Moisture content control system

A system for controlling moisture content in ambient airflow in a substantially enclosed structure having components. The system includes at least one humidity control apparatus and a plurality of sensors for detecting moisture content in airflow in a plurality of locations of the substantially enclosed structure. The plurality of sensors are located remotely from the at least one humidity control apparatus and are situated in relatively close proximity to the components that the at least one humidity control apparatus is configured to affect. The system also includes a controller configured to receive moisture content levels detected by one or more of the plurality of sensors and to control the at least one humidity control apparatus based upon the detected moisture content levels to vary the moisture content in the ambient airflow around the plurality of locations.

BACKGROUND

A data center may be defined as a location, for instance, a room, that houses computer systems arranged in a number of racks. A standard rack or an electronics cabinet is defined as an Electronics Industry Association (EIA) enclosure, 78 in. (2 meters) high, 24 in. (0.61 meter) wide and 30 in. (0.76 meter) deep. These racks are configured to house a number of computer systems, about forty (40) to 200 or more systems. The computer systems typically include a number of printed circuit boards (PCBs), mass storage devices, power supplies, processors, micro-controllers, and semi-conductor devices that dissipate relatively significant amounts of heat during their operation.

One or more air conditioning (AC) units are typically employed to supply cooling airflow to dissipate the heat generated by the computer systems. It is beneficial to control the moisture content in the airflow supplied by the AC units because too much moisture increases the risk of condensation forming on the computer systems and too little moisture increases the risk of electrostatic discharge issues. In order to substantially maintain the moisture content within a desired range, the AC units are often equipped with a humidifier/dehumidifier configured to add or remove moisture content in the cooling airflow. AC units equipped with these devices are also typically equipped with humidity sensors positioned at the returns to detect the relative humidity of the airflow returning into the AC units through returns. In addition, the AC units control the moisture content of the cooling airflow to meet a predetermined relative humidity set point at the returns.

If designed and arranged appropriately, and if the desired relative humidity range is broad, such as, between 20%-80%, the AC units are typically capable of maintaining the relative humidity levels within the desired range. However, because the humidity control is based only on the relative humidity detected at the returns of the AC units and because relative humidity is a function of temperature, when there is a problem, such as, if one of the AC units supplies overly cool airflow, certain areas of the data center may receive the cooler air, which may lead to the formation of condensation in those areas. In addition, the AC units may operate in relatively energy inefficient manners because one AC unit may be humidifying while another AC unit is dehumidifying in supplying cool airflow to the same areas in the data center.

It would thus be desirable to have humidity control in a structure, such as, a data center, without suffering from the drawbacks and disadvantages associated with conventional humidity control arrangements.

DETAILED DESCRIPTION

Disclosed herein are systems and methods for controlling moisture content in ambient airflow in a substantially enclosed structure. The systems and methods disclosed herein include the use of at least one humidity control apparatus and a plurality of sensors for detecting moisture content in airflow in a plurality of locations of the substantially enclosed structure. The plurality of sensors are located remotely from the at least one humidity control apparatus and are situated in relatively close proximity to the components that the at least one humidity control apparatus is configured to affect. The terms “located remotely”, as well as examples of configurations where the plurality of sensors are located remotely from the at least one humidity control apparatus are presented herein below.

Through implementation of the systems and methods disclosed herein, the humidity levels in the substantially enclosed structure may be detected at the locations where humidity control is to be provided. In addition, one or more humidity control apparatuses may be actuated to vary the humidity levels of the airflow supplied to those locations. As such, electronic components positioned at those locations may be maintained under desired environmental conditions, which may increase their reliabilities as well as increase energy efficiency in operating the one or more humidity control apparatuses.

With reference first toFIG. 1A, there is shown a simplified perspective view of a portion of a substantially enclosed structure100in which various examples of the invention may be practiced. The substantially enclosed structure100may comprise any reasonably suitable type of substantially enclosed structure, such as, a building, a room, a container, etc. As such, the terms “substantially enclosed” are intended to encompass structures whose environments may substantially be controlled. In this regard, the substantially enclosed structure100need not be completely sealed off from an outside environment, but may have some level of influence from an outside environment. In fact, air conditioning unit(s) may be configured to draw in some amount of external, makeup, airflow into the substantially enclosed structure100.

According to an example, the substantially enclosed structure100depicted inFIG. 1Acomprises a data center having computing, cooling control, and humidity control equipment. The terms “data center” are generally meant to denote a room or other space where one or more electronic components may be situated. It should be readily apparent to those of ordinary skill in the art that the substantially enclosed structure100depicted inFIG. 1represents a generalized illustration and that other components may be added or existing components may be removed or modified without departing from the scope of the invention. In addition, although particular reference is made throughout the present disclosure to the substantially enclosed structure100as comprising a data center, it should be understood that the substantially enclosed structure100may comprise other types of structures as discussed herein above.

