Showing posts with label systems. Show all posts
Showing posts with label systems. Show all posts

Sunday, September 28, 2014

Is Manufacturing Dead In Canada? Not so!

Everywhere you look there are signs of doom for Canadian Manufacturing. Unemployment rate, companies moving or going out of business seems to be a common theme. However we have is an increase in manufacturing output.

How is manufacturing jobs disappearing and output increasing?


Investment in the business


Take a look around. Businesses that are investing in themselves will have the staying power. Those that do not are going to be left behind, wither and die.
How is your company doing?

People
We often hear that people are the greatest asset for the business. What is the game plan? When asked to see or inquire about how they are advancing there employees; you get blank faces. A constant learning environment must be established.
The learning environment includes:

  • How individuals interact with and treat one another. 
  • How information is conveyed 
    • Internet 
    • Intranet
    • Meetings
    • Teams
    • Postings
  • Knowledge of individual contributions
    • Strengths and Weaknesses
  • Recognize how individuals learn (Example: Millennials do not get information from an authority figure.)
    • Customize leaning for individuals

Process
Look at your process from a new born perspective. Inquire and explore why things have to happen in a certain way. Break every step down.
Kipling wrote:
I keep six honest serving men. They taught me all I knew. Their names are What and Why and When And How and Where and Who.
Query your people with questions and listen.

  • If they had more time, what would they work on?
  • What is there biggest challenge?
  • What is bugging them?
  • Are you happy?

Machine
Keep up on the latest machine innovations for your industry as well as others. Know the limitations of each machine. Table new concepts to your learning environment.
If you are to fix the machine then ask

  • Is this the first time this has happened? Will it happen again?
  • How long did it take to troubleshoot the problem? 
  • Is there something we can improve upon?
  • How can this knowledge be shared with operators, maintenance, management?

Automation
There is a reason that this is last on the list. Automation can stand by itself, but it really requires an understanding of each of the items mentioned above before it is successful.
You must understand your people, process and machine before automation can prove to be an asset.


Automation, people, process and machine innovation can happen. It is up to you.

If you have any questions or need further information, please contact me.
Thank you,
Garry

Reference:
Statistics Canada for Manufacturing
http://www5.statcan.gc.ca/cansim/a33?lang=eng&spMode=mainTables&themeID=4005&RT=TABLE

Thursday, August 28, 2014

The Secret Of Getting Rid Of Noise On Your Analog Signal

Allot of times in industrial environments we get noise on the analog signal input to PLC's or other controllers. The noise can be generated by motors, bad wiring, etc.

Placing a 1- 100 uF capacitor on the input signal and ground (common to the cabinet)  will reduce the noise that the input is receiving.


If you have any questions, or need further information please contact me.
Thank you,
Garry

Wednesday, August 27, 2014

Who Else Wants To Lean PLC Programming For Free?

I have always been an old school programmer. Hardware in front of you hooked up to all of the I/O. I have recently looked at the automation direct do-more designer software solution. The Do-More Designer Software will allow you to build your ladder logic, download into a simulator (comes with the software) and run the code. The price of all of this... FREE

I will not get into allot of details because the documention available already will get you through the software step by step.
- Download the software
- Install the software
- Use the YouTube videos for help with getting around the software and making your first program.

The following are several links to help you discover the plc programmer in you:

Automaion Direct - Do-more Programming Software
http://www.automationdirect.com/adc/Overview/Catalog/Software_Products/Programmable_Controller_Software/Do-more_PLC_Programming_Software

http://www.aboutplcs.com/do-more/software/

http://www.aboutplcs.com/do-more/software/simulator.html

The simulator has allot of great features, including PID simulation.

Do-more PLC - How to videos on youtube
https://www.youtube.com/playlist?list=PLPdypWXY_ROoJx-HnK9gj2Z5a-i7th-UK

Update: Here is a video from YouTube about the simulator basic instructions:
http://www.youtube.com/watch?v=ZnRSw3ykW6k#t=274
https://www.youtube.com/watch?v=4JiMzBHPa7E

If you have any questions, or need further information please contact me.
Thank you,
Garry



Thursday, August 21, 2014

Here's a Quick Way to Convert Grey Code into Binary for PLC

Grey Code
Grey Code is used because only one bit of data will change at a time. The following chart shows the conversion of Grey Code to Binary.

NumberBinary CodeGrey CodeNumberBinary CodeGrey Code
000000000810001100
100010001910011101
2001000111010101111
3001100101110111110
4010001101211001010
5010101111311011011
6011001011411101001
7011101001511111000

It is important for absolute encoders because if the power is interrupted the encoder will know where it is within the one bit.

Example:
Power is interrupted when the encoder is between 7 and 8. If we are looking at Binary Code all of the bits would be effected and we would not be sure as to what number we are looking at for the encoder. Therefore we have lost position. In Grey Code only one bit changes so we will still be able to tell if we were on 7 or 8 if the power was interrupted.

The following sample PLC program will convert 4 bit grey code into binary code.
This code was written in an Automation Direct PLC software called Do-more Designer.


