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1. WHAT IS THE METHOD USED BY THE PLC TO WRITE A LADDER LOGIC PROGRAM IS CALLED HOW TO
2. WHAT IS THE METHOD USED BY THE PLC TO WRITE A LADDER LOGIC PROGRAM IS CALLED FULL

Confused? For a single digit, BI (two)-nary means two possible outputs. What is Binary?īinary is part of the M-ary system of representation when M is the total number of results. Therefore, it is much simpler to use the Binary concept in Number Systems to represent the outputs. The result may also vary by the tiniest amount and it is already considered a different output.

The “Maybe” in between the “Yes or No”, or the “Medium” in between “High or Low”. Instead of 0 or 1 only, we have values in between. In analog, we consider an INFINITE number of values. This simplifies input-output relationships as compared to the analog side of things. This means that it’s either “True or False”, “High or Low”, “Yes or No”, “0 or 1”. Logic circuits are digital, so they produce outputs that are discrete in nature. PLC Programming was based on Relay Logic, and Relay Logic was based on-well, the fundamentals of logic. The next step is actually designing a program for your controller to execute the steps required to perform your automated control system.īut first, you have to know some logical fundamentals that will allow your system to create decisions on its own.

I found this helpful video that actually shows a control problem to solve: Lastly, you would want to control an input valve to regulate the flow of water into your tank.

WHAT IS THE METHOD USED BY THE PLC TO WRITE A LADDER LOGIC PROGRAM IS CALLED FULL

In this case, because there are water levels involved, you must use level sensors: One for the Full level and one for the Near Empty level. What do you do?īecause you have clearly identified what outcomes you want along with the conditions, you now have to think the appropriate types of sensors and output devices that you must use. You want the tank to fill up until it is full and then automatically refill one the water level is near empty just to maintain the pressure. This means that the final outcomes must be determined clearly along with the conditions that determine the outcome.Īlso, the input and output devices must be clearly identified.įor instance, you want a control system for your water tank. 4.5 Equivalent Ladder Diagrams for Logical Functionsīefore you start programming your PLC, or in fact any controller, you must begin with the end in mind.3.4.2.1 Normally open and Normally Closed Inputs.3.4.1 Parts of a ladder logic diagram and how it works.3.1 What is a PLC programming language?.3 IEC61131-3 Standard: PLC programming languages.

WHAT IS THE METHOD USED BY THE PLC TO WRITE A LADDER LOGIC PROGRAM IS CALLED HOW TO

Rung 0004:ī3:0/0 and T4:2 enabled to turn on Timer T4:3 to Set the timers (T4:0, T4:1, T4:2 and T4:3) preset to 2sec using move block. Rung 0003:ī3:0/0 and T4:1 enabled to turn on 元 (O:0/1 ) and Timer T4:2 to turn on 元. Rung 0002:ī3:0/0 and T4:0 enabled to turn on L2 (O:0/1 ) and Timer T4:1 to turn on 元. Rung 0001:ī3:0/0 enabled to turn on L1 (O:0/0 ) and Timer T4:0 to turn on L2. Start/Stop PB latched with memory B3:0/0.