In some cases you may need to flash a bit in your PLC program. Let’s say that you have an HMI that is not capable of flashing an alarm notification. In that case, you may use the PLC program and one of a number of ways to flash a bit. You can then use that bit on the HMI to indicate a flashing al...

In the previous lesson we talked about the different ways to generate timing pulses or flashing bits within your PLC program. Also, in other lessons, some time ago, we discussed how to generate pulses using timers. In this lesson, we are going to recap how to create these pulses and work with the...

In this lesson, we are going to discuss how to handle alarming. Visual alarm indicators may be lights on the plant floor or alarm symbols on an HMI screen and as common industry standard, an indicator should flash when an alarm occurs but only until acknowledged. After acknowledgement, the indica...

In the previous lesson we began writing some code that would post and acknowledge alarms per industry standard. As you know, we ran into a little problem with the code clearing the alarm after acknowledgement but it would not re-post the alarm in constant mode. In this lesson, we are going to tro...

In this lesson we are going to energize 16 lamps at the same time, with the press of a switch. After some time delay, we want the lamps to turn off one at a time, one every second, until all of lamps are de-energized. We will be using the shift instruction to accomplish this task. After we write ...

In the previous lesson we began writing some code that would turn on 16 lamps, all at once, with the press of a switch. Once the switch is released, after a short delay, the lamps are supposed to turn off, one by one, every second until they are all off. We simulated the code only to find that we...

In the previous lessons we have been working with some code that turns on multiple lamps with the press of a single switch. After a short time delay, the lamps are supposed to turn off one at a time, one every second until all of lamps are turned off. As you know during writing and testing, we ha...

In previous lessons, we have been working with the shift instruction and have written a few lines of code that will turn on and off some PLC outputs in a specific order. We’ve been writing code to create different patterns to turn on and off 16 lamps. We started out using 2 switches and eventuall...

We have been working, for a few lessons, on a PLC shift instruction to turn on and off some lamps, in different sequential patterns. We will continue to modify our program from the previous lesson, where we worked with the logic such that we wanted to turn on the first lamp and after a delay, tur...

We have been writing some code that will turn on and then of some lamps, one at a time, beginning from the top of a display to the bottom. We want to start this sequence with press of a button. After the lamps sequence to the bottom and prior to the last lamp turning off, we want the sequence to ...

We created a series a while back called Turning on PLC Outputs in Sequential Order and that series had 9 parts. We have again opened up that series to address the many questions and comments among the RealPars students. This was an extensive series that walked you through the programming of turni...

This is a continuation of the series about Turning on PLC Outputs in Sequential Order. In the previous lesson, we refreshed your memory on the logic that we had written as well as the general idea of how we want the program to function. In this lesson, we are going to delete a little bit of code ...