The substantially enclosed structure100is depicted as having a plurality of racks102-108, for instance, electronics cabinets, aligned in parallel rows. Each of the rows of racks102-108is shown as containing four racks positioned on a raised floor110. A plurality of wires and communication lines (not shown) may be located in a space112beneath the raised floor110. The space112may also function as a plenum for delivery of cooled airflow from one or more air conditioning (AC) units114a-114n, where n is an integer greater than one, (only AC units114aand114bare shown) to the racks102-108. The cooled airflow may be delivered from the space112to the racks102-108through vent tiles118located between some or all of the racks102-108.

The racks102-108are generally configured to house a plurality of electronic components116, for instance, processors, micro-controllers, high-speed video cards, memories, semi-conductor devices, and the like. The electronic components116may be elements of a plurality of subsystems (not shown), for instance, computers, servers, bladed servers, etc. The subsystems and the components may be implemented to perform various electronic, for instance, computing, switching, routing, displaying, and the like, functions.

The sides of the racks102-108that face the vent tiles118may be considered as the fronts or the inlets of the racks and the sides of the racks102-108that face away from the vent tiles118may be considered as the rears or the exhausts of the racks102-108. For purposes of simplicity and not of limitation, this nomenclature will be relied upon throughout the present disclosure to describe the various sides of the racks102-108.

The AC units114a-114nare generally operated to cool received heated air as indicated by the arrows126and to supply the cooled air into the space112. Although not explicitly depicted inFIG. 1A, the AC units114a-114nmay also draw in makeup airflow externally from the substantially enclosed structure100. In various instances, the AC units114a-114ninclude devices for humidifying and/or dehumidifying the airflow prior to supplying the cooled airflow into the space112. In these instances, the AC units114a-114nmay be operated to either increase or decrease moisture levels in the airflow supplied into the space112based upon, for instance, relative humidity set points, temperature set points, or both, that the AC units114a-114nare programmed to achieve in cooling and/or humidifying the airflow. In this regard, when an AC unit114ais controlling relative humidity, an increase in temperature set point typically drives the AC unit114ainto humidification while a decrease in temperature set point typically forces the AC unit114ainto dehumidification.

Also shown inFIG. 1are humidity control apparatuses130a-130n, where n is an integer greater than one (only130aand130bare shown). Generally speaking, the humidity control apparatuses130a-130nare configured to vary the moisture content in the airflow supplied to one or more locations in the substantially enclosed structure100. In other words, the humidity control apparatuses are configured to receive airflow, vary the moisture content in the received airflow, and to output the airflow with the varied moisture content. In addition, the humidity control apparatuses130a-130nmay draw in makeup airflow externally from the substantially enclosed structure100and may vary the moisture content of the makeup airflow in addition to the airflow received from the substantially enclosed structure100.

In the example depicted inFIG. 1A, the humidity control apparatuses130a-130ncomprise separate and distinct components from the AC units114a-114n. According to other examples, however, one or more of the humidity control apparatuses130a-130nmay be integrated with the AC units114a-114nand may thus comprise the humidifying and/or dehumidifying devices discussed above. In addition, although the humidity control apparatuses130a-130nhave been depicted as being elevated from the raised floor110, the humidity control apparatuses130a-130nmay be positioned on the raised floor110and may supply airflow into the space112, similarly to the AC units114a-114n.

Either or both of the AC units114-114nand the humidity control apparatuses130a-130nmay be controlled by a controller128. In one regard, the controller128may control the AC units114a-114nto vary the temperature, humidity levels, and volume flow rates of the air supplied by the AC units114a-114n. In addition, or alternatively, the controller128may control the humidity control apparatuses130a-130nto vary the moisture content levels in the airflow supplied by the humidity control apparatuses130a-130n. The controller128is described in greater detail herein below with respect toFIG. 2.

In controlling either or both of the AC units114a-114n, the controller128may receive sensed humidity data from a plurality of humidity sensors140a-140n, where n is an integer greater than one and is not necessarily the same value as the “n” in reference numerals114n,130n, and132n, which may also differ among each other. The humidity sensors140a-140nmay comprise any reasonably suitable type of humidity sensor, such as, hygrometers, psychrometers, etc. In addition, the humidity sensors140a-140nare configured to communicate the sensed data to the controller128through any reasonably suitable manner, for instance, through a wired network, over a wireless network, etc.

