from the Programming department...
Allen Bradley PLC to PC cable
PLCs and related questions. topic
Posted by Zafar on 21 July, 2007 - 12:10 pm
I am new in Allen Bradley PLC. i have SLC500 PLC but i don't have its PC interconnecting cable. Please any one help me to make a cable of Allen Bradley to PC interface.

Posted by Bob Peterson on 21 July, 2007 - 4:04 pm
There is a pinout diagram in the manual if you have a 5/03-4-5.

You need an adapter if you have a 5/01-2, or one of the original block style units.

Micrologix units use a proprietary connector so you have to buy the cable from ab.

Posted by Ken Newcomb on 23 July, 2007 - 8:12 pm
Bob is right.

If you have a 9 pin serial on the SLC:
(pinout of 1747-CP3 from AB)

If you have a "phone jack" port:
You have to use a 1747-pic (RS-232 to DH-485 converter)


Posted by Mike on 5 August, 2007 - 2:47 pm
Hello, similar question.

I need some help on making a programming cable for a plc5/20 (1785-l20b)

I don't know much about this stuff (just things I came across looking for diagrams etc).

Apparently it's db9 to db25 (in appearence), however, I need to know the pin to pin configuration before I proceed.

Could someone shed some light for me?


Posted by Trevor Ousey \(list\) on 5 August, 2007 - 7:08 pm
The serial cable for a PLC5 is still a null modem cable, the PLC5 manuals
available from have excellent diagrams.

Posted by Tom Tran on 7 August, 2007 - 1:23 pm

The wiring diagram for this cable is:

RXD 02-------------02 TXD
GND 05-------------07 GND
TXD 03-------------03 RXD

DTR 04-| |-04 RTS
DSR 06-| |-05 CTS

RTS 07-| |-06 DSR
CTS 08-| |-08 CD
|-20 DTR

Basically, this is the pinout for the 1784-CP10 cable.

Good luck.<br>
tom. tran @ Industran. com

Posted by aan - on 7 August, 2007 - 1:40 pm

The configuration for 1784-CP10 cable (PLC-5 serial port to PC serial port) is:

PC (DB-9) PLC-5 (DB-25)

2 ----------------------------------------- 2
5 ----------------------------------------- 7
3 ----------------------------------------- 3
4 -- -- 4
| |
| |
6 -- -- 5
7 -- -- 6
| |
| |
8 -- -- 8
-- 20

I hope this helps.



Posted by Mike on 9 August, 2007 - 7:03 pm
Thanks everyone, I did find the pinout information in the manual listed on Allen Bradley's site. I just had to look harder I guess... and now I have a better understanding of the different cables, etc...

Thanks again,


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