A customer in a research and testing environment was seeking to upgrade their data acquisition capabilities. Their existing systems, built around bespoke data acquisition software and separate DAQ boxes, were used to monitor processes involving corrosive fluids. While functional, this setup was becoming cumbersome to manage and scale. The core requirement was to find a modern, integrated solution capable of simultaneously logging signals from a diverse array of legacy analogue instruments. A single, unified interface for data capture and display was essential to streamline their operations.
The application required a system that could handle a mix of instrumentation with different output types. Specifically, the setup needed to accommodate:
- Up to ten 4-20mA absolute and differential pressure transducers.
- Two K-type thermocouples, which utilised specialised 1/8-inch Hastelloy probes compatible with the corrosive media.
- A centralised interface for connecting all sensors to a laptop for monitoring and data logging.
- The ability to directly power the 4-20mA loop-powered transducers, simplifying the overall system wiring.
The proposed solution was a compact multichannel controller and datalogger from the MultiCon CMC-99 series. This device provided an all-in-one platform to replace the customer’s multi-part DAQ and bespoke data acquisition software system. The specific hardware configuration was selected to meet the exact channel count and signal type requirements of the application, while also offering capacity for future expansion. A unit was configured with a 16-channel current input module to handle the ten 4-20mA pressure transducer signals and a 4-channel thermocouple input module for the two K-type probes. The selected power supply module not only powered the main unit but also provided an integrated 24V DC output, capable of directly powering the customer’s 4-20mA transducers. This feature was a significant benefit, as it eliminated the need for external power supplies for each sensor, thereby simplifying the installation wiring and reducing potential points of failure.
The true advantage of the solution lay in its software architecture, which is built around the concept of “Logical Channels”. Each physical input, whether a 4-20mA signal or a thermocouple, was assigned to a dedicated logical channel within the device. This abstraction layer provided immense flexibility; each channel could be independently named (e.g., “Upstream Absolute Pressure”), have its specific engineering units defined (e.g., psi), and be individually scaled or filtered. This capability was crucial for managing the diverse sensor mix in a single, coherent system.
These configured logical channels were then organised into a “Group” for unified visualisation. This allowed the operator to view all critical process variables—both pressures and temperatures—simultaneously on one screen in various formats, such as numerical values, bar graphs, needle-style dials, or time-based charts. For connectivity, an advanced communication module provided an Ethernet port for direct network connection to a PC. This enabled the use of the complimentary DAQ Manager software to download, visualise, and archive the recorded process data. Furthermore, the device features an integrated web server, allowing authorised personnel to remotely monitor the process values in real-time from any standard web browser on the network, a significant enhancement over the previous localised bespoke data acquisition software system.
CMC-99 Compact Multichannel Datalogger
- Part No: CMC-99-PS42-ETU-I16-TC4-{E}-1B1
- Power Supply Module: PS42 (85V ÷ 260V AC/DC power supply module, 24V sensor supply output, RS-485 port)
- Communication Module: ETU module (includes 1 x USB Host, 1 x Ethernet 10 Mb/s)
- Slot C – Input/Output Module: I16 (16 x current input module)
- Slot B – Input/Output Module: TC4 (4 x TC input module)
- Base Model: base unit, front USB port
Data Logging License Key
- Part No: LKS-99/141