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Controlling LabJack T4 and T7 with 3rd party HMI or PLCs

Human Machine Interface (HMI) devices are widely used in the world of industrial automation.  In general, they collect information and allow data to be presented visually on a screen that can be placed close to machine operators or monitoring personnel.  They are typically devices running some flavor of a computer operating system (typically Windows or a flavor of Linux).  Sometimes vendors will also choose to roll their own operating system.  Historically, they didn't typically have any built-in I/O however modern HMIs are constantly changing shape and function to adapt to industry trends and customer requirements.  They usually require some amount of system set-up and potential assistance from the original vendor to do so and are usually highly configurable. There aren't many HMIs that can be calibrated (or easily re-calibrated on a yearly basis) and there are few with high quality analog inputs capable of integrating directly with hard to acquire low-voltage analog signals.

Modern programmable logic controllers (PLCs) are similar in that they are devices that can be programed and collect data from remote devices as well as some now having I/O built directly onto the device themselves.  They don't typically have screens and are usually programed using proprietary software packages and old-school ladder logic.

Given that with both of these devices, a common technology is used (Modbus TCP) and some questions people are asking themselves: a few common problems are seen:

  • Can you collect data and display the results with out the need of a computer?
    Yes. HMIs are built to collect data from devices and display values on small screens.
  • How do you utilize these technologies to collect and display (in real-time) accurate and calibrated data? 
    Typically HMIs have Ethernet connections and can be connected to large ethernet networks.  Connect everything together, define and configure each device's IP address, and start displaying information.  If high speed responses to system inputs need to be given, consider a distributed data collection architecture.
  • How do you isolate electrical damage from rippling through out a system and ensure that data is always being collected properly?
    HMIs can be expensive and so can data collection devices.  Ethernet connections provide a high amount of isolation between data collection devices and LabJack's repair policy combined with our calibration service could be part of the right answer to a complicated question.
  • How do we avoid vendor lock-in and ensure that our system is capable of being easily upgradable long into the future?
    Selectively choose communication protocols and hardware that support industry standards from companies that offer excellent customer support.

LabJack's T-Series devices are Modbus slave devices that are implement Modbus TCP servers (more details).  They are capable of running Lua Scripts and because Modbus TCP is an industry standard protocol, they can be controlled by a wide array of 3rd party software packages as well as hardware devices.  This protocol's open-ness and flexibility allows industrial system architects to build and design highly customized systems that don't depend on a single vendor's hardware and empowers implementers/R&D professionals with the freedom of choice when it comes to data collection and industrial measurement and automation applications.

A few known HMI devices from other industrial automation companies that have been successfully used to control LabJack's Ethernet DAQ devices capable of Modbus TCP communication:

The Raspberry Pi and SBCs

As mentioned in a multitude of online articles such as "Industrial IoT HMI for Raspberry PI and Linux" by The Manufacturing Connection. The Raspberry Pi can be configured to be a HMI device (with its touch-screen) or by connecting it to an HMI supported monitor and running an applicable Modbus Client/SCADA software package on it. Many of these software packages feature all of the required features of today's IIoT 4.0 ecosystem such as: Real-Time tags, trending/data historians, scripting, SQL/Database support, graphical data displays, alarms, notifications, etc. Feel free to contact us or reach out to one of the many applicable software vendors and ask about how LabJack devices can be used with their systems.

In order to keep up with latest industry standards, best practices, and various other potential ISO standards, don't forget to keep your data collection devices calibrated!

Advanced HMI's 8", 10", 12", 15", and 17" Industrial HMI Panels:

Advanced HMI is a company based out of South Carolina USA that produces HMI devices and also offers custom hardware/gui software integration services that allow data to be collected from Modbus TCP devices. Their panels start at a price of $1,175 (5/28/2019) for a 8" touch screen that runs windows 10 and appear to have all of the capabilities of running LabJack's T-Series software applications right out of the box for debugging and simple data acquisition/logging purposes. Contact Advanced HMI for more details on their products and services.

Horner Automation's Horner XL7:

This device advertises the ability to collect data from Modbus TCP devices (see their published User Manual in the Documentation and Resources section) an allow data from LabJack's unique mixture of high quality analog inputs and a slew of other I/O features (Stand Alone Operation via Lua Scripting) to be visualized neatly on a touch screen interface.

Schneider Electric's Magelis STO Compact HMIs

Schneider Electric's compact HMIs support the Modbus TCP protocol, and therefore can collect data from the LabJack T4 and T7. LabJack T-Series devices can be configured with a static IP addresses and connected directly to some of the best HMI/PLC devices out there. Read through our Basic Networking & Troubleshooting Application Note and let us know if you have any questions.


Have any other 3rd party HMI ideas, suggestions or integration questions? Leave a comment below or contact us.