jayA485

SLC500 Communication Trouble

26 posts in this topic

I have some SLC500 that I am attempting to connect to for the first time. I am using a PC with USB, an AB-1747-UIC A with USB connection, running through a DH-485 Link Coupler to the CPU. I have configured a DF1 driver, and a UIC driver both successfully in RS Linx, but the CPU will not show up in RS Who, therefore I cannot connect to it. I have tested that the connection is good to the CPU, as the driver would not be successful otherwise. I cannot figure out why the PLC does not populate in RS Who. Any ideas?

Edited by jayA485

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The 1747-UIC is a DF1 to DH485 converter. So the port on your PLC must be configured for DH485 protocol.

Which SLC500 do you have SLC500/01,02,03,04 or /05 

and which port are you connected to? And is that port configured for DH485?

Cables used are?

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SLC5/02 CPU with only an RJ45 port. (I also attempted a 5/03 with RJ45 and Serial ports, I tried switching my UIC to RS232 with serial cable and did not get a connection). The DF1 driver auto configure is successful with my USB 1747 UIC with an Ethernet cable (straight) directly to the CPU or using the DH-485 Link Coupler. The only non-Allen Bradley cable I am using is the Ethernet. Some other info I found said it would work. (For confirmation I have changed Ethernet cables with the same result including a cross connect cable).

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The RJ45 connector on the front of a SLC 5/02 is not ethernet.  It is DH-485 (electrically RS-485).  Try using the AB cable called out for the UIC to SLC connection.  Or make one.

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Here's a list. basically it just needs the 1747-uic device (Make sure the switch on it is clicked to the right position, otherwise it will be trying to use the DB9 instead of the rj45). then go to a standard rj45 (ethernet) cable. use the 1747 uic device driver which only asks for the comm port needed, it shouldn't have an auto-configure button on the driver needed.

 

Whatever you do, just don't use a crossover cable with the RJ45.... things may burn up at that point.

cables.PNG

Edited by IanM8040

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This driver used for dh485 uic device

 

 

driver.PNG

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Try a different station number on the UIC (in RSLinx).

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I had done the UIC driver previously, but had no confirmation of it working. (With the DF1 driver configuration would work meant I had good connection even though the PLC would not populate in RSWho). So, using the UIC driver, I still have no population in RSWho. I took a screen shot of the station menu as I do not know how to change that, and all options are grey'ed out. (Still using a standard Ethernet cable on this connection - I have not yet made a custom cable).

RSWho_Station.png

RSWho_UIC.png

UICDriver.png

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You change it in the "Configure UIC Devices" popup window.  That station number is for the UIC itself.  If it is the same as the PLC's station number, you won't see the PLC.

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I have now made my own cable. I had an extra AB-1747-C10.03 S-B (with a large connector on one end and RJ45 on other). I followed a pin out I found online:

CABLE PINOUTS:
Data Highway 485 (DH485) Communication Cables:
1747-C10/C11/C13/C20 CABLE PINOUT & CONNECTOR PART NUMBERS

P1 / COLOR / FUNCTION / P2
1 / RED / CH. B TX/RC / 1 TOP
2 / BLACK / CH. A TX/RC / 2
3 / BROWN / +24 VDC / 3 **
4 / WHITE / SIGNAL GND / 4
5 / BLUE / TX-EN / 5
6 / DRAIN / EARTH GND / 6 **
7 / GREEN / SIGNAL GND / 7
8 / ORANGE / +24 VDC / 8 BOTTOM

 

I have also switched to using a PC with Win 7 instead of 10... and I have the same result. Using the UIC driver, the PLC does not populate in RSWho. I again ran the DF1 driver autoconfiguration to confirm my cables were working. (The cable I made was tested before use with a network cable tester). 

Using the 1747-UIC, the USB and DH485 lights flash from time to time with the OI light solid. 

I tried hooking up a 5/03 CPU which had an RJ45 and a serial port. I tried to use the 1747-UIC switched to RS232 directly to the serial port on CPU with an AB-1747-CP3 cable that did not work. I also tried the RJ45 on the 5/03, the DH-485 light was blinking, but the drivers would never confirm connection.

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I did try changing the station number from 00 to 01 I lost communication with my PC (had a red X over the workstation I am using). Went back to 00 and still had the X. When I tried to config again, RSLinxs crashed. Upon reload Im back at 00 with no X.

