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Volume 1, Issue 7APPLICATION ARTICLE Check out how one of our customers takes full advantage of the analog capabilities of the Smart-PAK PLUS more > If you have an application that you would like to submit for consideration, email us at plcs@entertron.com and in the subject area type in "application article" TECH TIPS What do you do when you have analog signals that fluctuate due to noise? In the analog world there are many sources of noise that can cause the analog to fluctuate. One of the best ways to smooth out the analog channel is by taking an average of the analog input over a certain period of time. There are two ways to do averaging inside the PLC ladder program. You can write a program to record the values to individual registers then add them up and divide by the number of samples you have taken. This is not the most efficient way to do averaging. It wastes program space and registers. The second way to do the averaging is to add the analog value a certain number of times to a register and then divide by the number of samples you have added. You must be careful not to go over the 16 bit register maximum value (65,535). To determine the maximum number of samples you can have in one register, take the maximum register value (65,535) and divide it by the maximum analog value (12bit = 4095) In this case sixteen times (65,535/4095=16.003 use the whole number value) Below is an example program that you can use as a guide to accomplish this averaging. If there are any questions you would like answered, email us at plcs@entertron.com and in the subject area type "tech tips question" THE PROGRAMMERS CORNER Pack/Unpack The pack and unpack instructions are very useful commands, especially when looking to store the status of internal relay bits or to convert a binary number to the decimal equivalent. Pack The pack command takes a series of internal relay bits ands packs the decimal equivalent into the accumulator to be worked with. The value can then be operated on or placed into a register for storage. Unpack The unpack command takes a value from the accumulator , then unpacks it to a series of relays. The relays can then be used to perform a certain function. (Whatever is currently in the accumulator, can be a TC register as long as you use the get command to get the TC register value into the accumulator) This command is commonly used to save and restore setup parameters. It can be used in conjunction with a touch screen to save/load hundreds of different configurations. Eware32 Tips and tricks Entertron provides off-line simulation of the ladder logic program through E-Ware32. The simulator looks similar to the on line monitor feature, but allows you to debug your program without having to download your program to test it. You must save and compile your ladder logic program before you can use the off line simulator. To begin simulating, go to the menu bar, under view, select "simulator". This will put you in to simulation mode. Note - You can not edit your program in simulation mode. Working with the Simulator From the menu bar, go to "tools", select "simulator", then "options" From here you are determining the number of scans and the scan rate (in ms) Then, go back to "tools", select "inputs" . From here, you can choose the specific inputs you want either on or off for your simulation. This can be done and changed throughout the simulation process. You have two choices in "simulator" as to how many times the simulator scans. There is one scan and "Scan N". Scan N allows you to choose the number of scans you wish to simulate. Scan once will only perform one scan (Each press of the space bar will also perform one scan) The simulator simulates basic logic in the PLC, You cannot simulate the following: A - Serial port functions B - Analog inputs (analog outputs are values written to a register. These can be simulated) C - Activation of an internal relay (Usually done with an operator interface for control) If there are any questions you would like answered, email us at plcs@entertron.com and in the subject area type "programmer's corner question" THE ENTERTRON ADVANTAGE This issue's Entertron Advantage deals with two programs that truly differentiate Entertron from all the other manufacturers of PLCs today.
Our Introductory Offer Other PLC manufacturers tend to offer a few different options as part of their approach to get you to buy a unit to evaluate for your application. Ask yourself this, how often do the packages they offer actually meet your I/O requirements. Many of the offers I have seen are basic packages that include the programming software, cables and one of their basic configurations (usually a micro). We at Entertron consider this approach to be, for lack of another word, useless. Why purchase an introductory package when it doesn't meet your application requirements? Your first order should be able to meet your requirements, not just simply get you the software and a PLC that you will not be able to use. Entertron has developed an program for all first time OEMs. Your first order for the controller of your choice, that meets your application requirements, computer cable and Eware32 programming software is 50% off our 1 pc OEM price. You can order up to 5 controllers with our introductory offer. This offer is only available through our news letter. Mention where you saw this offer to us when ordering for the first time and you will receive our introductory offer. Our Warranty A typical warranty from other PLC manufacturers is one year. What happens when the warranty expires? Some manufacturers repair their own products, while others don't and you are therefore reliant on third party repair houses. At Entertron, our ePLC warranty starts at 5 years (Smart-PAK series and SK1600-RIC), stating that our products are free of defect, from normal operation. The Elite-2000 is warranted for 7 years. No where in our industry will you find anything that even comes close. So, your ePLC is covered for 5 years...what happens after that? At Entertron, we give you a total of 10 years of service for the controller you purchased. After the controller is no longer covered by warranty, we will repair our controllers for up to a total of 10 years (warranty + additional years = 10 years). So if you have a Smart-PAK PLUS, we will support that controller for the 5 year warranty plus an additional 5 years. After the warranty has expired, what costs can I expect to pay? After the warranty has expired, there is an evaluation fee that is charged. This fee covers the cost of an Entertron technician evaluating your controller to determine if there is a problem, and what the problem is. If there is nothing wrong with the controller, you will only pay the evaluation fee (plus shipping costs). If there is a problem with the controller, you will be assessed a total cost for repair. Why don't you repair controllers that are over 10 years old? We consider 10 years to be a very good return on your original investment for one of our controllers. The probability that additional problems will occur on controllers that are over 10 years old is much greater, than on a new controller. We don't want our customers repairing the same controller more than once...the adage is "throwing good money after bad". Keep in mind that 10 years is not the limit for our controllers. We have customers where our products have never been replaced or repaired for over 20 years of operation. PRODUCT NEWS With today's PLCs, they tend to lack the ability to store data from the results they generate. As a result we have recently introduced a product to address this issue. LoggeR is a serial data logger designed to store up to 16K worth of data in various formats. There is really no product on the market like it at this point. Most data loggers are either analog based (requiring analog signals from the PLC) or they are just out of the price range for a low cost PLC. LoggeR comes with our PLC interface cable and a software utility program that enables you to "dump" the stored data into an excel spreadsheet. The cost for all of this starts @ $195.00 (complete). Also available for review is our press release on LoggeR SPECIAL OFFERS This Newsletter Special is available to any OEM that has never purchased from Entertron in the past can take advantage of this offer - 50% off any controller, in any configuration. For more information, click for details. When speaking and or emailing your request to Entertron, you must mention that you saw the information in our newsletter. To the many students that are currently learning about the incredible world of PLCs and programming, we are offering you a special student discount - Any controller, any configuration - 20% off (includes computer cable and programming software). Compare this to other offers and you will see the benefits. CLOSING NOTES Stay on the lookout for our new upcoming total solution - "The Power of "e" that centers around Entertron's ePLCs. We have been continually updating our home page to provide you the customer with as much information as possible, without making it too imposing. Our goal is to provide you with easy access to many areas of our web site without having to hunt for the information. Please keep an eye on our site, because information is continually being added. If you have missed an issue of Entertron Intelligence, not to fear, you can view past issues on our web site. Any general questions, not related to one of our subjects can be emailed to us at plcs@entertron.com and in the subject area type in "entertron intelligence question" If you decide that you do not want to receive our monthly newsletter, email us at plcs@entertron.com and in the subject area type "please remove from list" and we will honor your request. |
