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Trying to hook an SLC 500 up to a PC to monitor data

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salmans

Computer
Apr 17, 2003
4
I've just started working with PLC's so please bare with me. I'm trying to hook a PC (loaded with Rockwell's RSlogix software) to an SLC 500 (which is part of an Austemper Belt Furnace). The SLC has what looks like an ethernet connector on the front of it. I cant find much info on it except that is uses RS-485 wiring standard.
Has anyone ever done this? If so any info would be greatly appreciated. I dont want to load programs into the SLC, just monitor data, such as temeratures. Thanks muchly.

Bob///
 
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You will probably have to purchase the Allen Bradley KTX card and install it into your computer. This card is somewhat expensive though. You will also need RSlinx. After that instead of buying RSview you could you MS Access to monitor your variables.
 
Probably the most common way of hooking up to your RS-485 is with the 1747-PIC device. It is an interface device that connects to the serial port on your pc and the RS-485 port on the plc.
As joe818 has said if the plc has a serial port use it as it takes a null modem serial cable to connect your pc to the plc.
To use the serial cable, select the RS232 DF1 driver in RSLinxLite (which came with your RSLogix), and use the auto configure to set up the communications.
There are other fancier ways of monitoring your temperatures if you have the need for a much more permament solution.
 
The 1747-PIC will convert the info from your com port to the DH485 protocol.
If you only have an RJ45 connector on the front of your SLC500, then you have a 500 (fixed unit)5/01 or 5/02 processor and you will have to use the PIC or another DH485 converter.
If you also have a 9 pin serial connector, then you will have less problems using that port Ch0 to make your connections. The PIC driver is notorious for "hogging" the com port and will persist in making the com port look busy even after it has been deleted. (until the PC is completely powered down)
 
the PIC devices are known to have communication problems after a certain version of RSLinx is downloaded.
It seems, that Allen Bradley is phasing this product out, in favor of the much more expensive PCMK card. The PCMK card is interfaced to a laptop through the PCMCIA slot. The PCMCIA slot must be of a certain type. The RJ45 connector you are speaking of is DH485. You will also need to Purchase the cable that connects the PCMK card to the DH485 port on your SLC processor. Best regards, PLCSAVVY

 
If you buy RSLinx and use the DF1 driver through the serial port you can then map this data to an excel spreadsheet. I use this for commisioning purposes when the job does not have a HMI or SCADA front end. You can actually make quite a good SCADA page from Excel using conditional formatting for animation, and If your clever you can even write to the PLC using pushbuttons written in VBA using DDE pokes.

Richy Wiseman
Control Systems Engineer


 
You don't need a PIC just go to Radio Shack and get a NULL MODEM for the 9 pin serial cable (If you have a serial port on your SLC). It works, PIC's stink! What is the Part Number on your SLC. I don't think you get DDE to work with LINX unless you get Linx Pro. Linx Lite comes with RSLogix.
 
PaulT587 is correct, the rslinx lite which comes with RSLogix 500 does not support DDE OR OPC. You will need to purchase RSLinx Professional or a third party software driver. best regards, PLCSAVVY.
 
Sounds like the guy is trying to connect the plc to program. Even though HMI and DDE got mentioned because of the word "PC".

The last TWO post sound more relevant to what you are trying to do.

First can you tell us what kind of PLC? Look on the front for some numbers: 5/01, 5/02, 5/03, 5/04 or 5/05?

If you have a 5/03 or 5/04. You can use the radio shack special DB 9 cable. Start RS LINX, and click on Communications then Configure a New Driver.

Click on the pull down bar, and find
RS-232 DF1 Driver, normally the first one on the list.

Then click on ADD New.
The default name is ok. AB_DF1

Choose under DEVICE pull down box the choice: "SLC-CH0/Micro/PanelView"

Now here is the easy part. Make sure your Radio Shack cable mentioned above is connected to the DB9 connector on the front port of the PLC and you have the other end connected to the DB9 port of your computer.

Click on the button that says "Auto Configure" If you have the right cable and everything is connected right, you should get a "successful" in the box.

You should see your driver in the table below as running.

Next, close that driver box, then expand the driver on the left column. This will active it. Hopefully you'll see TWO icons in a second pop up.

One will be your computer, the other your PLC.

Now just minimize RS LINX and start your programming software RS Logix...if you need help from here, post back.



Chris Elston
Automation & Controls Engineer
Download Sample PLC Ladder Logic Code
at MrPLC.com
 
Sorry I didn't mean to say:

"Sounds like the guy is trying to connect the plc to program"

I meant to say:

"Sounds like the guy is trying to connect the plc to monitor his program" (like in RS Logix.) Or Monitor the data tables.

Chris Elston
Automation & Controls Engineer
Download Sample PLC Ladder Logic Code
at MrPLC.com
 
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