CIP Motion

The key to motion over ethernet is the coordination of clocks over the network.  Managed switches, controllers and CIP drives have internal clocks that are synced to a master clock based on their calculated time to send a packet of information. The Ethernet device containing the master clock is either predetermined in a larger ethernet architecture or is defaulted to the clock in the controller for smaller or isolated systems.  The clocks in each device are synched every second according to IEEE 1588-2008.

Servo drives keep a queue of motion commands sent from the controller with time stamps on them so they know when to execute.  This makes it so each servo drive will execute at the same time as every other drive synced to the master clock regardless of when they received the packet for the motion.  Though the CIP enabled drives can receive commands in advance, too many packets being delivered over the network without proper prioritization and even information loops created from using unmanaged switches can prevent motion instructions from reaching drives in time.  For this purpose, it is crucial to have a proper network architecture.

Kinetix 5500/5700/6500

Whenever possible, it is best to connect CIP motion drives directly to the controller they are receiving commands from.  Motion drives typically take a lot of bandwidth, so if they are linked in a chain, put the drives needing the fastest update rates closer to the controller.  This really only needs to be focused on if the motors are all the same size, otherwise it is likely in your best interest to follow the drive user manual and put the larger drives in the front of a power sharing configuration, and do a simple daisy chain as opposed to a rats nest of ethernet cables. Other ethernet devices including switches without CIP Sync (PTP)  and CIP encoders should be put after a series of drives

Managed switches with PTP can be placed in between drives and the controller with little to no drop in performance as they properly prioritize motion information packets over other packets that are less time sensitive.  If the drives are put in a daisy chain with other ethernet products, put the drives closest to the switch.

It is a good idea to check with Integrated Architecture Builder to make sure your switches and controllers aren’t overloaded with  data.

Kinetix 350

In the case of the Kinetix 350 that has only 1 ethernet port, daisy chaining drives is impossible, so if there are multiple drives, they will need to be connected to a switch and then to a controller.

  • < 4 Kinetix 350 drives, a lightly managed switch such as the Stratix 2500 is going to work fine.
  • For 4-8 axes, a managed switch such as a Stratix 5700 full can be used.
  • > 8 axes are utilized, a Stratix 5700 with PTP will need to be utilized

These guidelines should be followed unless the update rates on the axes are very slow and need no coordination between axes.  From a price point, unless you have 240V power single phase and thus can utilize the 2097-V32PRx-LM series of the Kinetix 350, it becomes cheaper to switch to the Kinetix 5500 at 2 axes for larger drives that might fall in the PR5 or PR6 range, and at 4 axes for smaller drives in the PR0-PR2 range due to the power sharing ability of the Kinetix 5500

 

Switch Setup

Initiating the Express Setup feature on the Stratix 5700 runs a macro which sets many parameters, including the configuration of QoS (Quality of Service) settings and classifying CIP, PTP, and other traffic (does not apply to switches with lite firmware revisions). This will allow prioritizing of packets that are more important in a typical industrial automation application, like standard and safety I/O, PTP (base for CIP Motion and CIP Synch).  For the Stratix 2500, Express Setup will configure a QoS that simply prioritizes automation traffic over information traffic and does not have advanced parameters for managing clocking like in the Stratix 5700 or 5400.

Setting up the switch initially with Express Setup

  1. Turn off laptop WIFI. Set LAN settings to obtain IP address automatically
  2. Run Express Setup
    1. Apply power to the switch.
    2. Make sure that the power on sequence has completed by verifying that the EIP Mod and Setup status indicators are flashing green. If the switch fails the power on sequence, the EIP Mod status indicator turns red.
    3. Press and release the Express Setup button. Wait for a few seconds until the status indicator on one of the unconnected switch ports flashes green.
  3. Connect Ethernet cable from the flashing switch port to laptop Ethernet port.
  4. While the Setup status indicator flashes green, start an Internet browser session on the personal computer and navigate to http://169.254.0.1/express-setup.htm
    1. If you have a home page configured, the switch configuration loads instead of your normal home page. The switch prompts you for the default switch username and password.
  5. The default user name is admin. Enter the default switch password: switch.
  6. Complete the Network Settings below:
    1. Host Name (no spaces in name, spaces not allowed)
    2. IP Assignment Mode
    3. IP Address
    4. Password
  7. Complete the CIP VLAN Settings below:
    1. IP Address
  8. Click Submit – The switch initializes its configuration for typical industrial EtherNet/IP applications. The switch then redirects you to the logon page for the Device Manager web interface. You can continue to launch the Device Manager web interface for further configuration or exit the application. The user name is: see 6.a above. Enter password: see 6.d above.
  9. If your browser does not automatically refresh, navigate to 169.254.0.1/xhome.html in a different browser or click refresh
  10. After you complete Express Setup, refresh your PC IP address:
    1. For a dynamically-assigned IP address, disconnect the personal computer from the switch, and reconnect the personal computer to the network. The network DHCP server assigns a new IP address to the personal computer.
    2. For a statically-assigned IP address, change it to the previously configured IP address.