The Kennedy Controls Corporation specializes in innovative solutions to complex business problems.
Computer Controlled Energy Management System.
Frequently Asked Questions
The KenTrol Energy Miser is a building energy management system. It's main component is a Windows PC based software and hardware package that controls heating and cooling systems. It also has an optional building intrusion and fire alarm system (KENTROL ALARM) plus video surveillance (KENTROL VIDEO) modules.
The building energy control system uses the computing and data gathering capability of the modern PC to make calculations for the utmost savings in fuel. There are three major components. First is a ‘black box’ called a WatchDog that is normally used wherever there is a thermostat in the building. It replaces the thermostat and supplies data to the computer. WatchDogs are connected to each other in a daisy chain, and the end of the daisy chain is connected to a second type of ‘black box’ called a BusMaster that connects to an ordinary LAN. The computer running the KenTrol Energy Miser software is in turn connected to the LAN.
After this simple installation, the computer gathers data and exercisescontrol of the heating and cooling equipment to provide maximum savings in energy. The longer the system is installed, the greater the savings as the computer learns the individual heated or cooled area’s characteristics.
When the temperature of the building is the same inside as the temperature outside, virtually no energy flows in or out of the building. Hence, when the building is unoccupied (off peak usage), the temperature can be allowed to drift toward the outside temperature, energy is not consumed. Obviously the longer it can be kept in that state, the more the savings. The trick is to maximize both the depth of the setback and the duration.
That’s the hard part. It takes a computer running sophisticated software accompanied with appropriate remote hardware in the building to get the best maximization of the setback. The computer must know the individual heating (or cooling) characteristics for each zone, and be able to calculate how deep the setback can be, and for what duration. . . consistent with being able to get the zone back up to the proper temperature by the next occupied period (on peak usage).
The KenTrol Energy Miser uses WatchDogs to gather information and control heating and cooling equipment so the computer can limit the energy input to the building. The building energy consumption will be nearly zero if the temperatures inside and outside are the same. . . the KenTrol Energy Miser computer simply calculates the periods where the building temperature can be allowed to approach the outside temperature (hence zero energy input) and, within the capability of the heating or cooling system, have the temperature back to the desired level before the next scheduled building usage period. Of course a minimum temperature (normally above freezing) is maintained at all times in very cold climates.
The computer does four important functions. First it maintains a ‘calendar’ where the building administrator sets the times when the building is to be 'at temperature’. Second, it sends signals to the WatchDogs at the appropriate times to have the building up to temperature as required. Third, it gathers data from the building as to how it responds to energy input versus the outside conditions. Fourth, it makes continuous calculations based on a combined calculus function called PID to determine the maximum amount of time the energy can be off and still have the building at temperature when it is next desired.
The only way the maximum savings can be achieved is with the data gathering and computing power of the modern computer. Each room in the building is analyzed by the computer as it learns the room’s response to energy input versus the outside conditions. For each scheduled off peak or setback period, the computer makes a decision as to how ‘deep’ the setback can be, and for how long. Obviously if the room is not to be used over a holiday weekend a deeper as well as longer setback can be utilized.
The installation is not complex. Systems have been installed by building owners, building maintenance people, electrical contractors, HVAC contractors, etc. The installation consists mostly of replacing the existing thermostats with WatchDogs and connecting the WatchDogs through a BusMaster to the computer using simple 'RJ' telephone type connectors.
There is no reason for anyone to need routine access to the ‘black boxes’, there are no user controls on them, etc. They are normally mounted out of sight or out of reach of the normal building occupants, with the temperature sensors extended to the former thermostat locations. It is typical for the WatchDogs and BusMasters to be mounted above a suspended ceiling, near the ceiling level, in a utility closet, or in a NEMA 1 type hinge cover box.
The KenTrol Energy Miser has an optional software module that can be used to provide the function of a modern security system. It can monitor door switches; motion detectors; smoke, CO and fire sensors, etc. From these inputs WatchDogs send information to the computer where it is processed and appropriate action is taken – see the Messaging section below.
Yes, the system can be expanded at any time by simply connecting additional units to it. In fact it is common for building administrators to add functions for the Kentrol Energy Miser to control after they become familiar with the tertiary capabilities it has.
Since the communication to the computer is via an ordinary TCP/IP LAN, the computer and the BusMasters can really be anywhere the LAN protocol is present. Although not particularly recommended, it is theoretically possible to have the computer nearly anywhere. . . not necessarily in the building being served. A group of buildings on a common campus and that have a well maintained WAN can easily be controlled by a single computer.
