MrPLC Member
  • Content count

  • Joined

  • Last visited

Community Reputation

1 Neutral

1 Follower

About neildobson

  • Rank

Contact Methods

  • Website URL
  • ICQ 0

Profile Information

  • Location The North
  • Country United Kingdom

Recent Profile Visitors

1117 profile views
  1. Free Siemens Programming Software

    For those getting started in PLC programming, perhaps you might be interested to hear Siemens are giving away some software. Link
  2. AC vs. DC for control

    We pretty much standardise on 24VDC for all but the largest of systems. The main reasons include: We use lots of PLCs, most of which have 24V inputs. Ease of which to interface with hardware such as variable-speed drives, sensors, small solenoid valves, LEDs, and other electrical/electronic devices, most of which again standardise on 24V. From a safety point of view - a requirement to keep voltage levels below 50V. Relatively low cost of DC power supplies nowadays. The only reason we would use AC for control would be when dealing with higher current devices where the cost of contactors and other control gear becomes expensive. In this case we use a mix of AC for control and DC for I/O devices.
  3. Panel Labels

    Not sure what type of labels you're looking for but we've just invested in a printer from partex. This machine does most things from wire markers to component labeling, cable identifications etc. The machine uses various tapes, tubes, heatshrinks etc. for loads of marking tasks. The only thing it doesn't do is label plates for the panel doors. For this we use a local signmaker. Hope this helps.
  4. DH+ Connectivity options

    We have been asked to carry out some code modifications to a network of 5/04 processors and panelview terminals all connected on a single DH+ segment. I would have been happy to connect to each device using the CPU's RS232 port using a CP3 cable, however some CPUs are doing point-to-point comms with other devices such as servo drives, and I have been unable to establish a link with them using RSLinx. I thought that there might be a way to tunnel through one CPU via its serial port and gain access to another CPU on the same network over DH+. However this does not seem to work for me and the processors that I can actually connect to show up as the only available devices in Linx. My question is what is the most economical way of connecting to any CPU and panelview terminal over DH+ network using a laptop PC? Thanks for your help.
  5. We are quoting for a control panel upgrade which will contain a CompactLogix PLC (1769-L32E) which connects to a Red Lion G310 operator interface via ethernet. This interface offers a web server capability which we intend to use to remotely monitor machine status and for debugging. We would also like to gain access to the PLC remotely. I was wondering if anyone has experience with Red Lion operator interfaces connecting to AB equipment over ethernet? To be able to access the web server and the PLC must I set-up port forwarding and open ports to connect over the internet? Any advice would be appreciated. Regards,
  6. Fx1/2/3 Programming Port

    I've tried changing the baud rate of the e-terminal but I don't think this works as the FX prog port defaults to 9.6k. In any case as Sergei suggested, perhaps the baud rate should be left as default in case anyone connects to the PLC in future. I just wanted to increase speed so that the terminal would update a bit quicker if I intended to display lots of live variables and perhaps scroll some messages etc.
  7. Fx1/2/3 Programming Port

    Does anyone know how to change the baud rate of the FX programming port? I have the new FX3U CPU and would like to connect a peripheral device (E-series terminal) directly to the programming port and take advantage of the higher baud rate offered. I've noticed in GX Developer the software connects to the CPU at 112K without any adjustment. However when I connect the E-terminal it only works at 9.6K. I guess GXDEV changes the baud rate temporarily whilst downloading/monitoring etc? I've read some of the new FX3U communications manual and it doesn't mention anything about connecting directly to the programming port and I don't believe setting D8120 has any effect on the prog port but i'm not really sure. Help as usual would be appreciated. Thanks.
  8. MAC E200 to QJ71C24N-R2

    Thankyou, after studying the manuals and a bit of experimentation i've got it working. Here are the settings for future reference: E200 terminal configured with default C24 protocol settings: - RS232, 19200, N, 8, 1 C24 module settings: -Baud rate:19,200 = 07H (bits 8-15) -bit 0:OFF - independent -bit 1:ON - 8 data bit -bit 2:OFF - no parity -bit 3:OFF - odd parity (ignored) -bit 4:OFF - 1 stop bit -bit 5:ON - sum check on -bit 6:ON - write during run enabled -bit 7:OFF - setting modification prohibited Setting = 62H Protocol Setting: -Format 5 = 05H Configuration in GX Developer: From PLC Parameters, I/O assignment, Switch setting, enter the following for the communications module: Switch 1:0762 Switch 2:0005 Job done.
  9. MAC E200 to QJ71C24N-R2

    Can anyone help me with comm settings to enable me to connect an E200 to the Q-series RS232 module? I had the terminal working for a while but after fiddling with the baud rate I can no longer get any comms. I need to reduce the baud rate to 19200 because of the 20m long cable length. I see there is a switch settings dialog in GXDEV I/O configuration but when I adjust parameters here it seems to affect my programming port connection. Do I select the CPU protocol or C24 protocol in the E-terminal software? Any have example switch settings? Any help would be most appreciated.
  10. GXDEV PLC Transfer