Edited by jayA485

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I am using the gray/White 1747-UIC Ser A converter. I am trying to follow the steps in the link provided IanM8040. I have not ever seen the black version shown. Earlier in the forum I was told to use the UIC driver, but as I stated, using the DF1-DH485 Driver, I get a successful auto configuration, but the PLC does not populate in RSWho. This is still the case. I do not have another 1747-UIC to compare, but I have requested another for order. I made my own 1747-C13 cable, and have tried ethernet cables with the same result. I have tired with and without the link coupler, and also I have tried 2 different 5/02's and also a 5/03 (on the 5/03 I also tried the RS232 with the 1747-CP3 cable). 

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The forum is having issues with any more images I am trying to attach.

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The black UIC device in the link is just a third-party device. 

 

have you tried deleting the harmony files for rslinx? 

 

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Update: Still waiting on a new UIC cable to verify if mine is working. Decided to order a Compact Logix CPU as I may have better luck upgrading and waiting a couple months for that to come in. 

I have no idea what the harmony files are. I will follow your link and educate myself. 

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The problem with using an ethernet cable is that the 24volts on the plc socket can damage a UIC, that's why you should use the correct C13 cable as it only has 3 pairs instead of 4 pairs.

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Thank you Alan, that is excellent information. While I am waiting on the factory UIC and C13, I did make a C13 (after I had tried the ethernet).

 

FYI: My need to connect to the SLC502 started with a technician plugging an ethernet into the SLC502 to communicate directly with the laptop ethernet port. They had assumed the RJ45 port was ethernet. The power supply blew. He plugged in another power supply and tried again and blew that one. Then decided to stop. The SLC502 in the rack seems fine, but will not run, or communicate with the HMI. So we believe the program may have been lost. I have the program, but need to download it. 

Edited by jayA485
add info

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It sounds more like that the Comms port on the SLC is no good.

If the program was lost or corrupted then the Fault light would be flashing red.

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Regarding my attempts to connect not working: I am using several new SLC CPUs without luck. The CPU in question does not have any lights when connected normally. If I disconnect the Comm port, the Comm light comes on. I have been wanting to connect to it to see why it won't Run. Engaging the HMI buttons change the HMI screen, but no I/Os change on the PLC including the Run light not lit. This follows the logic of the Comms port being damaged you mention. However, I cannot connect to any of my other SLC's yet to download the program. 

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Update, received my new 1747-UIC today. It works!. I heard from several helpful individuals who told me to verify cabling. It just took a while. Thank you all so much.

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I read somewhere in one of the manuals that the C13 cable floats pin 3 and that using a cat5/5e/6/6e patch cable will brick the UIC when 24vdc hits it.  This may be what happened to you.

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On 1/22/2022 at 7:26 PM, BobLfoot said:

I read somewhere in one of the manuals that the C13 cable floats pin 3 and that using a cat5/5e/6/6e patch cable will brick the UIC when 24vdc hits it.  This may be what happened to you.

This is what happens for sure. 3 and 6 aren't landed in the c13 cable. I probably didn't outline that enough in an earlier reply when I mentioned not to use a crossover cable!

 

Reminds me of when I was a floor technician and got called to a machine where an engineer attempted to connect to a 5/03 directly to the ethernet port on his laptop, the entire line was down until we found out what happened. I was a little wary of touching anything with the 'fakernet' ports until I read up on it and realized what happened.

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Unfortunately, you can't predict the communications network/hardware just by the type of connector, even on current products. Current Red Lion HMIs use RJ45 and RJ12 ports for their serial and RS485 networks,  sometimes having more than 1 COM port on a single connector. The C-More HMI on my desk has a DC15 connector for RS234/422/485, a 3-pin Phoenix connector for RS485, and an RJ12 for RS232C. Both also have an RJ45 port for Ethernet.

Another war story: my last location had a bunch of Siemens S7-300 PLCs. I plugged into one of them with a USB PC adapter to the DE9 port on the front and couldn't connect. I had just finished using it on another machine with no issues so I went back to the first machine and it also didn't work any more. I hunted around for another PC adapter. Before plugging it in, I noticed a null modem adapter on the PLC. I missed it the first time because the PLC was down low and it was not a well-lit area so I was going mostly by feel. I'd guess that someone tried to connect with a serial cable (definitely won't work  unless you have a Siemens PG) and used a null modem adapter and accidentally left it there. The MPI port on the S7 has 24V on a couple of pins which, having the null modem adapter in place, fried the PC adapter. Instant $500+ brick. I never found out who left the adapter there, but the serial ports of all of the other PCs that connect to PLCs still worked. I learned a lesson to double-check all ports for extraneous adapters before plugging in.

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