A common setup is to have a control computer running the Kentrol Energy Miser software in each building, with the capability to ‘remote into’ the individual building’s computer via either a local WAN, or through the Internet using MSTSC or similar remote control software. In this manner a number of buildings can easily be observed or controlled from virtually anywhere in the world, yet each building has its own stand alone system.
The Kentrol Energy Miser system will work with nearly any sort of heating or cooling system. Most can simply have the thermostat replaced with a WatchDog and be in business. There are uncommon, proprietary, systems that integrate zone duct dampers, multiple speed blowers, etc. that require investigation prior to conversion.
Certainly. The control software allows you to exercise whatever degree of control you wish. . . if for instance a meeting has been scheduled at the last minute for an after hours time that was previously designated as ‘off peak’, it can immediately be set to return to normal temperature from the console.
The data gathering and control function is handled by the WatchDogs. Each WatchDog contains a PIC chip that remembers the control function (i.e. holds the desired temperature), and transmits the input data to the computer. The WatchDogs are connected in series to a BusMaster via a proprietary network and power distribution system – the WatchDogs are powered by the BusMaster. The BusMaster, in turn, interfaces the WatchDog communication with an ordinary TCP/IP LAN. This could be an existing building LAN, or could be a dedicated LAN for the Kentrol Energy Miser system. Of course the control computer is also on this LAN. In this way the computer can communicate with all the WatchDogs. Both the proprietary network between the WatchDogs and the BusMaster and the TCP/IP LAN use ordinary CAT 5 cable. WatchDogs are connected to each other by RJ-11 connectors, and of course the TCP/IP LAN uses RJ-45 connectors.
Control of a given room’s temperature is easily set via the control computer. If a certain room needs to be a few degrees higher or lower than others, it can be set individually. The temperature can be set at any time – changed for a particular purpose for a short period, etc. Occupants that do not have access to the control computer cannot, of course, change the temperature set point. In many building heating and cooling applications this is an important feature as the occupants may frequently over heat or over cool the building, thus wasting large amounts of energy unnecessarily. Incidentally, the Kentrol Energy Miser system keeps a record of each room’s temperature that can be displayed as a graph – so anyone can be shown that the room was on temperature as specified, should they complain.
The Kentrol Energy Miser system is designed to run on an ordinary PC equipped with a LAN card. The capability of the computer determines how many BusMasters and WatchDogs can be handled satisfactorily. Microsoft Windows XP is the recommended operating system, although Windows NT is acceptable. For most applications the machine should have a Pentium 4 CPU operating at 2.66 GHz and be equipped with 512 MB of ram.?
In theory, yes, but it is not recommended. Because of the importance of the energy monitoring and controlling function and because of the potential ‘down side’ if it fails, it is not advisable to take the risk of having the computer do anything else because of a potential conflict – including one that might not be obvious. Besides that, the KenTrol Energy Miser software will keep the computer pretty busy – it might not be a very good machine for other functions.
In typical configurations, the Kentrol Energy Miser system can handle over 200 WatchDogs and over 100 BusMasters if connected to a computer that is fast enough to service them adequately (like the unit specified above). A further limitation is that one BusMaster can power only 20 WatchDogs. If more WatchDogs are necessary, either a separate power source can be added for them, or another BusMaster can be used. Normally the building layout behooves one to provide several BusMasters, so this is seldom a problem. The maximum cable length from the BusMaster to a single WatchDog is 3000 feet. This distance reduces as the number of WatchDogs on the line is increased. The exact number is based on where they are along the line -- the worst case is when all of the WatchDogs are concentrated at the end. Of course the actual geographic limit of the system is only limited to where a properly maintained LAN is present. If amplifying hubs and fiber optic cable are used the LAN could easily extend for miles.
There are three components, the Kentrol Energy Miser software, the BusMaster, and the WatchDog. Each is sold separately as the configuration of any given system is unique. Additionally the software comes with two options, KENTROL ALARM and KENTROL VIDEO. To determine the cost of a given system, the number of WatchDogs, BusMasters, and the software options required needs to be resolved. Additionally, the customer must supply a suitable computer and appropriate LAN.
