I keep toasting TTL-RS232 HMI program cables any help why

I have a few quickpanels on some older equipment. Connected to GE Fanuc 90-30 PLCs.
I have went through 4 of the MI-CAB-C49 cables over the past few years. Im wondering why. It seems every time I go to use it the cable is toast again. I am the only user that uses them.
I power off the HMI before connected or disconnecting(im not 100% sure on the disconnect, but will from not on)
When call for a download, it sees the comm port, and tells the screen to go dark. Then prompts me to remove power from the HMI. Then after I do that it immediately tells me to power it back up. Then when power is applied it says waiting to go online. It times out and starts this again, asking me to power it off.......
I have seen this previously, and a new cable has fixed the issue. What could i be doing that is causing this problem?
Any foresight is appreciated.

I would check your grounding. Ensure that the grounding terminals of the PLC and HMI are the same.

Hope this helps.

Regards,

Are you using a USB/serial adapter or a real COM port? I've never had a problem with a COM port. The laptop I use that has Quick Designer on it has a COM port so I've never had to use an adapter. The electronics in the cable is powered from the QP side.

I will check and address grounding issues.

I am using a Allen Bradley 9300-USBS USB to Serial adapter. It has worked on everything I have thrown at it.

I wonder is there a way to insure the laptop is grounded to the machine before I plug it in? Just the charger doesn't seem like it would make a good ground. Any suggestions, or maybe im barking up the proverbial wrong tree.

IIRC there were issues with these 'dying' pre-version "J"
Forget the HMI-CAB-C49 cable and get one of these:
http://www.plccable.com/ge-quickpan...pb-hmi-cable-proface-usb-gpw-cb03-a-gpw-cb02/

No guarantee by me but I have used this on QuickPanel version QPx2 and QPx3 with both QuickDesigner on Virtual Windows XP and Proficy ME on Host Windows 7 without issues.

Although in a 'noisy' environment using QuickDesigner you may still need to manually drop the baud rate from the default by editing the courier.ini file.

New development. My new cable does the same thing. I really have no way to verify if the cable is the culprit, but I suspect it is not.
I'm on a workbench with a quickpanel, and getting same results.

When I ask it to download the display goes blank, then a few seconds later the quick courier software asked to power off the display. As soon as I do this it asked me to power it back on. 15-20 seconds later it says "display is not responding", and to power it off again. the cycle continues.
Any suggestions?

My suggestions.
~ If you have another HMI-CAB-C49 and as you are using QuickDesigner get rid of any USB to Serial adapter and try a real serial port.
~ Drop the initial baud down to 9600 or even 2400 in the courier.ini file.

I hope that you have the program on a computer already as a backup. If only in QuickDesigner 'Export' it to a .prj file for archiving.

Thanks for the suggestions RussB, but still not resolved.

This is in the help troubleshooting on the Quickdesigner software.
Under section 2. "Turn the Unit Off"
2) During the download, the QuickCourier message box says, “Determining display device...”. Then after some time the software asks you to “Turn the Unit Off..” Then after turning unit back on, the compiler goes on to ask you to “Turn the unit off” again, then on again, then off again, etc.

a) Check the cable that is being used for downloading. The cable should be HMI-CAB-C49. YES. I have 2 cables both same thing.

b) Check the Com port that is being used. Make sure that it is not being used by some other software package. Also check the comm. port’s IRQ (interrupt) settings. Some other installed device may be using that comm. port’s setting (Com 1 IRQ = 4 and Com 2 IRQ = 3). This can be done under the Windows Control Panel then select Ports. How do you find IRQ on a USB serial adapter. I also have miniPCI serial adapter im using with same issues.

c) The HMI-CAB-C49 download cable may be damaged. Try another download cable to see if the download will continue. Tried 2 different cables.

d) Make sure that the incoming power to the QuickPanel unit is sufficient. This is usually an issue with the 24 VDC unit. Funny thing here. I have 2 different models here. QPI-211XXX and a QPJ-2DXXX. I can program the QPJ, but not the QPI models. QPJ is 24v the other is 120v.

e) Exit out of the download then exit out of QuickDesigner software. Go to Windows Notepad then open the file Courier.ini that is found in the directory where QuickDesigner was loaded (usually c:\quick?). Change the Autobaud from the 38400 default to 9600.
I have tried as RussB suggested and went to 2400 with the same results.

I do not have serial ports on anything that I can load the software on. I am using the USB9300, and have tried a generic PCIE serial card. Both giving the same results.

I have reinstalled the quickdesign software. Exported, and imported the PRJ files. I created a new file with just a text screen to attemp to download, with no luck.

You can destroy TTL chips by putting 5 volts on signal pins, but no power on it's supply pins. Causes back-circuits inside IC. So, if that's what's happening here, then how?

I tried to find schematics. Is the MAX232 getting powered from the HMI? That's the only way I could see this happening. I suspect with power off, voltage on the signal pins from the USB-RS232 adapter is powering the MAX232 via it's input pins.

Try this: Disconnect the cable prior to powering off the HMI. If that does it, then the next thing is to find a USB-RS232 adapter that doesn't blow up the cable. An expensive way to experiment.
If you're stuck with USB, then get the generic adapter from plccable. His stuff works well.

Googled HMI-CAB-C49 hoping for schematics, and got more links back to this site. See here and here.

I'm confident an isolator will work. Try one of these from B&B.

jwyatt8171 said:

Just the charger doesn't seem like it would make a good ground. .

Click to expand...

what this means?

osmanjdt: I mean the charger for the laptop is only supplying dc voltage to the laptop. So, I dont think the laptop is grounded. I may be wrong about this though.

If this is important either rent or borrow an old pc with WinXP or earlier with real serial port or purchase one of these:
http://www.plccable.com/ge-quickpane...03-a-gpw-cb02/

just guess,

use a test pen/neon test light touch on your usb/com body.

RussB said:

If this is important either rent or borrow an old pc with WinXP or earlier with real serial port or purchase one of these:
http://www.plccable.com/ge-quickpane...03-a-gpw-cb02/

Click to expand...

I guess I should have bought that usb cable instead of the rs232 cable i have now.
So, this USB cable will work? Im skeptical because im able to program a quickpanel JR with this same cable and laptop, but not able to program the Quickpanel .

I realized I had an older laptop (WIN98se) that crapped out on me over a year ago. I think that was the laptop I was using to program these, but forgot about that need before ditching the dang thing. UHG....