Data “tags” are essential to any industrial process on the factory floor. They rarely leave the factory floor, but when they do, a great deal can be learned from them for operational queries such as: “What was the state of the system when the tank started leaking?” or, “How efficient was our process last week, and the week before, and the year prior?”
Tags pass over the factory network, as data flowing across wires and through the air; little samples of something, a name and a value. These packages of names and values are known as tags, and they are used everywhere as a primitive unit in the Industrial Internet of Things (IIoT).
The tags originate from sensors. In a factory, sensors monitor tanks, belts, coolers, lights, and pretty much everything else possible. They then transmit signals to a “local” hub computer, acting as the nerves to the computer’s “brain”. In the factory, this computer is often called a PLC, or Programmable Logic Controller. By using its sensors, the PLC detects, calculates, and orchestrates complex tasks. In another environment, this hub computer could be a microcontroller or system-on-chip, like an Arduino or a Raspberry Pi. These computers essentially act as a hub device to translate sensor information to other machines via its network.
To harness and allow the tags to leave the factory floor, Caravela utilizes a secure data gateway appliance. The gateway reads the tags, secures them for transit, and transmits them over the Internet to Caravela’s private cloud or to a public cloud, whichever is more appropriate for the application and ultimate development choices.
There, the tags are stored in a structured database format, which makes it easy to compare information, and also to generate documents for filing appropriate paperwork for compliance or other purposes.
From the database, tags can also be used in any program hosted on servers to create added value through dashboarding or alerting. One such hosted program, Grafana, lets a user create attractive dashboards from their tag data, issue alerts triggered on any logic, and is powerful yet inexpensive open-source software. Any other visualization tool can be used to interface with the data and provide intelligence to the user.
In an industrial water tank application, for example, if the database indicates that the water level is too low, the Grafana software automatically dispatches an email to give the operator real-time instructions how to correct the problem, and a time limit for message acknowledgement before automatic escalation. If the database indicates that multiple parts of the system are malfunctioning, the operator can also look at this data in real time when making decisions about how to proceed. A system operator can also question the database for predictions, such as: “based on the rate of water flowing through Pump A and Pump B, how long will it take before someone needs to fill Tank A?” This kind of information is invaluable for scheduling advance maintenance and keeping performance records for compliance purposes.
The gateway communicates with the PLC over a secure Ethernet network, and is compatible with the majority of factory PLC networks. From its position on the factory network, the gateway “asks” the PLC what it knows about its sensors. The PLC replies with a list of tags, which the gateway inserts into a database.
For security purposes, the gateway is programmed only to talk to a specifically pre-determined cloud over an encrypted VPN. If unable to do that for any reason, it automatically buffers all data tags on a local disk until the secure network connection is re-established. Typically, the Caravela cloud hosts open source PostgreSQL+TimescaleDB database-as-a-service where the tags rest.
The possibilities are only limited by the imagination and understanding of what insights and information are valuable to a user or a customer. Significantly, the data user doesn’t need to be a programmer; graphical tools like Grafana or Tableau exist to “translate” data visually, simply by clicking, although having an IoT engineer does help educate and improve the quality of the end result. Such engineers are trained to speak computer languages, and are skilled in deducing the source of logical errors.
Caravela offers in-house engineering services for the entire IIoT ecosystem; please contact us to start a conversation.