of test drives at varying operational profiles to ascertain whether the filters met the required standards. During these test drives, the exact route as well as vehicle speed and idling times needed to be maintained and measured accurately and reliably, along with filter temperature and filter pressure, engine rotation, vehicle position and speed.
The company found that PC-based measurement systems were too unreliable for such a task due to their hard disk and temperature sensitivities, so they had been using a modular system with channels that could be adapted to specific tasks through a variety of components. However, because they needed a lot of modules for measuring, the system became really expensive. Configuration was also difficult and they needed a laptop for recording measurement data. Because recording couldn't take place with chronological synchronism, a lot more work was required when analyzing the data, so there was an immediate need for a replacement system. What the testers needed was a precise, reliable and flexible system for recording measurements during test drives.
CAS DataLoggers installed a Delphin TopMessage data acquisition system in the factory's filtration test area to demonstrate its utility. The TopMessage device was compact and practical, designed to operate independently without requiring any amplifiers thanks to its electrical isolation. Each of its up to 30 analog inputs could be used for RTD, thermocouple, volt or 20 mA signals. CAS DataLoggers also designed a solution using an external converter for the acquisition of engine rotations as well as the capability to measure speed without having to interfere with the on-board electronics. Additionally, a GPS receiver was attached to the data logger's serial port and wrote the appropriate driver. In this way the position, speed and route driven were all acquired in one go - all values were measured and stored with chronological synchronism and at a high resolution. Users recorded several measurements within a second to get an average, eliminating any outliers in the measurement data.
Since regulatory authorities had not yet set any exact technical regulations, limit values were always subject to change - therefore, any measurement system needed to be able to adapt. In modular systems, the complex software usually meant training courses were required to be able to configure the channels. However, the TopMessage's virtual channels made channel configuration easy to learn. Functions which could be quickly set up included communication protocols (GPS), connecting external components (rotation detection via on-board power supply voltage) as well as calculation channels, linearization channels, set point channels, PID controller channels and timer channels.
Configuration and analysis were achieved with just a few clicks: virtual channels enabled an online analysis to take place during the tests without the need for any PC support. For example, the driver could be provided with information on whether the required speed was being maintained or whether engine idling times had remained adequate. ProfiSignal software also projected measurement data allowing that data to then be evaluated. The ProfiSignal Klicks version improved documentation by generating protocols with all relevant data. Creating new testing, trial or processing systems was made easy by the function blocks available, and users could configure them visually with no need for any programming. Program instructions were generated by selection using the mouse. With ProfiSignal Klicks any number of tasks could be configured into projects and applications so that company-wide systems could be organized and managed. Projects provided an overview of current applications in the various departments. Specific process visualization diagrams were also created at just a few clicks enabling observation and operation.
With the right equipment, the solution to the manufacturer's problem was easy - the TopMessage's system's flexibility was the key. Within just a few weeks users were supplied with a new, flexible and easy to use measurement system. As well as analog inputs for temperature and pressure sensors, the data loggers also came equipped with a digital module for rotation acquisition and a driver for the GPS receivers. The 256 MB storage capability provided enough space for measurement data from several thousand kilometers of test drives. The measurement system was easy to install and reinstall - an important factor when taking measurements from many different vehicles. At last count, five TopMessage devices were being used in the tests.
For more information on our Delphin data logging systems, other data acquisition and control devices, or to find the ideal solution for your application-specific needs, contact a CAS Data Logger Applications Specialist at (800) 956-4437 or visit the website at www.DataLoggerInc.com.
CAS DataLoggers, Inc.
12628 Chillicothe Road
Chesterland, Ohio 44026