Manufacturers’ tips and tricks for commissioning, balancing buildings
CSE: What factors do you need to take into account regarding commissioning BAS or building management systems (BMS)?
Fluke: Primarily, if a field calibration step is required to verify accuracy of sensor measurement and transmittal, then a CxA commonly uses a handheld temperature/humidity meter to verify the sensor readings and a mA or volts dc clamp meter to verify the control signal (Fluke does not manufacture BacNET or other specific building control signal test tools).
Onset: Probably the most significant factor to take into account when commissioning the BAS or BMS is that things change. The way that an automation system was initially configured is never how it is operating six months (maybe even six weeks) down the road. We hear from about customers projects all the time that were able to realize significant savings just by troubleshooting or providing redundancy to a faulty sensor. One faulty sensor can lead to hundreds of dollars of savings per year. Not to mention that the training of facility personnel that have to interact with the automation systems is highly critical. They may be making modifications to make the system operate more effectively but not comprehending its effects on the systems efficiency. Oftentimes the presentation of real data from the automation system contrasted against the independent data logger findings can really reveal the importance of a holistic approach to managing your automation system.
CSE: What types of tools do you recommend for building commissioning projects? What should be in every commissioning agent’s “toolbox”?
Onset: We recommend that our customers working as building CxAs think about keeping a tidy and comprehensive toolbox of data loggers and sensors to assess the performance of a building. You don’t need many – but having a variety of these tools can allow you to save a lot of time at the job site by quickly identifying problem areas. The HOBO UX90 line of data loggers, for example, provide a variety of measurements in a self-contained package that can help you identify when equipment is cycling too frequently or when lights are on but the room is unoccupied. Our suite of UX100 temperature and relative humidity loggers can help spot trouble areas that might uncover critical re-commissioning requirements of the HVAC system. And many of the loggers we’d recommend for a commissioning toolkit have flexible analog or pulse-based inputs to allow users to connect pre-installed sensors and meters up to them to collect short term data in a way that’s easy to manipulate without accessing the building automation system. That means that data is gathered more quickly and saves the CxA time during the process.
Fluke: Tools such as a multimeter or clamp meter, temperature/humidity meter, air meter, micromanometer, and light meter are all used to verify ventilation, mechanical, and lighting performance under load. In addition, a thermal imager or visual IR thermometer are used to inspect the building envelope. A mA Volts dc clamp meter is used to verify signal continuity in the controls system.