Retrotec USACE - Manual (Page 84)

62 ENERGY & PROCESS ASSESSMENT PROTOCOL
the data (intelligent monitoring), but they also may be supported by methods
called rule-based monitoring. Figure 19 shows how these tools might become
integrated in a continuous commissioning system.
Figure 19. Components of an ongoing/continuous commissioning system.
7.5.1 Data Acquisition and Data Logging
Data acquisition and data logging are the original domains of building automa-
tion or building energy management systems. Building automation systems
(BAS) and building energy management systems (BEMS) are proprietary, inte-
grated software/hardware environments. The absence of BAS standardization
coupled with competition for market share results in independent/incompat-
ible system development. BACnet was developed to provide an open (nonpro-
prietary) protocol specifi cation that allows building automation controllers of
different manufacturers to communicate with each; however, BAS/BEMS still
possess nonstandardized proprietary interfaces. Vendor competitiveness has
resulted in BAS/BEMS that provide additional functionality for an enhanced
understanding of performance. Consequently, BAS/BEMS are becoming more
complex over time and are diffi cult for the average operator (given the educa-
tional and experience previously outlined) to understand.
BAS focuses on system operation and includes alarm functionality for pre-
programmed, important criteria. BEMS primarily focus on the major energy-
consuming devices in a facility. Organizations are now realizing the benefi ts of
using both systems. Energy managers do not have the data, information, and
tools necessary to provide optimal results. Maintenance records, energy and
effi ciency reports, and trend analysis should be accessible to energy manag-
ers, but in many cases are not. If they are used correctly, measured HVAC
time-series describe building performance but are wholly dependent on strict
boundary conditions (weather, control strategies, etc.). To describe this situa-
tion, a minimal data set for continuous commissioning was developed in the
projects Building EQ and BuildWise (included in Appendix J).