Joe Tauser

Have you written the code for one input yet? Can you post it? Joe T.

I set up a very basic configuration with an -E3XB module and downloaded it, with the frequency mapped to ML 0. I had no trouble entering 50,000. I did configure the display variable for six digits, which is not the default. Take a look. What exactly is the load you are connecting to the module? Unitronics has a connection diagram on page 5 of the V200-18-E3XB specification sheet, but if you let me know what you are hooking up I can draw a more detailed schematic. Joe T. V570 ML PWM test.vlp

You guys have really got my thinking about this virtual machine stuff- I've been using XP only for so long that I haven't had to try it yet. I did enjoy reading Tim's blog on Linux Mint. I'm going to try setting up a Win98SE virtual machine so I can dig out my old copy of "Redneck Rampage" and play it on the Mancave computer. Joe T.

The thought of 3,450 lines of code makes my head hurt- really bad. Is there a reason why you can't use indirect addressing in this application? Is the response time very critical? Joe T.

Setting up an -E3XB for PWM is pretty simple and it sounds like you've done it right. When you enter 20,000 in the frequency MI, what frequency do you actually get? Are you measuring it with a frequency counter or an oscilloscope? What type of load is connected to it? Have you tried measuring the frequency at 50% duty cycle? If you're trying to measure the frequency with a frequency counter instrument, you may be running into problems with the harmonics of the square wave output. You can also assign an ML to the frequency on a PWM output, and in NPN mode it should go to 50 kHz. Joe T.

Alex is exactly right- we need the specs to your fan to be more helpful. Just as a guess, I dug around for the specs on an 80 mm 12V computer fan. These draw about 170 mA, so there's no way you're going to connect something like this to an analog output if that's what you were hoping to do. The M90 you're using has PNP outputs that are usually powered by 24V, but you may be able to power them with another voltage that matches the fan. This is a question for the creators. A PWM program for the M90 would not be complicated. Instead of thinking in terms of control voltage, you will actually be quickly pulsing the fan with current which will work just as well. The feasibility of your hardware design needs to be resolved first. Have you asked your distributor for help? Joe T. Later in the evening.... I wanted to test my theory that it wouldn't be a complicated program so I put some code together. This would work in an M90 or a Jazz with transistor outputs. Of course the easiest way to get PWM is buy one of the units that has an HSO output. M90 PWM.U90

How many amps do you want to control, what is the type of load, and how much money do you want to spend? If the load is resistive and you're willing to spend a few bucks then these will work: Analog SSR A 25 amp unit is about $100.00 Joe T.

How exactly are you going to step the voltage and what are the steps? Have you determined in what voltage range the fan is effective (if you spin it too slowly, it will do nothing). What you probably need to do is create a crude PWM (pulse width modulation) setup. The M90 does not have this function like the Vision series does, but you could make one. If you don't know what PWM is then do a little research on the Internet. It will give you some insight as to what your program needs to do. Joe T.

This sounds like a hardware problem. Do you have another V570 to try? Joe T.

Ted, Welcome to the pack! I am a distributor in St. Louis - feel free to call me anytime at (314)878-9910. I've had the line for 10 years and I've programmed most of the PLC's out there. You'll find the forum to be an excellent resource with several non-paid moderators such as myself that bring a lot of real-world experience to the table. I'll try to answer your questions in my usual heavily-opinionated manner: Yes, it is very awesome considering the price. It's one of the main selling features of our product. You can almost always (99%) open an old program in a newer version of the software but it will ALWAYS require an update of the various OS files in the flash ROM of the PLC. You'll have fun learning about this. Short answer- no. The HMI is not linked to the ladder editor in any way. You could draw and animate pictures of the logic on the HMI screens if you really want some practice with the screen editor, but this would be a pain in the butt. Go back to answer (1)- free software and give copies of the program to those who need to view it. Threaten bodily harm and/or immediate termination to un-authorized edits. Or keep the code to yourself if you have a problem child who likes to play and doesn't listen. Dive into the Help and read all about System Bits and System Integers. These are very useful bits and registers that you can access from your logic and HMI variables. You're only limited by your imagination here. Digital I/O are updated every scan, and I/O on the main board can be updated faster using Interrupt Routines (again, read the Help here). Analog I/O have a response time of about 25 ms. I may be a little off here- if it's really important then send a question about it to support@unitronics.com. If they don't get back to you right away then send an email to Emil- he's really the expert on this. Good luck in your Unitronics adventures. Post any more questions you have and keep us up on your success! Joe T. PS - Don't hold your breath for a simulator. It's been the most requested item for years and they know we want it, but Unitronics has only so many developers and they spend most of their time working on new products and adding new functions to the software. I've found the best thing to do is buy some extra PLC's and put them in demo stock for your own use. They're not that expensive in the big scheme of things.

