The building automation industry continues to hear more and more about these things called haystack tags, haystack servers, etc., but what exactly are they? There seems to be much confusion and knowledge gaps depending on usage, training, and job roles. First and foremost, haystack, at its core, is an attempt to standardize the way a point is identified and categorized, i.e., a temperature sensor in a room or a flow on the chiller. Any data the automation system brings in is referred to as a point. The core problem haystack is attempting to solve is, “How can code, logic, alarming, and graphics be standardized if every customer wants to name their points differently?” If one customer requires a zone temperature to be labeled ZN-T and another prefers Zone-Temp, how can technicians link their logic to identify those as the same kinds of point? If this problem could be solved, it would create enormous amounts of reusable work, save time, lower costs, and streamline interoperability between automation systems.
The tagging system tends to scare some people off, but, in reality, it is very intuitive. There are three major categories in the hierarchy of tagging. The first is a “site,” which is the location an automation system is controlling. Everything referenced within a site is identified as “equip,” which is short for equipment. Then, there is a “point,” which is the actual point data is read from. Points roll up under equip, and equips roll up under site.