Honeywell Panel Bus is a protocol for IO modules for Honeywell controllers, such as Excel 800, Excel Web II, CPO-PC-6A, LION, EAGLE and EAGLEHAWK. The family of these IO modules includes multiple pluggable modules with just one type of IO each (e.g. 8 analog inputs or 6 relay outputs) or mixture of IO (e.g. 8 AI, 8 AO, 12 BI and 6 BO). Panel Bus modules allow to cover all kinds of applications, which require from tens to hundreds IO points.

Tridium Niagara driver allows to retrofit Honeywell panels by replacing main controller with JACE or any other Niagara-compatible device (Cylon Integra, Johnson Controls FX, Distech Controls EC-BOS etc.) and keeping all IO modules. That greatly reduces the amount of work and price of new controllers. Panel Bus IO points will become available for control by Niagara logic on a standard wiresheet.