Compact logix L31 comms problems

[kevbloke]

Good morning all, I'm having problems connecting to an AB L31. I'm using an Allen Bradley 1756CP3/A lead through a USB 232 converter. Software is RSLogix 5000 V17.00. The project has been created with this software.
When I click on Who active? nothing is detected. It has path: AB_DF1. Path in project: None. I've tried CH0 and CH1 but no joy.
Any ideas please

 

[dmargineau]

What type of Serial RS232-to-USB converter are you using?
Although I have used several Belkin upper price tier ones, the Tripp-Lite USA-19HS seems to be the best choice for Allen-Bradley manufactured CPUs.
http://www.tripplite.com/en/products/model.cfm?txtModelID=3914
If the Default communications settings for the CLX CPU's Channel 0 System Protocol have not been modified, define the DF1 RSLinx driver pointing to the USB-to-Serial adapter's Device Manager "Comm.Port #" and using the Auto-Configure feature, while making sure there aren't any other RSLinx configured DF1 drivers or PC applications using the Serial Comm. Port.
If the original settings of the CPU's Serial RS232 port have been previously modified, I am afraid you will have to use some other communications means in order to "connect" to the controller; the easiest and most efficient will be the inserting of an EtherNet/IP bridge (1756-ENBT) within the Local Chassis (hopefully there is at least one unused slot)and 'patching" your PC's NIC to the ENBT's Ethernet port; if the ENBT's IP Address and the PC's NIC interface's one are "subnet compatible" (carrying identical first three octets) you should be able to connect to the CLX CPU using an EtherNet/IP RSLinx driver.