Annex J BACnet/IP devices are designed to provide the way for BACnet systems to grow beyond building-wide or campus-wide internetworks. The author discusses how these new devices can help create systems that cover entire regions and even continents. By Bill Swan
This article covers the basic principle of operation for variable-speed drives: to convert the building's electrical system frequency and voltage to the frequency and voltage required to drive a motor at a speed other than its rated speed. By Mark Ziemer, P.E.
The sizing and selection of flow controls in an industrial or manufacturing project is important, but should not be done in a vacuum. It is just as - if not more - important to remember that the control valve is an integral part of a larger system. By Richard G. Carranza
Many engineers tend to avoid or delegate the nitty gritty of a ground source heat pump system, from soil moisture effects to building system (im) balance. It's time for designers to get in the loop. Learn more about Grounded In Reality in the December issue. Other topics in the December issue include health care HVAC, Boilders, check out the Back2Basics, and more.