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Version: 8.1

Connecting to SLC

Inductive University

Connecting to SLC

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Connect to a Device

  1. Go to the Config section of the Gateway Webpage.

  2. Scroll down and select OPC UA > Device Connections.

    Connecting to SLC Step 2

  3. On the Devices page, click on Create new Device.

  4. Select Allen-Bradley SLC, and click Next.


    These PLCs do not have a native Ethernet connection, therefore another device like a Net ENI or an ENBT must be used for the connection.

    Connecting to SLC Step 4

  5. Fill in the following fields:

    • Name: SLC
    • Hostname: IP address for the PLC, for example

    Leave the default values in the remaining fields.

    Connecting to SLC Step 5

  6. Click Create New Device. The Devices page is displayed showing the SLC device is added to Ignition. The Status will show as Disconnected and then Connected.

    Connecting to SLC Step 6

  7. To see all the tags, go to OPC Client > Quick Client in the Config section. On the OPC Quick Client page, expand the SLC folder and in the Global folder you can see all the tags.

Device Connection Settings

The General settings are common to all Allen Bradley devices, and the Connectivity settings are device dependent.

General Settings

NameThe user-defined name for this Device. The name chosen will show up in OPC Item Paths and under OPC-UA Server > Devices of the Configure page of the Gateway. The Device Name must be alphanumeric.
DescriptionTThe user-defined description for the device. This is only used as a note to differentiate between devices.
Enable DeviceOnly devices that are enabled appear in Connections > Devices of the Status page of the Gateway and thus have their tags available for use.

Connectivity Settings

HostnameThe Hostname value is the IP Address of the SLC processor. The protocol that the SLC processor supports is automatically detected. It will use either CSP protocol on port 2222 (0x8AE) or EthernetIP protocol on port 44818 (0xAF12).
Local Address
New in 8.1.8
The local address to connect from when establishing a TCP connection. If left blank, then the driver will simply pick an available address.
Communication TimeoutAfter sending a request to the SLC processor, the Communication Timeout setting is the amount of time in milliseconds to wait for a response before treating it as a failure.
Browse Cache TimeoutWhen the data table layout is read from the SLC processor, the Browse Cache Timeout value is the amount of time in milliseconds to cache the results.
Connection PathThe Connection Path value is used to define the route of the SLC processor to connect to. Currently routing through the ControlLogix Ethernet Communication Interface Module (1756-ENET)to the ControlLogix Data Highway Plus-Remote I/O Communication Interface Module (1756-DHRIO) and on to a SLC processor of the DH+ network is supported.

Advanced Settings

Disable Processor BrowseDisables the processor browse setting. (Default is false.)
Zero TNS ConnectionDisables the Zero TNS connection setting. (Default is false.)

More Information On Connection Path

The Connection Path format contains 4 numbers separated by commas. The first number is always 1 and tells the 1756-ENET module to route through the backplane. The second number is the slot number of the 1756-DHRIO module of the DH+ network the SLC processor is connected to. The third number is the channel of the 1756-DHRIO module that the SLC processor is connected to. Use 2 for channel A and 3 for channel B. The final and fourth number is the DH+ node number. This number is in octal and is the same as configured in the SLC processor. See the ControlLogix Ethernet Communication interface Module User Manual for more information.

  • Connection Path Format: 1,<1756-DHRIO slot number>,<1756-DHRIO channel>,<DH+ node number>

The valid range for the 1756-DHRIO slot number is between 0 and 16 but depends on the chassis size. The 1756-DHRIO channel is either 2 for channel A or 3 for channel B. The DH+ node number range is from 00 to 77 octal.

Supported SLC Connection Methods

  • SLC505 direct
  • SLC505, SLC504, SLC503 connected through 1761-NET-ENI
  • SLC504 connected through 1756-DHRIO
  • SLC505, SLC504, SLC503 connected through Spectrum Controls WebPort 500