Category Archives: Industrial Automation

Convert Allen Bradley Logix 5000 Time to Unix Time (Epoch)

My favorite time format for time stamping events is to use Unix Time.  The AB Logix 5000 controllers offer time in a format that is similar, but requires some conversion.  Here is code for a RedLion device that does that … Continue reading

Posted in Industrial Automation | Tagged , , , , , , , | Comments Off on Convert Allen Bradley Logix 5000 Time to Unix Time (Epoch)

Convert Unsigned Integer to Float

I’m working with a RedLion device that treats integers as signed, and they don’t provide the function needed to convert an unsigned integer into a floating point.   Here is some code that will treat the 32 bit register as … Continue reading

Posted in Industrial Automation | Tagged , , , | 1 Comment

Debounce Code for Logix 5000

Here is a way to debounce the on and off signals in a Logix 5000 PLC:

Posted in How-To, Industrial Automation | Comments Off on Debounce Code for Logix 5000

Intrinsic Safety Demonstration

At Turck‘s intrinsic safety seminar hosed by Automated Dynamics, I saw a very good demonstration of how safety barrier devices work:  They limit energy to a level that a spark produced will be too weak to ignite the gas surrounding the … Continue reading

Posted in Industrial Automation | Tagged , , , , , | 1 Comment

No Arc Flash PPE Required for PLC Panels

I’ve heard that PLC and I/O panels need to be designed to exclude 120V wires or circuits because of arc flash requirements.  On Table 130.7(C)(15)(A)(a) of the 2015 NFPA 70E, it states as long as no exposed energized equipment over … Continue reading

Posted in Industrial Automation | Tagged , , , | Comments Off on No Arc Flash PPE Required for PLC Panels

Program to Email Memory Contents of Redlion HMI for Troubleshooting

The Redlion HMIs have the capability of creating and deleting files on the flash memory card and emailing out files.  The program below is called from a button on a diagnostics screen.  This is used to collect the contents of … Continue reading

Posted in Industrial Automation | Tagged , , , | Comments Off on Program to Email Memory Contents of Redlion HMI for Troubleshooting

IDEC PLCs and HMIs

While the info is fresh in my mind, I thought I’d make a few notes from the 3-day training class on IDEC PLCs and HMIs. In General: Excellent hardware quality compact size low cost software is inexpensive (free with purchase … Continue reading

Posted in Industrial Automation | Tagged , , , | 1 Comment

Use Linear Regression to Find Slope of Many Datapoints

Here is the implementation of a program that analyses several days worth of data coming from a sensor that might change a tiny amount over that time.  We were interested in how much of a change over time occurred, so … Continue reading

Posted in Industrial Automation | Tagged , , , | Comments Off on Use Linear Regression to Find Slope of Many Datapoints

Current Time as a Fraction of Current Year

I had the need to represent time as a fraction of a year, so I came up with this little program to do the conversion for me.  (using in Redlion Crimson 3)

Posted in Industrial Automation | Tagged , , , , , | Comments Off on Current Time as a Fraction of Current Year

Undocumented Secrets of Integrating BACnet MSTP

After too many hours of struggling though trial and error, packet sniffing, and lots of various materials found on the Internet, I have uncovered a few very important secrets that were not readily apparent in the official vendor documentation I had … Continue reading

Posted in Industrial Automation | Tagged , , , | 2 Comments