Category Archives: PLC Basics

PLC Fiddle Timer Challenge

Timers are present in just about every PLC program that I have seen. A timing chart is the secret behind understanding of the timer that you need in your application. Making a timing chart before writing the program will ensure that all of the information will be accounted. The secret to using timers is a good review of using these timing charts.

PLC Fiddle has three different timing instructions for us to use in our programs. On-Delay, Off-Delay and Retentive Timers. We will discuss the timer parameters and the three different instructions. Our timer challenges will help you gain a good understanding of how timers work in the PLC. Let’s get started. Continue Reading!

Productivity 1000 Series PLC Data Handling Instructions Part 2

Data handling instructions are used to perform movement and manipulations of the memory in the programmable logic controller. The Productivity 1000 Series PLC has fifteen different data handling instructions that can be used in a wide variety of applications. In this second part we will be looking at the following instructions:
Lookup Table (LKUP) – Find a value within an XY Table by looking at the intercept of a referenced X Axis value and Y Axis value.
Pack Bits (PKB) – Convert up to 32 Boolean Tag Bits or Constant Bits into an Output Integer Tag.
Pack Word (PKW) – Convert up to four 8 bit tags or two 16 bit tags, or four Constants into a 16 or 32 bit Destination Tag.
Shift / Rotate Bits (SFR) – Shift or Rotate Bits of a Tag or Constant value.
Sign Magnitude (SMAG) – Convert Sign Plus Magnitude data type values to 2’s Complement or Convert 2’s Complement data type values to Sign Plus Magnitude.
UnPack Bits (UPKB) – Convert up to a 32 Bit Integer Tag or Constant into Boolean Tags.
UnPack Word (UPKW) – Convert one 32 bit or 16 bit source tag into four 8 bit tags or two 16 bit tags.
A review of data handling instructions part 1 can be found here. Here is a link to the video.
Let’s get started with the Productivity 1000 Series PLC data handling instructions part 2. Continue Reading!

Productivity 1000 Series PLC Data Handling Instructions Part 1

Data handling instructions are used to perform movement and manipulations of the memory in the programmable logic controller. The Productivity 1000 Series PLC has fifteen different data handling instructions that can be used in a wide variety of applications. In this first part we will be looking at the following instructions:
Absolute Encoder (ABSE) – Encoder input using Gray Code or Binary Code
Compare Values (CMPV) – Compare two different tags and determine if equal, greater than or less than.
Copy Data (CPD) – Copy tags from one location and place in another.
FIFO / LIFO (FILI) – First in first out / Last in first out
First Bit On/Off (FIB) – Determines first bit on in a series of bit tags.
Inc / Dec (INC) – Increment or decrement a tag by a number.
Logical Bits (LOG) – Perform logical operations on Boolean input tags.
Logical Words (LOGW) – Perform logical operations on tags.
In part 2 of data handling we will continue with additional data handling instructions.
Let’s get started with the Productivity 1000 Series PLC data handling instructions. Continue Reading!

PLC Fiddle Basic Gate Ladder Logic

Last time we discussed the free virtual plc simulator called PLC Fiddle. It will enable you to create simple PLC ladder logic code within your browser. This is an ideal way in understanding PLC concepts for industrial automation. All of the basic PLC instructions that come with most plc units have been incorporated in this virtual PLC software.
http://accautomation.ca/plc-fiddle-online-editor-and-simulator-in-your-browser/
PLC Fiddle Video – This will demonstrate the basic functions of the PLC simulator.
Understanding and creating your own programmable logic controller programs in ladder can be fun. We will be starting with the basic gate logic circuits and convert these to ladder logic.
We will be looking at the AND, OR, NAND, NOR, EXOR and EXNOR logic circuits using PLC fiddle. This will get you involved in leaning and understanding PLC programming. Let’s get started. Continue Reading!

Productivity 1000 Series PLC Math Instructions

Math instructions are used to perform mathematical calculations. The Productivity 1000 Series PLC has math instructions that can be used in a wide variety of applications. We will be looking at the Data Statistics (DATA) and the Math Editor (MATH).

Your automation system that you implement may involve these instructions. As a system integrator you will require the use of these instructions in your commissioned programs.
Let’s get started with the Productivity 1000 Series PLC Math Instructions. Continue Reading!

Cofaso 7 PLC Design and Overview

Cofaso 7 is a computer aided engineering (CAE) solution software package. Its special system technology with direct access to applicable logic for each schematic allows industry design and documentation for all solutions. Electrical engineering project tasks will become easier with Cofaso 7. This parameter controlled system is available in 13 languages and supports all the common windows versions.
Cofaso 7 meets all global evaluation standards. It offers complete authoring and editing of electrical engineering documents. Some of the features in the package include: Cross-references, wiring lists, terminal diagrams, terminal connection diagrams, interconnect diagrams, PLC cross references, mounting plate design and more.

Cofaso provides flexible editing features:
XML, EXF and graphics interfaces such as DXF guarantee data interchange with other CAx systems and ensure the integration of cofaso into the unified production chain. Article data of any kind be imported or incorporated. An intelligent article number search function provides an additional aid to locating components used in the diagram.
We will be creating a PLC drawing with 5 outputs. These outputs will be connected to another box with the same reference numbers. We will also show the automated connection list. Anytime a reference name is changed all document items will change for that reference. Let’s get started. Continue Reading!

Productivity 1000 Series PLC Counter Instructions

A majority of programmable logic controller (PLC) programs will include a counter instruction. The Productivity 1000 Series PLC has a couple of different counter instructions for your program. Under the data handling instructions we have the increment / decrement instruction (INC). We could use this with the compare contact (CMP) instruction that we discussed in our Contact and Coil Instructions (Video) to create a counter application.

The productivity suite software has a Simple Counter (SCNT) and the Counter (CNT) instructions. We will be reviewing these instructions and looking how to implement then in our ladder logic program. Let’s get started. Continue Reading!

Productivity 1000 Series PLC Timer Instructions

Just about every programmable logic controller (PLC) program will include a timer instruction. The Productivity 1000 Series PLC has several different timer instructions for your program. We discussed the timed coil (TMC) and flasher coil (FLS) last time as part of the contacts and coil discussion. (Contact and Coil InstructionsVideo)

We will now look at using the Simple Timer (STMR) and the Timer (TMR) instructions in the productivity suite software. Let’s get started. Continue Reading!

Productivity 1000 Series PLC Contact and Coil Instructions

The Productivity Suite Software consists of more than 82 instructions divided into 13 categories for the PLC. Contacts and Coils are two of the categories of instructions. Contact instructions include NO / NC, NO Edge / NC Edge and Compare. Coil instructions include Out, Set, Reset, OR Out, Flasher, Debounce, Timed, Toggle, Program End and No Operation.

We will be looking at these instructions in the Productivity 1000 series PLC. Adding to our favorite instructions helps us to organize the instructions. We will also look at organizing your favorite instructions. Let’s get started. Continue Reading!

Productivity 1000 Series PLC Numbering Systems and Tag Database

The Productivity Suite Software allows us to use tags in the PLC. Tags are a method for assigning and referencing memory locations within the programmable logic controller. They allow a more structured programming approach and are stored within a tag database. The tag database is stored in the memory of the Productivity Series of PLC’s from Automation Direct. Do not over think tags. Tags are just names that we assign to variables of any data type stored in the PLC memory.

We will be looking at data types available in the Productivity PLC and how to use the tag database. Let’s get started. Continue Reading!