Jump to content

Walkerok

MVP 2015
  • Posts

    261
  • Joined

  • Last visited

  • Days Won

    28

Everything posted by Walkerok

  1. A standard 1N4007 diode will work fine. It is 1000V 1amp. They are very inexpensive. Keith
  2. You can use SB82 the long integer function bit. In the sample lines here this is taking a high and low range of a pressure transducer tomake sure that I can maintain the precision of my calculations for decimal points. In you case you would use the values 4356*2456 = 10698336 which will not fit in an interger but will fit in a long integer using the SB82 bit correctly. Then take this number and divide by whateever number you needed to divide by. At the end divide by say 100 (not 1000) to preserve your final answer as a value equal to XXXX.X which you will be able to show on screen. While this is a patchwork solution that works you should really upgrade to a V130 or better vision model that can just perform floating point math directly and you will like much better. Keith
  3. I see no way to help with your problem unless you post your program. Sorry
  4. Since you do not have a reply yet I will speak up. I have tried to do what you want and I have never been able to get it to work. What I have ended up doing is making the artwork myself and including the text as it should read on the two art pieces I am going to use and importing these custom art pieces into my program. Sorry
  5. To make the three images making up the hand off auto. You will set up an image by pointer and designate an MI for selecting which image you want and an MB for when the image is touched. The only problem with this is how will the PLC know if you were trying to go from off to auto or off to manual? The answer is that if you use the actual three picture image "by pointer" as the touch object you never can know which direction you wanted to go. If you put two buttons under, or above, or wherever to indicate left rotation or right rotation then you can write a simple logic (but it won't look as nice on screeen) so that if you touch the left rotation your switch moves to the left or the right rotation your image will move to the right. Note if you go this way that you need to put the off position as image number one and either the hand or auto as images number zero or two. The logic is as follows: You can make the H-O-A switch only work as described by Michael, but then you will have to cycle through the other positions to get where you want to go. If you chose this method then you will want an activation timer delay so your process does not automatically start as you cycle through either hand or auto to get to off. Personally I believe that this is one of those things where an ald fashioned real 3 position switch is just the easiest way to go. Good Luck Keith
  6. Hi Lawry, You are correct and I feel stupid. There was a second call for the subroutine in the middle of the main routine that I never noticed was there. I took that out ........... and all is right and good with the world again. Thanks for forcing me to turn my head in a different direction. I was so centered on finding a second function I never looked for an extra subroutine call. Thanks Keith
  7. Hi Lawry, Thank you for your response. I know Sb13 exists, but my question is why is SB3 giving a double pulse every one second ( i have already in my ladder to only see the rising edge of SB3)? I will have to try some experimentaiton. Maybe it is because it is in a subroutine, but this should actually have no effect. Also just a note. The ML is used only once.
  8. I have a program in a V570 where I am using SB3 as to increment and ML to keep overall motor run time. I have a very simple net with the only condition being the motor running, the positive edge of SB3 and the increment function block. Every one second my incrementer is counting 2 and not 1 ...... what am I missing? I have compensated by dividing by 72 instead of 36 to make the run time view as 0.00 hours, but I am mystified as to whay I have to do this. Someone please set me strait on this. Thanks Keith
  9. I have a customer that has "sprung" the installation of a pneumatic actuated Fisher V6100 series valve. The valve is a modulating valve to be run from a 4-20ma signal. Here is my problem the valve requires 10Vdc minimum to be able to actuate at all. The Unitronics is not a loop power capable device and does not send out 10VDC untill about 18ma (or so). I am using a V570 with an IO-Ai4-AO2 remote module to try and actuate this (I also have a V200-18-E6B module). Since the PLC is not able to provide what the valve needs. I need a best suggestion on what hardware anyone has used to isolate/amplify an output 4-20ma signal that is capable of providing the r4equired loop power. Any help is welcome Thanks all Keith
  10. Here is a very simple set of program nets to run left and right. This program will rely on the end limit switches making and staying made until the machine starts driving the other direction. The system is also expecting a momentary start button (a maintained button will make this program not work correctly. You have one second delay timers for each direction so the system will run in one direction until a limit switch is made, stop, and one second later go the other direction. Good luck Keith
  11. Looking at you two lines of logic. What you have is not exactly correct. In the first line you are fine with MB17 and Mb18 and your set relay but in your second line you have MB17 being true as the reset. It needs to be MB18 being true as the reset to make this work like a hold circuit. MB17 MB18 ---I I---------------I/I----------(S) MB18 ---I I---------------------------® Or if your physical switches were to be reused where the one is normally open and the other is normally closed you can use the original switches, but the logic needs to change. Lets say you bring your normally open switch into input "I0" on the PLC and the normally closed switch into input "I1" then your logic would be: I0 I1 ---I I---------------I I----------(S) I1 ---I/I---------------------------® Good luck Keith
  12. I have Used M91 controllers and not M90 but generally I would expect that message to mean that the PLC is looking for a remote IO module and is not getting a working data connection between the M90 and the remote module. The would be a loss of commincation at a cable that should be plugged into the PLC's RJ45 expansion port. I have no paperwork on M90 units so I am just guessing here. Keith
