PLC5/40 connection to laptop

[gromit 4]

Is there a way to connect to the PLC5/40--(1785–L40B) via a 9-pin standard seial cable from a laptop, or do you need a pcmk card with respective dh+ cable? Please advise.

[OkiePC 14]

IIRC the 5/40 has a 25 pin serial connector and four 3 pin connectors that can be configured for DH+ or RIO. So, with the correct cable, or equivalent, yes you can connect serially, without the DH+ card, unless the serial port is being used for something that would conflict. That port can be configured for RS-232C or RS-422 electrically, and can be configured through software for a user (ASCII) mode. A 1784-CP10 should be the correct cable or you can make your own if you have the tools/hardware. Paul Edited 28 Jul 2008 by OkiePC

[Mickey 71]

Your PLC5/40 has a serial port. ( 25 pin serial) Just get yourself a 9 to 25 pin adapter. Then a null modem cable and connect it to your laptop. Use the RS232 DF1 driver in RSLinx and away you go. Does your laptop have a real serial port? If not a USB to serial adapter will work. Brand "Keyspan is good see link to get one. http://www.plctrainer.net/ Okiepc types faster then I do. Edited 28 Jul 2008 by Mickey

[gromit 4]

Awesome guys!!! I will get the cable and gender changers to establish communication. Will the blank PLC communicate serially in this manner without first establishing some other type of connection whereby the Ch0 serial port can be configured as DF1?

[OkiePC 14]

If, by "blank PLC" you mean in its out of the box condition, then the answer is yes. By default, the serial port will be set up for RS232C. Before you install it in the chassis, verify the dipswitch settings which are used to configure that port. Then, install it, power it up, connect your cable to your PC. Use RSLinx DF1 driver and autoconfigure and it should lock in the baud rate automatically. I think there is a label on the side of the processor, but if you need a manual to verify the dipswitches, go to ab.com and search for publication:1785-UM012D-EN-P

[Guest]

the baud rate for "fresh out of the box" will probably be 2400 ... (autoconfigure should recognize that) ... then once you get online, go to Channel Configuration for Channel 0 and crank the baud up to 19,200 ... you'll lose communications - but then go back to RSLinx and do the autoconfigure trick again ... it should match up again and give you much faster communications ... Edited 28 Jul 2008 by Ron Beaufort

[gromit 4]

Thanks again guys--(Ron, OkiePC, and Mickey)! Your instructions have been very clear and comprehensive. I just retuned from two computer stores, and have not been unable to locate the db25male to db9male gender changer. I will continue looking after work.

[Guest]

or just get a couple of connectors and build your own cable ... then you won't need the adapter ... DB-9-F ------ DB-25-M >-2--------------2-> >-3--------------3-> >-5--------------7-> Edited 28 Jul 2008 by Ron Beaufort

[gromit 4]

Ok, I set up the cable and was able to autoconfigure the df1 driver settings. However, when going online I get the following message, as attached and inserted below. . . . . . "Online Processor is Read Protected! You must Log into a different Access Class to go Online." Any ideas? ProcessorIsReadProtected.bmp

[OkiePC 14]

The processor is protected from having its contents read. Some questions: 1. Do you need the code that already exists in the processor? 2. Does the controller have a working battery installed? 3. Does the controller have an EEPROM module? Paul

[gromit 4]

The controller came from off the shelf in our wharehouse, and is believed to be empty. I installed the battery before powering up the rack. There is no EEPROM installed in the front slot. As you can see from the attachment, the processor appears to be FAULTED. The LEDs are as follows: BATT=off, PROC-solid red, FORCE=off, COMM=green blinking. plcFault.bmp

[Mickey 71]

See Knowledgebase articles for some possible solutions. http://rockwellautomation.custhelp.com/cgi...amp;p_topview=1 http://rockwellautomation.custhelp.com/cgi...amp;p_topview=1 Edited 29 Jul 2008 by Mickey

[Guest]

since you don't care about any existing program, if all else fails you can also try this ... instead of trying to "go online" just use RSLogix5 to start a new "blank" program for your model processor (doesn't have to be exact - just close) ... then do a download of that "blank" program ... note you don't need any rungs or anything - just SOMETHING to convince the processor that it's not completely dead ... then go online with the blank program and continue on from there ...

[gromit 4]

Ron, It looked like it was going to allow me to download a program to the PLC, but then gave me the following error, as inserted and attached. "Download command failed! Do you want to try Log into a different Access Class?" Guys, The culprit was the i/o chassis backplane switch. In particular, switch 8 was set "on", which enables the processor memory protection. I can't believe that I have not run across this issue before. All is working well at this time. Thanks for all of your help!!![/color] DownloadCommandFailed.bmp

[OkiePC 14]

Thank YOU Gromit, for posting the resolution...having (especially positive) closure feels good, and I am sure I am speaking for the other contibutors when I say that. Paul