Micro 1500 DeviceNet (1769-SDN) Comms with ABB

[jayfourn8 0]

I am trying to communicate with a MicroLogix 1500 via DeviceNet. The IRC-5 Robot Controller is the master and the the 1500 is the slave. The 1769-SDN (scanner module on the 1500) gives an error 77 which means that the data table sizes do not match. I am unsure of how to decipher the size of the data tables that the ABB is looking for. I configured the PLC scanner module to 70 input words (the first 66 are read only when using the 1500 platform) and 7 output words. I try to put these values in the ABB controller and the 70 value is not allowed. I tried to just use 4 (70-66) as well but that doesnt clear my error either. I have tried many other combinations in hopes of stumbling across the right one but I dont like to work that way. I wish to understand this more clearly so it is definitive and not a guessing game. Thanks!!

[Ken Roach 194]

I think you're operating under some mis-conceptions so let's sort this out. The Module data sizes you configure in RSLogix 500 only affect the transfer if data from the 1769-SDN to the MicroLogix 1500. This data size is variable (and is set to only the Status and Control by default) so that you can conserve I/O data memory in the MicroLogix 1500 controller and only allocate the amount you need to the DeviceNet scanner. I usually start by giving the 1769-SDN the same discrete memory footprint as the 1747-SDN, which means setting the Input file size to (66 + 32 =) 98 words, and setting the Output file size to (2 + 32 =) 34 words. The 1769-SDN can actually handle up to 180 words of input and 180 words of output data on top of those 66 input and 2 output words. The RSNetworx for DeviceNet Scanlist configurator sets up the type, sizes, and memory locations of DeviceNet data exchange connections. Usually the MicroLogix is the scanner and devices like photoeyes, limit switches, I/O blocks, motor starters, and AC drives are the slave devices. You create scanlist entries for the slave devices and "map" them into memory so the 1769-SDN places the data from the field devices into the MicroLogix memory. In your case, the MicroLogix 1500 is the slave device, so you don't put the robot in the scanlist. Instead, you create a "slave data" scanlist entry that allows the Scanlist configurator to place the data that the robot is scanning from the MicroLogix into the data table.

[Ken Roach 194]

When the 1769-SDN is acting as a scanner, it checks the identity and I/O connection sizes of a slave device before it connects and places the connection in run mode. Error code 77 generally indicates that the scanner has determined that a slave device is configured to send and receive different amounts of data than the scanner module expects. When the 1769-SDN is acting as a slave device, it doesn't perform this kind of check, so it doesn't have a reason to display Error 77. Examine the Scanlist in your 1769-SDN and make sure you have not configured the 1769-SDN to act as a Master to the robot, rather than placing a Slave connection data map placeholder in the 1769-SDN scanlist and configuring the robot to be the Master using its own software.

[Kiwi Sparky 0]

Why is the Robot the master? I have used this setup (1769-SDN and IRC-5) on multiple installations and the PLC was always the master and the robot was a slave like a normal DeviceNet node. I use input size 20 and output size 20 on the PLC and map various bits and words to the UDI and UDO table in the IRC5 Can you post youe .DNT file from RSNetworxs, might be able to shed some light for you