BACnet troubleshooting

This topic summarizes things to do to resolve certain BACnet networking problems.

When I start a station the BACnet/Ethernet Port goes into fault with the message, “Verify WinPcap 4.1.x is installed.”

WinPcap must be manually installed to use BACnet/Ethernet on supported Niagara 4 Windows platforms. Download the utility from https://www.winpcap.org/install/, install it, and restart the station.

I have connected all network devices as described in the documentation, but Workbench fails to discover any devices.

Failure to discover may be due to:

  • duplicate mac addresses
  • mis-configured baud rates
  • a max master that is too small

Use bacnetUtil to diagnose the above problems.

How can I diagnose intermittent MS/TP network problems

The BTokens component may be the most useful MS/TP troubleshooting tool. This component provides visibility into the health of an MS/TP network at a new level. Previously this type of information could only be gathered by observing and interpreting the blink pattern of the device’s serial activity LEDs. Knowing the bus is healthy at the token passing level may help shift the focus of an investigation to a remotely solvable configuration problem that does not require dispatching a technician to the site to investigate.

Initial offsite diagnosis of intermittent problems can be performed using the BTokens component, standard Niagara point extensions and web charts. For example, you can detect interruptions in bus communications by graphing several relay values on the same WebChart as the tokens per second and monitoring the bus health.

How can I improve performance of older devices

Device overrides can be a useful tool for managing performance limitations in some devices. For example, older devices in the field may claim support for features like “readPropertyMultiple” (answering multiple questions per request), but do not do a great job of answering large multiple question requests in a timely manner. Those older devices may be able to more quickly respond to 30 separate requests containing only one question, than one request containing 30 questions. Adding an rpmOverride to the device may improve overall performance of communication with the device by instructing Niagara to send only single question requests to the device.