After the equipment is all installed a quick check is made to see that all the WatchDogs are communicating with the computer. Then the desired ‘on peak’ and ‘off peak’ temperatures are set with the calendar for each controlled space. In the case of an office or school building where there are regular hours and holidays, all zones can be set at once. If there are a few zones that are different, they can be set individually.
The computer communicates with the BusMasters continuously. Should one fail due to losing its power, being disconnected, etc., the computer will know about it in seconds. The computer will then take appropriate action – see the Alarm section below. Incidentally, if communication to the WatchDogs is lost for some reason, they will continue to hold whatever temperature they were last instructed.
The computer communicates with the WatchDogs continuously. Should one fail due to losing its power, being disconnected, etc., the computer will know about it in seconds. The computer will then take appropriate action – see the Alarm section below.
If the ultimate in dependability is desired, the computer can be continuously monitored by a special WatchDog that is designed specifically for that purpose. It is used to check the sanity of the host computer by continuously communicating with it. The Watchdog is connected to the LAN and a separate simple dialer, which calls a programmed number should the computer lockup or otherwise cease to function. Note that the dialer is a separate device, not connected or related to the KenTrol Messaging System.
Kentrol Energy Miser systems have been installed in many buildings where there is no computer system common to it. In fact, there is considerable advantage to not being connected to an existing computer system as traffic on that system or someone doing something to it that causes it to go down causes the Kentrol Energy Miser to go down as well.
If there is no computer LAN in a building, the installation is the same, except that a piece of CAT-5 cable must be run from the BusMaster(s) to the computer.
Yes, but it might not be recommended. If your building network is a standard TCP/IP protocol network and is well maintained it is certainly permissible to use it for the communication path to the control computer. If, however, the network has very heavy traffic, goes down periodically because of LAN card failure in machines, hub failure, various wiring troubles, etc. it might be better to simply run a separate CAT-5 line to the control computer to create an isolated LAN for the energy control system.
Yes it will as long as the radio LAN follows the TCP/IP protocol, but it is usually much better to put the Kentrol Energy Miser system on a hard wired network because of various dependability and security issues with radio equipment.
Some, high dependability Kentrol Energy Miser installations are done such that every component is served by UPS power. Most are not, however. It would be advisable to supply the control computer with UPS power so it can call a person for help (see Alarm section below), but even that isn’t necessary. Obviously if there is no UPS power available, or if it becomes exhausted, the system will cease to function. If temperatures are below freezing and there is no standby power source of any sort, the building is in danger of freezing as there is not only no control system functioning, but probably no heat available anyway.
When the power returns, however, the Kentrol Energy Miser system can be configured to restart and regain control of its various functions without operator intervention.
The Kentrol Energy Miser is a control system, not a heating or cooling system. In almost all cases the existing heating or cooling system can be controlled by the Kentrol Energy Miser to significant advantage. It doesn’t make any difference if the system is natural gas fired forced air, hot water boiler, steam boiler, heat pump, mechanical air conditioning, absorption air conditioning, etc. If there is an ‘ordinary’ thermostat, the Kentrol Energy Miser system can probably control the system and invoke unparalleled savings.
Yes it can. The pneumatic valves at each radiator just need to be replaced by a simple solenoid valve. The WatchDogs are connected to this new valve and the control becomes electrical instead of pneumatic. This is a common use of the KenTrol system and results in a 100 year step forward in control technology.
Yes it can. The hand or thermostatically controlled valves at each radiator simply need to be replaced by a simple solenoid valve. The WatchDogs are connected to this new valve and the control becomes electrical instead of manual. An astounding difference in the control of the heat in the building will result.
The Kentrol Energy Miser system has a feature that can help significantly with the maintenance of steam systems. The most labor intensive component in most steam systems is the steam trap at each radiator. The WatchDog has a separate input that can be used to monitor the pipe temperature just downstream of the trap. Should the trap fail and start to blow through, the Kentrol Energy Miser system will notice it and report it. Since the traps are monitored continuously, trap maintenance can be greatly reduced and no attention need be given them unless one actually fails.
In addition to the standard heat and air conditioning control WatchDog, there are five other WatchDogs that may be of interest. One is a six digital input WatchDog. . . it is particularly useful for building security systems. Up to six inputs (door switches, motion detectors, fire alarms, etc.) can be connected to this single WatchDog, and of course these devices show up on the computer screen that is running the KENTROL ALARM software via the LAN.
The second is a WatchDog that is used to check the sanity of the host computer. It is typically connected to the LAN and includes a separate simple dialer that calls its number should the computer lockup or otherwise cease to function. See the section above regarding computer failure.
