From dial-up sequential DDC access via proprietary color graphic vendor programs

to

Real-time multi-building LAN/WAN Ethernet TCP/IP Access

via

Netscape or Microsoft Explorer web browsers

By: Edward H. Brzezowski, P.E.

Created: October 13, 1998

Last Update: December 17, 1998

Update url's February 27, 2001

Up until recently facility managers have had limited choices in the way they connected to their buildings. This typically involved using some type of proprietary vendor program for remote access and communications with stand-alone or networked direct digital controller located in the buildings mechanical equipment room(s).

The operator would normally establish a single dial-up session via their desktop PC equipped with a modem at 1,200 to 56,000 BPS to review the information for a boiler, chiller or HVAC unit in the field that would be displayed in a color graphic window on the screen. Dynamic updates would then occur on the screen at 10 to 60 second intervals. To interrogate the next building or system would require the user to hang up and initiate another dial-up connection that would require a delay of typically 2-4 minutes. Sometimes these remote access sessions would not occur at all if a modem was "locked-up" or malfunctioned in the field.

These stand-alone or networked direct digital controllers (DDC) have been around for many years from a variety of manufactures. The basic DDC controller has analog and digital input/output cards, display, keypad, processing unit with non-volatile memory, HVAC software library and communication port(s). The earliest units (circa 1980-1990) in addition to local displays were equipped with RS-232 ports and external 300-2,400 BPS external "Hayes compatible" modems. The newer unit’s in addition internal modems or external modems operating at 14,400 to 56,000 BPS are equipped with RS-485 or the manufacturers proprietary network.

Much work has been done in the commercial and institutional building market to develop open and non-proprietary network and communication systems to connect these DDC units. This market is now comprised of BacNet, LonMark "open systems" and various manufacturers proprietary networks. The connection between multiple DDC units is typically made on a two-wire network "daisy chained" from unit to unit in the various mechanical equipment rooms (MER). A central DDC unit is then usually designated and connected to outside world via a modem.

The vendor specific and proprietary Microsoft Windows based programs (many requiring single-user software keys or hardware dongles) provided several functions. They typically included:

• Main menu to select operator choices under password authorization

• Color graphic front end to a building system (displaying analog and digital monitoring & control data)
• Remote setpoint adjustments
• Text and graphic data print
• Initial field unit programming
• Data and trend logging
• Archive field unit program storage

In the last few years the communication market has exploded due to the growth of the Internet. Much of this growth can be attributed to the development of the World Wide Web and the web browser. This has resulted in more users becoming "Internet savvy" and familiar with two major web browsers provided by Netscape and Microsoft.

The browsers have become the universal "front end" to many forms of communications soon to approach the quality and speed of TV. In addition to the basic text, graphics, sound and video, vendors and users from around the world continue to develop all types of enhancements and plug-ins to improve the usability and power of the web browser. New versions of enhanced web browsers are made available at low cost or for free every few months. The browser is now being expanded to cover communications with all type of devices from the phone to the TV. New forms of devices called "Internet Appliances" will soon communicate with each other over local area networks (LAN) and wide area networks (WAN). These devices will be assigned unique Internet Protocol (IP) addresses.

Today most users have dial-up modem connections to their Internet Service Provider (ISP). The Ethernet 10BaseT LAN’s in homes, offices and buildings will soon be continuously connected to the Internet. This is happening very rapidly, as lower cost connections become available in the form of wired and wireless connections. Cable modems and high-speed digital subscriber lines communicating via TCP/IP will allow connection speeds in the 500 K BPS to 1.5M BPS to these buildings.

All across the country and around the world miles and miles of cat5 cabling are now being installed to connect computers in these buildings. These communication cables are now running past hundreds of thousands (millions?) of mechanical equipment rooms. These same cat5 cables should also be run to data outlets in the building’s MER(s). Once installed in the MER near the DDC unit a new world of capabilities are emerging and soon to be available.

How do we get this DDC connectivity to the LAN/WAN?

This relatively simple task (w/currently available technology) has become complicated by vendor proprietary systems, BacNet vs. LonMark, and emerging sensor to IP markets.

The building automation manufacturers are supplying and developing gateways to connect their systems to the Ethernet LAN. BacNet and Lonmark vendors are also supplying gateways. In both of these cases the systems are becoming too complicated and requiring more parts that will ultimately have to be serviced and repaired. Right now we can’t see the forest through the trees.

The DDC units need to be equipped with RJ-45 Ethernet connections. They also need to be equipped with embedded web browser/servers capability. The DDC unit would then be assigned with a unique IP address and able to communicate, under secure password connections, with other DDC units (via e-mail?) in the buildings, campus, state, country or world.

What does this mean to the facility manager?

One of the best examples would be in the main office, conference room or command center. In these areas display(s) generated by the "web enabled" DDC units in the field would be able to show continuous information from multiple buildings and systems on the screen at the same time. One screen could be displaying alarm conditions if present, another could be displaying the energy usage and costs for each building with real time totals and monthly projections, and another could display the status of every boiler and chiller. The capabilities are endless especially in light of the low cost of these "web enabled" displays such as WebTV "Ethernet" boxes.

Another capability would be in scheduled and preventive maintenance. The world of service contracts will be turned on its head. Service contracts by vendors (and directly by the manufacturer?) will be possible with continuous connectivity via the Internet. The vendor that provides the best services and can prevent/identify failures or problems before they happen will become part of the facility managers "core team".

Continuous connectivity will also allow new partnering and teaming opportunities with the facility manager. This could include architect/engineers, energy managers, maintenance specialist, energy service companies, energy aggregators, utility companies, contractors and equipment vendors.

Right now there are two missing pieces. The first is the DDC unit with the onboard Ethernet connection and web server/browser. The second is the facility manager’s Internet server front-end package.

The Internet accessible DDC units will be here shortly and the manufacturers will again most likely provide their proprietary color graphic front end but this time they will be using a web browser.

The real power of the "open system" will evolve when open Internet server packages tailored to facility management activities become available that can connect to ANY Internet accessible DDC unit. They will offer the ability to easily and quickly add/delete DDC units from ANY manufacturer. They will also allow the programming, setpoint adjustment and data logging/trending features that was provided in EACH vendors proprietary system. Industrial versions of this type of product are available today.

Each and every DDC manufacturer, building automation and facility management vendor has a unique marketing opportunity awaiting them. They can place their actual building systems or manufacturing plants online and provide the web links in trade journal advertisements and on their web page. Their systems (read and display only mode) would then be available for potential customers, contractors and specifiers to see them in operation 24 hours per day from anywhere in the world.

The future is today…….

The authors web page

If we don’t do this first, maybe our children will

Internet appliances

Embedded LAN and Web browser/server

Stand-alone low cost web servers

Sensor to LAN

HVAC, DDC and Industrial Control

Industrial Facility Automation Servers

Industrial Ethernet PLCs

High bandwidth Internet connectivity