Do-more Designer Software
How to use video's for Do-more Designer Software

Contact me for the above program. I will be happy to email it to you.
Thank you,
Garry

Monday, August 18, 2014

What Everybody Ought to Know About PLC (Programmable Logic Controller) Numbering Systems

Programmable Logic Controllers (PLC) are the same as computers. They only understand two conditions; on and off. (1 or 0 / Hi or Low/ etc.) This is known as binary. The PLC will only understand binary but we need to display, understand and use other numbering systems to make things work. Let's look at the following common numbering systems.

Binary has a base of two (2). Base means the number of symbols used. In binary the symbols are 1 or 0. Each binary symbol can be referred to as a bit. Putting multiple bits together will give you something that looks like this: 100101112. The 2 represents the number of symbols/binary notation. Locations of the bits will indicate weight of the number. The weight of the number is just the number to the power of the position. Positions always start at 0. The right hand bit is the 'least significant bit' and the left hand bit is the 'most significant bit'.

Let's look back at our example to determine what the value of the binary number is:
 100101112 =
We start with the least significant bit and work our way to the most significant bit.
1 x 2= 1 x 1 = 1
1 x 2= 1 x 2 = 2
1 x 2= 1 x 2 x 2 = 4
0 x 2= 0 x 2 x 2 x 2 = 0
1 x 2= 1 x 2 x 2 x 2 x 2 = 16
0 x 2= 0 x 2 x 2 x 2 x 2 x 2 = 0
0 x 2= 0 x 2 x 2 x 2 x 2 x 2 x 2 = 0
1 x 2= 1 x 2 x 2 x 2 x 2 x 2 x 2 x 2 = 128
 100101112  = 1 + 2  + 4 + 16 + 128
 100101112  = 151
Note that the we just converted the binary number to our decimal numbering system. The decimal numbering system is not written with a base value of 10 because this is universally understood.
To be sure we have the concept down, let's take a look at our decimal numbering system the same way as we did the binary.

Decimal has a base of ten (10). The symbols are 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9. 
15110 =
1 x 10= 1 x 1 = 1
5 x 10= 5 x 10 = 50
1 x 10= 1 x 10 x 10 = 100
15110 = 1 + 50 + 100
151 = 151

Hexadecimal has a base of sixteen (16). The symbols are  0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E and F. Hexadecimal is used to represent binary numbers. F16 = 1111
Every for bits of binary represent one hexadecimal digit.
In our original binary number we now can convert this to hexadecimal.
 100101112
The least significant four bits are:
01112 =
1 x 2= 1 x 1 = 1
1 x 2= 1 x 2 = 2
1 x 2= 1 x 2 x 2 = 4
0 x 2= 0 x 2 x 2 x 2 = 0
0111= 1 + 2 + 4 + 0 = 716
The most significant four bits are:
1001=
1 x 2= 1 x 1 = 1
0 x 2= 0 x 2 = 0
0 x 2= 0 x 2 x 2 = 0
1 x 2= 1 x 2 x 2 x 2 = 8
1001= 1 + 0 + 0 + 8 = 916
Therefore:
 100101112 = 9716 
We can now convert this hexadecimal number back into decimal
9716 =
7 x 16= 7 x 1 = 7
9 x 16= 9 x 16 = 144
9716 = 7 + 144 = 151
The following chart will show all of the combinations for 4 bits (nibble) of binary. Its shows the Binary, Decimal and Hexadecimal (Hex) values. It is interesting to not that Hex is used because you still have only one digit (Place Holder) to represent the nibble of information.

BinaryDecimalHexadecimalBinaryDecimalHexadecimal
00000001000088
00010111001099
0010022101010A
0011033101111B
0100044110012C
0101055110113D
0110066111014E
0111077111115F

ASCII (American Standard Code for Information Interchange)
Two nibbles (8 bits of data) together form a byte. A byte is what computers (PLC) use to store and use individual information. So it will take one unique byte to represent each individual numbers, letters (upper and lower case), punctuation etc. www.AsciiTable.com
Example:
Chr 'A' = 4116 = 010000012
Chr 'a' = 6116 = 011000012
Chr '5' = 3516 = 001101012
Each time you hit a key on your keyboard, the following 8 bits of data get sent.

A word is made up of two bytes, or 4 nibbles, or 16 bits of data. Words are used in the PLC for holding information. The word can also be referred to as an integer.

Long word / Double word is made up of 4 bytes, or 8 nibbles, or 32 bits of data. Long words are used for instructions in the PLC like math. 

Hey what about negative numbers?
So far we have talked about unsigned words. (Positive numbers)
Signed words can hold negative numbers. Bit 15 (most significant bit) of a word is used to determine if the word is negative or not. 
The following table shows you the signed vs unsigned numbers that can be represented in the PLC.
HEX
8000
BFFF
FFFE
FFFF
0000
3FFF
7FFE
7FFF
Signed
-32768
-16385
-0002
-0001
00000
16383
32766
32767
Unsigned
32768
49151
65534
65535
00000
16383
32766
32767
Memory retentiveness:
When working with PLC's look at the memory tables to determine what will happen if power is removed from the device. Will the bits go all off or retain their prior state? 
Usually there will be areas that can be used in the PLC for both conditions.

As you can see PLC numbering systems and computers are very much related and it all boils down to individual bits turning on and off. The interpretation of these bits will determine what the value will be.

Reference: 

Let me know your thoughts, or questions that you have on PLC numbering systems.