How do you tunnel through an ENC to the BACnet MS/TP devices under the ENC?

Issue

How do you access BACnet MS/TP devices under an ENC without making a direct connection to the MS/TP bus?  Tunneling is supported with LON and ASD devices but there is no tunnel client for BACnet.

Product Line

TAC I/A Series

Environment

WorkPlace Tech Tool release 5.7.x or 5.8.x

ENC with BACnet MS/TP devices

Cause

Want to connect WPT through the ENC to access the MS/TP network attached to the ENC.

Resolution

Tunneling is not required to access MS/TP devices under an ENC.

Since the ENC is already a BACnet device because it has BACnet MS/TP devices connected to it, you can enable BACnet-IP or BACnet-Ethernet on the ENC.  Once either of these protocols have been enabled, the ENC then acts as a BACnet router allowing BACnet communications to the MS/TP devices directly via the ethernet connection to the ENC.

To use the BACnet-IP interface via the ENC, you need to enable the BACnet IP port and enable routing in the BACnet Work Layer properties.  You also want to have "Poll Enabled" in the MstpPort properties.   Make sure that you have defined a different BACnet network number for the BACnetIP network and the BACnet MS/TP network.  To enable the BACnetIP interface you need to expand the BACnet communications tree and enable the port as shown in the following image.