Spedley

Something like the attatched file??? ... or have I misread you're needs (I've just been told to hurry up!) Pumps.RSS

As Ken says, just save the file when you are online. But if you want to upload (which is no different from saving online) then choose the "use file" option. The comments are stored in the file on the computer and not the PLC. Saving whilst online just copies the program from the PLC and then saves it along with the comments to the file name you specify.

Too late!

Unusual to have (min-max)? I would have done it like this: Output=(Input-InputMin) * (ScaleMax-ScaleMin)/(InputMax-InputMin) + ScaleMin buts thats preference, it boils down to whats min and whats max so ... Output=(Input-10000) * (0-3.125)/(-13652-10000) + 0 Output=(Input-10000) * 3.125/23652 Note: I would not calculate "3.125/23652" and use it as a constant because the number is too small and accuarcy will be lost (this may be your 5% loss), however =(Input-10000) / (23652/3.125) is the same as above and can be reduced to =(Input-10000) / 7568.64 which should be good enough

RS232 is the serial connection and all are the same (more or less). DF1 is a protocol (method of sending data) for communication between two devices. Full duplex means both can talk to each other master to master - which requires a null modem cable - and Half fuplex is more of a master slave scenario. ASCII serial communications is different, the serial cable defines haw data is transmitted, ASCII is the set of characters that is sent and DF1 says what the characters mean. I don't know what SB1 is but I doubt it is compatable with DF1, however if both machines can use ASCII then you can send simple message that way. ... I think, its something like that anyway.

Am I right in thinking you want to start a program from scrath on the same machine? If so, I would do an ASCII export on the Database (just the EAS file). Select delete DB and then Click yes, add default descriptions. Delete all the program files and data tables. Open the EAS file with Notepad and delete all the lines which are not I/O, resave it and ASCI import it. It would be nice to have a quicker way but it only takes 5 minutes at most and it's not something you do every day.

I have spent many hours learning to use Allen Bradleys SLC503 ASCII istructions. Here are a few pointers I have learned to keep things simple. 1. Only ever use one Read instruction and one Write instruction. 2. Use AWA instead of AWT. AWA adds the characters in the Channel Configuration to the end of the message. 3. Use ARL instead of ARD. ARL reads characters until it reaches the Termination Characters defined in Channel Configuration. i.e. it reads the whole message not a set number of characters. You must set the devices communicating with your MicroLogix to append the same end of line characters to their message. 4. When an ARL instruction is enabled it will stay active until it reads a line. If the rung goes false, the ARL instruction will still continue until it reads a line. 5. This bit can be very confusing ... When ARL reads a line the DN bit will come on, however if there was a message waiting to be read then the DN bit will just stay on from last time. The DN bit only goes off if the instruction has to wait for a message. The EM bit can be used instead - this bit comes on the next time the instruction is scanned but be carefull with it. I suggest you spend a few hours understanding how the ASCII instructipon and queue work. 6. Because the ARL reads a whole message, you can use ASR to compare it with a string to see if its a match or use multiple ASR instruction to test for which message has been read. Put the opperands in the correct order and the comment will show for the test message. 7. Error detection can be very tricky and I suggest should any message be unknown you stop the machine, reset the buffers and control registers and get an opperator. This never really happens so I wouldn't worry about it. 8. Be aware of the buffer i.e. if a machine has been cycled manually the messages may still be sent to the PLC and sit in the buffer waiting. When you start the machine and send SENSOR_1 a reply from the last part may already be in the buffer. WATCH OUT! Some of these may require a little getting your head around (and its a while since I changed any ASCII code) but unless you do you will get stuck.

If the belt is stopped, the only method of detecting it is waiting for soemthing to happen (which wont) but as you say this could be 30seconds. The other option I would explore is measuring the current the drive motor draws, if the belt stops it should increase significantly for no reason.

You know what ... you're quite right, I hadn't actually thought about that until now but I have seen that behaviour. ... so using SOR OSR B3/1 OTE B3/0 EOR then B3/0 is actually a "first scan" bit (I think I used this many years ago when I was learning)

Is this deliberate behaviour or a bug?

As far as I'm aware all data memory in the SLC500 range is retentive.

Unfortunatly I'm only familiar with RSLogix500 but (U) means unlatch the bit only if the rung is true and (L) means turn the bit on only if the rung true - as opposed to ( ) which would set the bit to the state of the rung. MCR is as you say all the rungs between MCR instructions evaluate to false if the MCR evaluates as false.

There is nothing that I know of to cause that.

If the Properties tab of say, a message display is set to single bit and the Data Type for the tag is set to something other than a single bit then putting '/' in the Tag address gives this error. This is the only way I can think that you may be having problems. For clarification If the Properties Tabs is set to single bit the Tags Data Type should be data bit and the Tag Address should include '/' (and the opposite) If you say what the object is and exactly what these options are then you will probably get better answers.

I just read your other thread on the same topic. I don't know but it may make a difference if you put 1000 into an N-file and use that for the division. What are you using as the destination for the DIV instruction? It should not be S:14 You say it sometimes works. What do you mean?

I think after a division, the resgister S14 is the non-rounded integer part and S:13 is the remainder (modulous) or maybe its the otherway around.

If I want to display a large amount of data on one screen (grid of words 8/10 + Pushbuttons) what is the best setting for the Update Frequency so that the screen is as responsive as possible? Any other tips? (PV600 & PV550)

If I remember rightly Statment List is just assembly language geared towards ladder logic? A bit like this ... SOR  XIC B3:0/0  BST    XIC B3:0/1   NXB    XIO B3:0/2  BND  OTE B3:0/3 EOR etc... You could just type this into a rung as SOR XIC B3:0/0 BST XIC B3:0/1 NXB XIO B3:0/2 BND OTE B3:0/3 EOR and it displays it as ladder logic which in my eyes is far easier to read. The only reason I can see for wanting statment list is its a lot faster to write code compared with using drag and drop with the mouse. I find it a much better system with RSLogix.

Are there any differences between Bit Files and Integer Files other than the way RSLogix displays the information?

Just a little side-track. If using the 1747-UIC to connect to the DH485 port (e.g SLC5/03 and PanelViews) then what type of cable do you use? P.S. my first post so hello everyone!