Ken Moore

The IOM instruction requires three things. 1. Slot: this is the output word address, if your output card was in slot one (16 pt. card), then the value to enter would be: O:1.0 2. mask: this can be used to update only part of the output module, the values should be entered in hex, for example 000Fh, would only update the first 4 outputs. 3. Length, for most 16 point discrete cards this will be 1, Highlight the instruction in your ladder logic and then hit the F1 key, this should bring up the help for that instruction. Give a few more details, and perhaps we can provide a little more help. Hope this helps, Ken

• MicroLogix 1200 and MicroLogix 1500: 100 μs/bit (0.0001 seconds/bit) For example, if bit S:4/7 is monitored in an SLC 500, then that bit will be on for 1.28 seconds and off for 1.28 seconds for a total cycle time of 2.56 seconds. If bit S:4/7 is monitored in a MicroLogix 1500, then that bit will be on for 0.0128 seconds and off for 0.0128 seconds for a total cycle time of 0.0256 seconds.

This guy posted the same question on another board, got lots of answers, but never responded back. I know quite a bit about the 505 pid loops. I asked a few questions to narrow down his problem, but he didn't want to put any effort into his problem. Ken LINK

Not true, Siemens just stopped productin this past June/July, they are still selling what they have in inventory. Control Technologies is picking up production, and plan to be up and running with new controllers sometime in the spring of 2006. You are correct about the 425 though.

I have a project coming up that requires using a CLX plc. Just wondering how steep a learning curve there is transitioning to the CLX platform? I've done a lot of Foxboro DCS programming, so function blocks, timed events, and structured text are not a new concept for me. Can a "skilled" person make the jump without formal training? I just can't spare the time at the moment, and I'm hoping to skip the training for now. BTW, the upcoming project is pretty simple, the only reason we're using a CLX is because of the need for a SIL-2 rated PLC. thanks, Ken

I have a lot of experience with the PLC-5 and SLC/Micrologix platforms, I assumed the move to CLX would not be that big a transition. Just wanted to get a second opinion, before I started something I might not be able to finish. Thanks for all the positive replies. Ken

I'm currently using a Dell Latitude D610 (more mobile than the 810), works nice, and has a serial port, I believe the D810 (has larger display) also comes with a serial port. The price will be in the $1400-2000 range, depending on options. Ken

Using the correct wiring and such, AB remote I/O can be thousands of feet away, it will depend on the baud rate you wish to run at, the faster the baud rate, the less distance allowed. I don't have the specs. in front of me, but I know 4000 ft is doable, and I believe that you can go upto 10,000 feet.

In a PLC-5 system input and output words are assigned based upon the number of configured racks and your addressing scheme (one slot, two slot, half slot), so that if you have an 8 slot rack you have an image table with input and output words for all 8 slots, even if there is only one I/O module installed. But you mentioned RSLogix500, so you must be dealing with the SLC's. In that case Input and output image table is based upon the I/O configuration. As input or output modules are configured the data tables are adjusted to exactly match the configuration. If you have a 10 slot rack with 3 empty slots, there will not be any input or output words for those empty slots. Now to the big question, what exactly are you trying to accomplish? Are you trying to add I/O to an existing system? Have you any experience with the SLC line of PLC's? Guest in correct about using the B and N files for simple bit or data storage. Give us a little more detail, and we will help you as much as we can. Ken

Once you have installed a PDF print engine, you just pick that as your printer and then print your project from RS Logix. The results will be a pdf file of what would normally be a printed document. So....it's not a conversion, it's a printed project file. I have used Acrobat distiller and Primopdf with good results, never tried any thing else, but any pdf print engine should work.

I don't think it exist. Every DCS system I've ever encountered had to be learned from the OEM. They set it up so that, to learn thier system, you have to take thier training. (Which isn't cheap). Some DCS uses have set up thier own user mailing list, etc... to exchange Ideas and fixes. I can steer you to one on the Foxboro I/A DCS if that will help. Ken

Do you have a copy of the 6200 program? If so you shoud be able to open it with RSLogix-5 and then you can make your changes and download to the processor. The following is from the RS-5 help files.

It would be easier to help if you posted your code. Then someone may be able to spot your problem right away.

1. Change the default node address on at least one of the SLC's. I don't remember exactly, but I believe the default node address is 0. Change one SLC to node 1, and the other to Node 2. This is done using channel configuration, then clicking on the Channel-1 system tab. You will also have to ensure that each SLC is set for the same baud rate. 2. Connect the two SLC's using Belden "Blue Hose", you will need a terminating resistor at each end of the blue hose, the baud rate selected in step one will determine the value of the resistor, for example if I remember correctly, 57.6 is 150 ohms. 3. Once the two systems are physically connected. You will have to use the MSG instrcution to pass data between the two systems. I would highly recommend you go to the AB website and download a couple of manuals on the SLC instruction set, and DH+.

Based upon the I/O modules you listed, you only have discrete inputs/outputs. How many of each? What are you trying to control, how complex is it? Based upon the answers to these questions, it might be cheaper to either buy different hardware, or pay someone to do your programming for you. I do not have any experience with the Automation Direct products, but I have been to the website a few times. Since you are a start up, with limited capital, AD may be your best bet. I believe the software is less than $500.00, and the hardware is much cheaper than Allen-Bradley.

Should be pretty easy to do with a 390 second timer, just decrease the setpoint every time the done bit goes true. If timer.dn is true, and setpoint > 35, then setpoint = setpoint-1 Or use a 65 minute (3900 seconds) timer and ten compares. If timer.acc > 0 and <= 390 then setpoint = 45 If timer.acc > 390 and <= 780 then setpoint = 44 If timer.acc > 780 and <= 1170 then setpoint = 43 etc....

Relay output cards: Handles higher amp loads Usually has multiple commons, so one card can handle mixed voltages. Solid state: Longer life, faster response times, cheaper to buy.

Here's a little snippet to get you started. If the pressure is low then the slave will run for three minutes after it is no longer low, then if the pressure goes low and remains low for two minutes, the slave starts. You can change the timer values to fit your needs.

http://store.yahoo.com/surpluscomputers/ms...dos622mswi.html

Heres a link to the Pro-soft modules for the SLC platform: http://www.prosoft-technology.com/content/.../view/full/5629

I think you need a lot more pressure switches, ideal would be about four, or perhaps two with a settable deadband. Let's assume normal air pressure is 110-120 psig. When pressure drops to 105 (pressure switch #1) the 2nd compressor starts and runs until pressure reaches 115 (pressure switch #2). If pressure drops to 100 (pressure switch #3) 3rd compressor starts and runs until pressure reaches 110 (pressure switch #4). Depending on the size of the system, gaining or losing 10 psi in pressure usually takes some time, that would minimize the start/stops of the back up units. You can then rotate the unit functions on some periodic basis, once a day, once a week, once a month etc.... You could also use a pressure transducer with one analog input and several compares.

Unit Status/Overview?

Bill is right, there are several possible sources. What type of PLC are we talking about? Are there other plc's on some type of network with this one?

According to the manual for the expansion card the raw data range is: 0-32760 http://literature.rockwellautomation.com/i...itQueryForm=%BB

Later series ML1200's do support floating point files. When you confirm the project you will get a warning, but it is just that a warning. What series is your unit? The input selection for the expansion module is 0-10V and 4-20 ma, how are you going to connect your battery voltage?