BA-92-08-2 — Specification of Spreadsheet Trend Log Sets for DDC/EMCS and HVAC Systems Commissioning, Energy Monitoring, Life Safety Cycles, and Performance-Based Service Contracts

DDC/EMCS (direct digital control/energy management control systems), which utilise personal computers for central building monitoring, can collect, organise, and store system data in spreadsheet programs that can be used to commission the DDC/EMCS system, commission the HVAC systems and subsystems, monitor energy, verify life safety system operation, and monitor performance-based service contracts. Since most DDC systems are not being commissioned properly due to the expense necessary to verify that the complete system is performing as specified and since this represents a tremendous waste of energy and greatly reduced safety, the authors recommend that the submittals require a spreadsheet data base organised in a time-based matrix format called trend log sets, which include measured values, setpoints (and control ranges), operating cycles (economiser, minimum outdoor air, etc.), and calculated values at fixed intervals for a sampling period. This will ensure that the system operates safely and efficiently and will maximise the life of the HVAC equipment. Recommends that the ASHRAE Handbook include the following types of trend log sets for DDC/EMCS commissioning – control stability trend log sets, global systems operation trend log sets, financial/energy trend log sets, and custom trend log sets. This will allow the consulting engineer to precisely specify the commissioning documentation in a format valuable to the owner.

KEYWORDS: commissioning, computer controls, energy management, specifications, monitoring, energy consumption, building management, computer programs, building services, costs, economics, performance