Serial cable for AB PLC

I mostly connect to our PLCs via ethernet. I went to connect to a PLC via a serial cable and was told by our guy that you have to use a special serial cable or it will blow the serial port on the computer. Is this true or do you use a standard serial cable?

Go to AB Knowledgebase:

https://rockwellautomation.custhelp.com/app/answers/detail/a_id/574907

All AB cables, these info is free you need no contact.

Depends on the PLC/CPU model... Some CPU's have 24VDC on the ports to power up devices, the MicroLogix can be used to power up the AIC's and the SLC also have power

The first 1745-PCC (SLC150) that I made a I blew up the CPU and the PC port also trip the breaker... I think it may have 120 but never checked it

Depends on the PLC, but if it has a DB-9 connector like your computer, then there's a chance you can use a standard null-modem cable. Female to female, with pins 2 and 3 reversed.

If you tell us the specific model PLC, we can confirm the correct cable needed.



-Eric

1769-l35e

Skiroy said:

1769-l35e

Click to expand...

See pdf. Pins 2,3 and 5 are all you need to get connected.

I read that but that doesnt tell me if a standard serial cable from office depot will work without causing a blown port.

Skiroy said:

I read that but that doesnt tell me if a standard serial cable from office depot will work without causing a blown port.

Click to expand...

Most standard null-modem cable will work.

https://www.google.com/search?q=nul...wL1pICYBA&sqi=2&ved=0CFkQsAQ&biw=1755&bih=938

The null-modem cable you require is often called a Serial File Transfer Cable as it can be used to transfer files fron one PC to another PC.
Here is the type of cable you require http://www.belkin.com/us/p/P-F3X171/

I can clarify on the "you'll blow up your serial port !" issue.

MicroLogix 1000, 1200, and 1500 controllers all have a Channel 0 serial port that includes a +24V DC pin.

This pin was provided to power up interface devices like the 1761-NET-AIC, 1761-NET-DNI, and 1761-NET-ENI.

Because the presence of that voltage would damage an ordinary serial port, A-B used an unusual round Mini-DIN8 connector for the Channel 0 serial port of these controllers.

For the MicroLogix 1100 and 1400 controllers, A-B replaced that feature with pins for RS-485.

Any A-B controller with an ordinary 9-pin RS-232 port does not have a 24V power pin. This includes the SLC-5/03, SLC-5/04, SLC-5/05, all ControlLogix and all CompactLogix.

DH-485 network jacks also include a 24 volt supply pin, but have the disadvantage of looking to the uninformed like an Ethernet jack. It's actually fairly common for somebody to plug an SLC-5/03 controller into an Ethernet switch and let out the magic smoke.

Thanks Ken.