Hi everyone, I am maintenance tech at small company with many PLC or computer controlled machines. My boss would like to have the machine run time monitored and reported. By run-time, I mean, of the available machine hours, how many hours is it actually processing parts.
Typically, I know which circuit to tap via inductive switch or dry contact. By I do not know the steps to get the information on to or out of either a microcontroller or Raspberry Pi. We can push this info via WiFi to our facility network, and our IT guys can grab the log file from there and pull it into reports or dashboards. I would like something I can program on the bench, then mount to din rail and leave it alone.
Any ideas or projects you have seen that you could point me to? Thank you!
Hello dlutke, Welcome to the DigiKey TechForum.
I did some searching, and did not see a match for your application.
Hopefully one of the engineers will have some suggestions, and will add to this post.
Thank you for the effort!
AFX00002 or something similar might be a thing to look at; basically a PLC device compatible with the Arduino ecosystem, and not too ridiculously expensive.
Thank you rick_1976. I did some reading about it, that may be the ticket, along with the web service, it give use the opportunity to create front end as well.
Please allow me to present a few related ideas for your considerations:
Life: Industrial control systems tend to have very long lifetimes. When making decision, it’s best to think 10 to 20 years down the road. While it’s impossible to clearly identify future trends, we should take the time to explore options with the IT department.
Tendency toward centralized control / monitoring: The Industrial literature points to trends in what are known as “edge controllers.” These devices blend attributes of the traditional PLC’s real-time control with advanced networked capabilities.
Scope creep: Once you successfully report out run time, you will be asked to report out other items such as number of units produced, rejects, and other statistics such set up time, and tolerance.
Plane text has longevity: Some data formats have longer longevity than others: There is something to be said for plane-text communication. Other considerations such as an open-source database are desirable.
Cyber security: Exploits will only become worse with age. This is especially problematic with industrial controls. The long lifetime of equipment coupled with the extreme expense of commissioning a new real-time control system is a guarantee for cyber susceptibility. This is mitigated by network that is soft on the inside and crunchy on the outside with things like data diodes, firewalls, and vigilant user controls to prevent outside access.
Skills gap: Qualified personnel skilled in industrial control are hard to find. Worse, it takes decades to grow the skills in house.
Other missing ideas.
There are many options available to you. As @rick_1976 pointed out, a low cost parallel, monitoring PLC could be used. Such a system will address some, but not all, of the items on the list. The parallel system has the advantage of low cost and ease of installation.
Other options are available including:
Modification to existing PLCs for serial or ethernet output. For example, you may be able to program the existing PLCs to output a SQL string directly to the plant’s wired network. Many PLCs have the option of installing a serial or ethernet module. This option would allow you to report out all PLC functions.
Remote radio may be used. Phoenix Contact is a DigiKey supplier featuring a line of industrial radios that that may interest you. This includes cell capabilities. Please see this document for ideas.
Hybrid future looking solution. It may be useful to select a low cost, yet limited option, for existing equipment. As time move forward, you may want to modify your equipment and or purchase new equipment with the desired networking features.