The third is a special WatchDog that allows the KenTrol system to become an enthalpy based controller for use of outside air to heat or cool a building. It provides input to the computer for intelligent use of outside air, and is particularly valuable with the other parts of the KenTrol system because while the outside air may not be suitable for building conditioning during 'on peak' periods, it sometimes can be during the first part of recovery from setback.
The fourth is a WatchDog that provides KenTrol system input relative to the CO2 levels in the building. This input can then be used to admit outside air as required to limit the CO2 in the building to meet school codes, for instance; but do so without the wholesale introduction of outside air that must be conditioned at great expense.
The fifth is a WatchDog used for heat plant control. It provides important energy consumption economies based on limiting the operation of the heat plant. See the boiler control question below. In addition to the standard heat and air conditioning control WatchDog, there are two other WatchDogs that may be of interest. One is a six digital input WatchDog. . . it is particularly useful for building security systems. Up to six inputs (door switches, motion detectors, fire alarms, etc.) can be connected to this single WatchDog, and of course these devices show up on the computer screen that is running the KENTROL ALARM software via the LAN.
One of the most valuable functions of the Kentrol Energy Miser system is its ability to ‘call a person for help’. It has a very powerful messaging system that can call a predetermined list of numbers for various types of alarms, play a prerecorded message that is specific to that exact alarm cause, and await an appropriate response from the called party. That allows the system to be sure an appropriate person has been reached and that they understand the message. As the computer goes down through its list of numbers, it will await the required response from the called party. If it doesn’t get it, it will continue down its list until it does.
In this manner a called party can either give the response (by dialing a predetermined touch tone code), or simply hang up. If the called party just hangs up, others on the list will be called. . . the first called party may want to do this to insure that other help is on its way should the message be indicative of a problem the first person can’t handle by himself. If the computer hears the appropriate response, it stops dialing.
In the event that all the numbers are exhausted without the appropriate response, the computer will start at the top of the list and go through it repeatedly. The messaging system works for all alarm functions – examples are a communication failure in the BusMaster circuit, a boiler that has low water or doesn’t reach steam pressure, high water level in the condensate return tank, etc.
A separate software function is available in the system to start and stop the boiler in a hot water or steam system. This is an important energy saving segment of the system as large amounts of energy are wasted with a boiler and piping system that are held in a hot state when the building does not need heat.
The boiler control uses the PID based software function to determine when the boiler will need to be up to temperature in order to meet the first WatchDog’s call for heat. Just as the Kentrol Energy Miser learns the characteristics of each area it is controlling, it learns the characteristics of the boiler – how long it takes to get steam up, etc. Being able to keep the boiler off when it isn’t needed results in surprising savings in fuel expense.
The KENTROL ALARM is an optional software module that provides the functions of an intrusion and fire alarm. Standard alarm devices (door switches, motion detectors, fire detectors) are connected to the building’s LAN (or the stand alone KENTROL LAN) via a WatchDog. All of the functions of a commercial alarm console are handled by the same computer that runs the other KENTROL software. The same messaging system the computer uses to notify people of trouble with the energy control system is used to contact the appropriate people based on the type of alarm.
Just as the Kentrol Energy Miser and KENTROL ALARM can use a simple CAT-5 cable LAN to connect the control computer to the building heating and cooling components as well as alarm device inputs, it can also use a separate interface device to put the signal from video cameras on the same LAN. The KENTROL VIDEO software has been developed for building and plant site monitoring. It records video only when motion is present to preserve drive space. The software can show live real time video from the cameras on the screen (or multiple camera images on the screen at the same time), can rotate through the live video images, and can ‘play back’ video from the past that it has recorded. Therefore if an event was thought to have occurred over a weekend, the video for that time period could be viewed as seen by any system camera. A particularly valuable feature is that the only events recorded will be ones where there is motion. Therefore when looking for a particular activity over a weekend or other long period, only periods where something is actually changing need be viewed. This makes overnight or weekend review very practical -- practical enough that it can be practiced on a regular basis if desired. Sometimes it is quite surprising to discover what has happened when 'no one was around'. Live video can be manipulated on the console with on screen controls for pan, tilt, and zoom where PTZ cameras are used.
Kennedy Controls Corporation, P.O. Box 38 Taylorville, IL 62568
217-287-7231 (office) 217-287-7232 (fax)
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