For a request like that, I wouldn't even bother using a timer and all the needed conversion blocks. I'd make my own with SB 13, an INC block, and a GEQ block. Then you can give the customer whatever he wants. Unfortunately, standard functions do not meet 100% of all imagined control schemes. Joe T.

Do an Internet search for "Modbus I/O". There's a ton of stuff out there. You'll need to add a Modbus polling routine to your program to read them, but that's not too terribly difficult. Joe T.

Use two MI's - one to track the count to 1,000 and then increment a second one and reset the first. Example: MI 1 will contain the thousands and MI 0 will contain the value less than 1000. You can create two variables and put them next to each other on the Jazz display. Joe T.

Very thorough, Nacho! You listed several commands I was not aware of! Joe T.

Here's a program with the SMS table configured. I don't have the hardware here right now to test it. MB 1 triggers the send. MB 2 "should" come on when it receives the reply. You'll want the read the Help on Com Port->Jazz series to use special function 310 to get the port parameters the way you want them. You'll also want to read all the SMS Help topics. I learned many moons ago that SMS allows us to control the com port - just leave the "Use GSM Modem" unchecked. This program automatically converts the incoming stream to a number. This may or may not work for what you're trying to do. Good luck. Let me know if I need to bring some hardware home to bang on it some more. Joe T. SunXComm.U90

Damian, Post a sample of the string this thing spits out. Joe T.

Don't know for sure, but I was able to configure the SMS Message List and insert a variable and it didn't barf. I'm guessing yes. Joe T.

It's a bit convoluted, but I would suggest building your MMDDhhmm number in an ML and then doing a NUM to ASCII on it. SI 32 contains DDMM, so the first thing to do is divide it by 100 to knock it to DD only. The remainder MM will be in SL 4, so you can multiply it by 100 and add it back resulting in MMDD. Next multiply this by 10,000 and put it in an ML to get MMDD0000. Add SI 31 HHMM to this ML to get MMDDHHMM. Now when you run it through the NUM to ASCII block with length 8 you should get your string in four consecutive MIs. Joe T.

The best you can do is an approximation. Break your error into segments and create a data table in the PLC that has the average error for a given temperature range. Then use compare blocks on the reported temperature from the IO module to determine what range you're in, look up the error, and add or subtract it to create a corrected temperature value. Joe T.

Just guessing, but you may need to upgrade your EX-A1 to an EX-A2X. I don't know how well the IO-16A3's play with the older module - the creators will have to shed some light on this. Joe T.

It is very possible that the contacts of the PLC's relay have become pitted and intermittent, especially if you have an inductive load such as a solenoid connected without an RC snubber across it to absorb the electrical spike that is created when the solenoid is released. If you have a spare output try changing your program to use it and move the wire to the solenoid. Joe T.

Using a terminal program is the best way to troubleshoot any problem with serial communications. This is the one I like best: Bray's Terminal This program allows you to view the strings in ASCII or hex, which can be very helpful in discovering checksum or terminator characters. Many moons ago I was troubleshooting a problem with US Robotics Sportster modems and discovered that they added error check characters to the end of the string which will totally choke Unitronics communications. Hyperterminal doesn't give you this kind of information. Glad you were able to troubleshoot your problem. Steel is forged through fire. Joe T.

Oh.. Cara... be careful what you post about your past on the forum. This just screams for one of my photo-shopping projects . AZ - the front of the V570 will be fine in a corrosive environment as long as you use the gasket. I'd be more worried about getting cow poop all over the touchscreen. If this may be a problem, then you want to look at the V560 which has both a touchscreen and a full keypad with function keys. You build your screens so that the most of the common operations such as screen changing and data entry are tied to the function buttons. Joe T.

Cara- There is no Help topic for "Toggle Bit in Vector" function under the Vector menu. In your copious free time Joe T.

A V570 is a good choice for a system this size, as it offers a local 5.7" color touchscreen and has a built-in CANbus port which you will probably need for the number of I/O you have. You can also look at the V1040 or the V1210 if you want a larger screen. You can use the second COM port to set it up as a Modbus slave for an external HMI. Joe T.