GE 90-30 Programming Cable

N

Thread Starter

Nate Hemming

I need to make a PC-->PLC programming cable so I can program a GE 90-30 PLC with either VersaPro or LogicMaster. I have the wiring diagrams for the RS422 DB15M end and the DB9F RS232 end.

I'm confused with the something on the diagram; maybe one of you can help me unconfuse myself.

I know there are positive (+) and negative (-) lines for RTS, CTS, RD and SD on the RS422 end which will connect to the PLC. Of course, the RS232 end doesn't have positive and negative for those. Does this have something to do with connecting to the +5VDC line on the RS422 port? (I've attached a copy of the diagram for the RS422 end I've been working with)

How do I compensate for this? Is making a cable a lost cause, and should I give up any hope on making this little device?

Please help if you can,

Thanks,

Nate
[email protected]oo.com
 
D

Dobrowolski, Jacek

Hi Nate,
You need a RS232-RS422 converter between the PC and the PLC. Something like Advantech ADAM-4520.

Regards,

Jacek Dobrowolski
 
P

Peter K. Rauch

Nate,

The serial port on the 90-30 is strictly RS485. The 9-pin D-shell on most computers is strictly RS232. So a direct cable connection is not going to work.

You'll note that the factory supplied GE cable has a RS232-RS485 converter built in.

As I see it you have two options.
1) Get a pci or isa bus card for your pc that has an RS485 serial port. And do the direct connect.

2) Get an RS232-RS485 converter (available form several vendors).

Side note. RS485 has the benefit of supporting much longer transmission distances. Such that one can easily provide terminal access to the PLC from several hundred feet away.
 
A direct cable approach is not going to work. One end of the cable has a different protocal and physical parameters than the other 232 vs. 422. This implies a converter is needed.

You have two options
1) Get a PCI or ISA card for you computer that supports a com port in RS422 natively.

2) Get a converter. I have used this one with success. http://www.kksystems.com/kd485.html

Kind Regards,
Slack
 
I haven't used the 90/30 for a few years, but I seem to remember that we could not make our own cable either. Buy the "Horner Adapter"

later,
Doug
 
The 90-30 and 90-70 both have an RS-485 serial port as already explained. The issue for connection is that both use a 15-pin connector instead of the more common 9 or 25 pin versions. Horner Electric makes a very nice cable for this application that has indicator LED's and is longer than the standard GE cable. The Horner cable has the coverter molded into the cable end so it is a sigle use device. The GE cable has the converter as aseparate device on the end of a 9 pin to 15 pin cable.
In my opinion the Horner is a better solution because of the extra cable length. I'm usually kneeling on the floor with my laptop on an upside down 5 gallon bucket and the GE cable just isn't usually long enough to reach the PLC in the top of the cabinet.

Jmech
 
P

Peter K. Rauch

Nate,

The serial port on the 90-30 is strictly RS485. The 9-pin D-shell on most computers is strictly RS232. So a direct cable connection is not going to work.

You'll note that the factory supplied GE cable has a RS232-RS485 converter built in.

As I see it you have two options.
1) Get a pci or isa bus card for your pc that has an RS485 serial port. And do the direct connect.

2) Get an RS232-RS485 converter (available form several vendors).

Side note. RS485 has the benefit of supporting much longer transmission distances. Such that one can easily provide terminal access to the PLC
from several hundred feet away.
 
K

Kevin Mahoney SI Solutions

Nate-

One item I did not see noted in the previous replys is a limitation on the 5vdc power supplied by the Series 90 PLC's 15pin SNP programming port. If you make a cable much longer than 15' you should use either low impedience cable or an externally powered RS485/232 converter. This is because the 5vdc pin on the port is current limited by an internal, non replacable fuse. If your cable is too long, with a high enough impedience, you will blow this fuse. The port will still work, but no power will be supplied to your converter.

Also, by the time you are done identifying and buying an RS-485 to RS-232 adapter and making the cable, you may have spent as much as just buying a GE Fanuc or Horner Electric cable/converter.

Kevin Mahoney
SI Solutions
207 846 4296
 
B
There is something called a cheater cable we have used for years on 90-30 PLC. It allows you to connect a RS232 to a RS485 port directly and requires no converter. The cable must be 10 ft or less. Email me if you want pin-out. It probably won't cost you more than 5 bucks to build.
 
M

Manmohan Garg

> There is something called a cheater
> cable we have used for years on 90-30 PLC. It allows you to connect a RS232 to
> a RS485 port directly and requires no converter. The cable must be 10 ft or less. Email me if you want pin-out. It
> probably won't cost you more than 5 bucks to build.

Can anyone please send me the details?
 
> There is something called a cheater cable we have used for years on 90-30 PLC. It allows you to connect a RS232 to
> a RS485 port directly and requires no converter. The cable must be 10 ft or less. Email me if you want pin-out. It
> probably won't cost you more than 5 bucks to build.

Can anyone please send me the details?
 
M
> There is something called a cheater cable we have used for years on 90-30 PLC. It allows you to connect a RS232 to
> a RS485 port directly and requires no converter. The cable must be 10 ft or less. It probably won't cost you more than 5 bucks to build.

I would like the pin-out, please.

<b>Moderator's note:</b> I realize this is a very old thread, but does anyone have this information?
 
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