    I've been using GX Developer for a couple of years now and there are a few things that annoy me a little like the non-use of modern windows dialogs (instead of the circa 1990s dialogs for open, save etc.) but the biggest annoyance is with transfer settings. We use lots of FX PLCs and unfortunately we don't have time to sit and test applications on paper so we have to constantly modify the program, download, test, modify, download, test etc. etc. When downloading you first have to select the MAIN program by clicking the checkbox and then press execute button. This of course will download the program to the PLC writing the whole of it's memory. If you are constantly downloading new revisions you can save a bit of time by just downloading only the memory used by your program. For instance if your program is 156 steps (goto the last rung and note the step number) you can select the Program tab and pick Step Range and enter the step number. The problem is GX Developer doesn't remember any of this meaning you have to go through the same steps each time you download. I can't seem to find a way of persuading the software to remember my settings. Any ideas? What would be cool is if GXDev defaulted to select MAIN program and there was an option in the program tab to download 'just the program'. This would save a whole load of time in our developement. I don't know any way of getting feedback to Mitsubishi on matters such as this...I'm from the UK!!
  11. Remote I/O problems

    I have a strange problem where the remote I/O is freezing (the inputs change state but the image table is not updated in CPU). My application is quite complex. I have four main racks populated with a variety of digital and analog I/O. This is expanded by using the D4-450CPU as remote I/O master (the 25-pin port) which connects to an additional two remote slave racks also containing various digital I/O modules. Finally for good measure the main rack contains an H4-ECOM ethernet module which connects to a PC which does logging/data capture functions. This application has been running quite successfully for the past 7 years. However from day one we have had some mysterious I/O problems where certain ladder rungs do not operate correctly. I have spent some time on this recently and the problem is the remote I/O. One of these racks has its inputs and outputs configured as X1000 and Y1000 respectively. So the following example should work fine: ----[X1000]----------------(Y1000) You would naturally expect when bit 0 of remote inputs turns on (X1000), the first remote output bit 0 (Y1000) would also turn on. This does work. However after a while, the I/O is no longer updated and if Y1000 is already ON, then if we lose X1000, Y1000 still stays ON. Conversely, if Y1000 is OFF (because X1000 is off), then no matter if X1000 switches ON, Y1000 stays OFF. The problem appears to be that the CPU forgets to refresh the I/O image table from the remote I/O racks and the whole lot is just frozen. Even more strange is that to fix the problem we fire up DirectSoft and as soon as the link appears (green icon) in the launch window, everything fires up normally and I/O refreshes fine for a while. I guess there is no easy answer for this, but I have a number of things to look at: 1) The remote I/O cable. This appears to be wired correctly and is only 5metres end-end, fitted with terminating resistors. I will check screening, resistor values etc. 2) Remote I/O configuration. This has been checked over and over and as far as I can tell this is correct. The I/O is configured as per the example in the D4 user manual. The unused slots are zeroed and C740 is set. Everything is set-up using first-scan bit SP0. Is the remote I/O information in the D4 manual correct? I see it differs slightly from the remote I/O manual. 3) Remote I/O status. I have seen no errors on any of the slave racks. Perhaps the status bits should be logged? 4) D4-450 as remote I/O master. How reliable is this. Any problems reported? Would it be better to use a D4-RM instead? 5) H4-ECOM. There is some heavy duty logging going on. Could this cause issues in the CPU? If anyone has had any remote I/O problems, particularly if using the D4-450 as remote master, or had any other problems when using the H4-ECOM I would be interested to hear from them. Regards,
  12. FX40DU-TKES

    My customer has one of these connected to an old FX PLC and wishes for us to carry out some mods to it. However I am unsure as to which software and programming cable is needed. Can anyone help? Many thanks.
  13. Q40CBL-3M Cable

    Anyone used this cable before? I need one to connect to an encoder to the Q173PX module. This module has a 40-pin connector (similar to other high-density modules). Normally an A6CON1 is used, but of course you'd have to solder a cable. The Q40CBL-3M is (apparently) a ready-made 3M cable but I can't seem to find details of the cable colours (or is it colors . I've done a search on all my PDF's and on google etc. Is this a Mitsubishi part? I will receive my cable in the next week or so, but I just wanted to get a schematic drawing done in advance.
  14. GX IEC Developer

    We're designing a machine with a Q-series PLC with a CPU172N motion controller. It has been suggested by Mitsubishi that we consider using IEC developer instead of GX Developer (which we have). I've not looked at this software yet but I hear it has been developed in Europe and is quite different to standard GX Developer. Does anyone have any good (or bad) things to say about this software? Those with IEC Developer, do you use it exclusively for all Mitsi projects (even small FX applications) ? What about the (so-called) overhead, does this affect scan-time much? Does IEC Developer have ability to convert projects to/from GX Dev? What is the latest version and is there a demo available? Thanks in advance for info.
  15. MC Protocol VB Sample Code

    I found this document which explains a bit more about FX CPU (Programming) Protocol. This is quite interesting as it implies that you can do single bit read/writes as well as words. However I am still unsure what are the addresses of all the PLC devices. This protocol does not use D,X,Y etc. Anyone shed any light on this? mitsufxs.doc