Troubleshooting - Johnson Controls - LIT-1201668 - System Integration - LonWorks Integration - 12.0

LonWorks Network Integration with Network Engines and LCS Technical Bulletin

Johnson Controls
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LonWorks Integration
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Technical Bulletin
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Use the information in Table 1 to assist in diagnosing and solving possible LonWorks network system integration problems.

Table 1. LonWorks Network System Integration Troubleshooting Guide




Auto Discovery fails to find all devices after clicking the Relearn button.

The Relearn button calls the last saved relearn data from a queue. Devices added after the last relearn request are not in that data.

Check for device specific resource files and then click the Restart button to rediscover the devices. This causes a poll of current devices and creates a new list.

Auto Discovery fails to find all devices, and clicking the Restart button does not display all devices.

Communication failure

Connect LN-Builder, the COM.PRO Tool, or a third-party LonWorks network configuration tool to the LonWorks network and verify that it is possible to communicate with the devices on the network including the network engine. If communication is good, verify that the network engine database has been generated correctly and that the LonWorks enabled device data corresponds to the devices installed. If the network engine does not respond, verify that the network engine has been correctly installed in the LonWorks network database and that the network configuration image has been sent to the network engine from LN-Builder. If the network engine cannot be installed, replace the network engine.

LonWorks network wires at missing devices not connected properly.

Check the entire LonWorks network. Refer to the LonMark Guidelines – Physical Layer for details (

Critical Resource Missing is shown for the status of the device.

A required XIF resource file is missing from the integration of the controller to the network engine.

Insert the required XIF resource file under the LonWorks Trunk, and then reboot the network engine. See Inserting resource files for details.

Data Conversion Error is indicated as a point's reliability status.

A required resource file is missing from the integration of the controller to the network engine.

This issue may also occur if the Field Units and Units are mismatched.

Insert the required resource files under the LonWorks Trunk. See Inserting resource files for details. If the resource file is present, try rebooting the network engine to see if that resolves your issue.

Routers are not displayed on the Navigation Tree after Auto Discovery.

Routers are only visible in the Engineering view Integration Tree.

From the Engineering view of the LonWorks trunk, select the LonWorks Integration object and click Relearn. Routers are shown in the Integration Tree.

Adding a device under a Router in LN-Builder results in the following Error Message: Node/router on the wrong channel.

The wrong channel was selected in LN-Builder during the insert device process, the device is physically wired incorrectly, or the network interface defined in the LNS database does not match the physical connection to the LON Network.

Change the channel assignment for the device in LN-Builder, rewire the device in the field, or change the channel assignment for the network interface as defined in LN-Builder to match the physical connection to the LON Network.

After defining a LON Integration, adding a resource file extension, and creating an object, the resource file does not download to the NxE. The object created cannot be found or used during Auto Discovery.

Windows 7 and server-class Windows operating systems may require changing the User Access Control (UAC) settings to allow resource files (LON and Vendor Integrations) to be added to the network engines. The Metasys SMP does not inform the user when a resource files fails to download.

Disable UAC settings.