6. How are WACS installed, activated, and tested?

“Installation should be accomplished centrally, alleviating the need to visit every user’s machine and install new software,” Osburn of Siemens said. “Activation often will require coordination with IT resources.”

That coordination, according to Nations of Johnson Controls, normally involves IT-standard procedures such as “assigning IP addresses (and) setting up whatever is needed to address firewalls, ISP connections, etc.”

The Web server should be tested “to assure all specified connection methods are operating and that the data on the Web pages is indeed the correct data from the field devices,” Haakenstad of Alerton Technologies said. For wireless WACS, that simply is “a matter of connecting equipment to a communication dataport, configuring at a secure Website, and sending a test message,” Duffy of Notifact Corp. said.

Web servers can permit offline programming using standard Web-development tools such as Microsoft Front Page, Donlon and Kamal of Computrols said. The key to this is that the building server also allows offline programming and simulation. With special building-automation software, the entire system can be programmed and simulated prior to installation. Also, all of the Web pages can be tested for connectivity. The pre-programmed system then can be shipped and commissioned on site without an on-site Web designer. Testing is strictly limited to the controllers, equipment, and field connections.

7. How are WACS operated and maintained?

Although the operation of WACS is very similar to that of traditional building-automation systems, engineer Bruce L. Billedeaux of Armstrong Service Inc. said, security is much more important with WACS.

“Traditionally, BAS security and passwords management has been very poor,” Billedeaux said. “This is a new facet of worldwide Internet integration that must be considered.”

The maintenance of WACS also is similar to that of conventional building-automation systems, Billedeaux said; however, if a separate server is used, the data interface must be updated when the point list is changed on the BAS component.

“The complexity of this update can vary from automatic to costly and difficult, depending on the equipment and vendor,” Billedeaux said.

Bredeson of Invensys said the operation and maintenance of Web-accessible controls systems is “vendor-specific.”

“Some vendors supply Web servers that host all the graphics and code,” Bredeson said. “Other vendors offer Web hosting at a remote site and charge subscription fees for this service. Maintenance often can be done on-line if the system has Internet connectivity.”

From time to time, the system interface will require firmware upgrades, Ziejewski of Liebert said.

Web servers need to be updated when equipment is added or spaces are modified, Haakenstad of Alerton Technologies said.

To Ehrlich of Trane, the question is not only how WACS are operated and maintained, but who will operate and maintain them.

“In theory, an owner could maintain such a system,” Ehrlich said. “In reality, it probably typically comes back to the installer to maintain it.”

Rae of Delta Controls agreed: “If the end user is technically proficient, he can maintain his or her own WACS. Otherwise, the industry norm would be to enter into a service contract with the installing contractor.”

In any event, Schultz of TAC-Americas said, “The task is not difficult for the individual with the right skills.”

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