In MNB-1000 (Plant Controller) firmware Revision 1.50E, the Spanning Tree Protocol is Disabled, by default.

Issue

In MNB-1000 (Plant Controller) firmware Revision 1.50E, the Spanning Tree Protocol is Disabled, by default.

All previous versions were shipped with the Spanning Tree Protocol enabled.

Product Line

TAC I/A Series

Environment

I/A Series MNB-1000 (Plant Controller), firmware Revision 1.50E and later.

Cause

In some cases where multiple BACnet routers (eg, MNB-1000, UNC, ENC, etc) were installed on the same BACnet-IP internetwork, having the Spanning Tree Protocol enabled in the MNB-1000 would allow a "router loop".

Resolution

Be aware that in MNB-1000s with firmware Revision 1.50E and later, the Spanning Tree protocol is disabled, by default.

Click here to see the Release Notes for firmware Revision 1.50E .