  13. If you have a 2 wire sensor you must connect a jumper wire from T3+ to CM for the input to work. If you have a 3 wire sensor the off colr wire will be yout T3- connection and the two wires that are the same color will be your T3+ and CM connections. I have seen this missed several times so I thouht I would mention it. Good luck Keith
  14. I believe that you would be able to tuse the string function "Real Time Clock to ASCII" to do what you want. You can define that your real time clock value is the time you want without Am/PM and then store that ASCII value in your data table. Keith
  15. That is a reasonable work around to increase safety, but from hundreds of miles away on a phone I would definately prefer a difinative fault reason if SB90 is capable of having a defined reason so that when the call comes in I can just say "Oh yes expansion module communication has been lost". But I like the way you think Thanks Keith
  16. Hello all, I wanted to take this topic up again. I am being asked to make a control system where there is going to be a combustible gas monitor. Whenever that monitor reaches the LEL (Lower Explosive Limit) I will have to use the PLC to shutdown all devices in the area that do not have C1D2 or NEMA 7/9 ratings. This is perfectly fine except that if I put any analog devices on an expansion module such as the combustion gas meter it is a potential problem. I understand Emil's response earlier in the chain, but in this case there will relatively un-knowing oil field personel that will simply more than likely just reset the power on the PLC. To their eyes everything will look like everything is fine they will never call to notify anyone of the event and from experience whenever you just reset an expansion analog module the PLC simply holds all of the last values it saw the last time the module was connected and then the oil field personel will leave and the system will have stagnant information that will never move and never change causing incorrect process decisions because of bad data. Im am able to take the steps above to keep the PLC from taking any action, but I would feel much more comfortable if we could at least get a useful explanation of how SB90 works so I can understand the twists and turns of using it in an application where safety is the main concern. Secondarily it sounds like MB90 can be triggered by several things. From a troubleshooting standpoint is the only thing that will fire SB90 durinbg the first scan a lack of connection with the remote IO or if something else can trigger it I need to understand it so I can write a meaningfull users manual for my equipment. In this case I will just put other analog inputs on the remote IO-ATC8 module other than my LEL monitor, but anything I put on the ATC8 will be non functional until someone with appropriate knowladge arrives to do something about it. Thanks Keith
  17. Just a note that may help people thinking about hex and decimal. When you take either form down to the bit level they are exactly the same so even if hex were not avaialble you can represent everything in decimal or visa versa. For example hex 13A = 100111010 (binary) = 330 (decimal) Keith
  18. Is your modem making a connection to the cellular network (solid green light on the enfora). If not you will not be able to connect to the modem to the PLC. Keith
  19. Hi Ben, When set up your configuration block you are setting up 100% of all of the possible phone number you will ever want to text. You have the ability at this point to hard code all of the phone numbers that you want texted, hard code some and make a couple user enterable numbers by using ASCII string entries, or all enterable nummbers (Phone number entries are not done with integers they are done with ASCII because depending on the phone being called or system calling from you my need a pound symbol or asterisk). If your equipment is in the USA then your phone number is just the same way you would dial a phone number for the cell phone brand of SIM card you are using wich is the area code and the number (no dashes or dots). That will allways be true no matter wnat number you will be dialing you just enter number the exact same way you would to dial out witha traditional phone. If you are dialing a number where you would traditionally need a pause like a system that would require a 9 before entering the number you would have your string be a 9(special pause character recognized by the phone system you will be using)area code and number. Keith
  20. I know absolutely nothing about the 4-20 regulator you have so please take this comment keeping this in mind. If your 4-20 device does not provide its own power in the 4-20ma loop then your connections are wrong. You would have to connect the + of your 4-20 to +24VDC and the - of your device to the analog input of the PLC. If the device is self powered then your connections should be correct. Check your hardware setup in your program and that you are looking at the correct MI (or wherever you are storing the analog input data) Keith
  21. Siemens Combustion Center group has 90 degree can bus servos in several sizes including 20Nm, but I do not know if they are an open protocol or a special only to Siemens version of canbus. The general number for their offices in Chicago are (224) 366-8445. Tell them what you want and see if they have anything. Keith
  22. You have 2 ways to do this. 1) Use the float functions 2) Use simple MI values and multiply and divide example A=MI0 B=MI1 C=MI2 Multiply the inside parenthesis by 100 during the calculation Equation changes from C=A*(1+B/100) to C=A*(100+ After the complete calculation for C is made divide the result by 10 to end up with the C value you want with one decimal place. EXAMPLE: 20 pound original weight 35% moisture content (20*(100+35))/10 = 270 = 27.0 on screen value Since you may have entry values to one decimal place it is divide by 10 (if you had on screen entry values to two decimal places don't divide at all to get the C value you want. If you have zero decimal places for your enterable values than divide by 100 to remove the last decimal place just keep in mind you will always be off by whatever the remainder would have been if you have no decimal places). Keith
  23. All you need to do is compare that when you ML is greater than or equal to your desired value "direct store" the constant of the number 0 to the ML. This effectively reset the value to start the process al over again. Keith
×
×
  • Create New...