The humidity sensors140a-140nare depicted as having diamond shapes to distinguish them from other features shown inFIG. 1A. In addition, the humidity sensors140a-140nare depicted as being located at various positions throughout the substantially enclosed structure100. For instance, some of the humidity sensors140a-140care depicted as being positioned along either the inlets or the outlets of the racks102-108. Another humidity sensor140dis depicted as being positioned near a vent tile118. A further humidity sensor140nis depicted as being positioned on top of a rack108. It should be understood that the humidity sensors140a-140nmay be positioned at any reasonably suitable location in the substantially enclosed structure100, so long as the humidity sensors140a-140nare located remotely from the humidity control apparatuses130a-130nand the AC units114a-114nas described in greater detail herein below.

The substantially enclosed structure100is illustrated inFIG. 1Aas containing four rows of racks102-108, two AC units114a,114b, and two humidity control apparatuses130a,130bfor purposes of simplicity and illustration. Thus, the substantially enclosed structure100should not be limited in any respect based upon the number of racks102-108, AC units114a,114b, and humidity control apparatuses130a,130billustrated inFIG. 1A. In addition, although the racks102-108have all been illustrated similarly, the racks102-108may comprise heterogeneous configurations. For instance, the racks102-108may be manufactured by different companies or the racks102-108may be designed to house differing types of electronic components116, for example, horizontally mounted servers, bladed servers, etc.

With reference now toFIG. 1B, there is shown a simplified plan view of the substantially enclosed structure100depicted inFIG. 1A. The substantially enclosed structure100is depicted as including AC units114a-114npositioned at various locations throughout the substantially enclosed structure100. A plurality of vent tiles118are also illustrated inFIG. 1Band are configured to deliver cooled airflow to the racks102-108as described above.

As described herein above, the vent tiles118and the racks102-108are positioned on a raised floor110, beneath which lies the space112(FIG. 1A). Also depicted inFIG. 1Bare humidity control apparatuses130a-130n(only130aand130bare shown). According to a first example, a single humidity control apparatus130amay be implemented to vary the moisture content in the ambient airflow contained in the substantially enclosed structure100. According to another example, a plurality of humidity control apparatuses130a-130nmay be implemented to vary the moisture content in respective areas or zones in the substantially enclosed structure100. In the latter example, the zones affected by the plurality of humidity control apparatuses130a-130nmay be made to be substantially distinct from each other, for instance, through use of partitions, airflow rates, etc, or the zones may overlap with each other.

The substantially enclosed structure100is depicted with a box formed of dotted lines132aand a box formed of dashed lines132b, which represent zones respectively associated with the humidity control apparatuses130aand130b. The respective zones132aand132bmay be identified based upon the proximities of the humidity sensors140a-140nto respective humidity control apparatuses130a-130n. In addition, or alternatively, the respective zones132aand132bmay be identified through a commissioning process, which is described in greater detail herein below. The identification of the zones132aand132bmay result in some or all of the humidity sensors140a-140nbeing contained in multiple zones132aand132bas shown inFIG. 1B. The zones132aand132bhave been depicted as having rectangular shapes for purposes of simplicity only and it should therefore be understood that the zones132aand132bmay be identified as having any reasonably suitable shape based upon, for instance, implementation of a commissioning process discussed below.

Also disclosed in greater detail herein below are various manners in which the humidity control apparatuses130a-130nmay be controlled by the controller128based upon input received from the humidity sensors140a-140n, which are illustrated as being positioned at various locations with respect to the racks102-108and other components in the substantially enclosed structure100.

Turning now toFIG. 2, there is shown a simplified block diagram of a system200for controlling moisture content in ambient airflow in a substantially enclosed structure, according to an example. It should be understood that the system200may include additional elements and that some of the elements described herein may be removed and/or modified without departing from the scope of the system200. In addition, the system200is described as including many of the components discussed above with respect to the substantially enclosed structure100depicted inFIGS. 1A and 1B. It should, however, be understood that the system200may be employed in an environment that differs from the those depicted inFIGS. 1A and 1B

As shown, the system200includes the controller128, which may comprise software, firmware, or hardware. The controller128is depicted as including an input module210, a commissioning module212, a humidity control module214, and a cooling control module216. The commissioning module212and the cooling control module216may be considered as optional modules for the controller128because these modules may not be implemented in every embodiment of the system200. Instead, the commissioning module212and the cooling control module216may be implemented in various embodiments as discussed herein below.

In instances where the controller128comprises software, the controller128may be stored on a computer readable storage medium and may be executed by the processor of a computing device, such as one of the electronic components116depicted inFIG. 1A. In these instances, the modules210-216may comprise software modules or other programs or algorithms configured to perform the functions described herein below. In instances where the controller128comprises firmware or hardware, the controller128may comprise a circuit or other apparatus configured to perform the functions described herein. In these instances, the modules210-216may comprise one or more of software modules and hardware modules.

Thus, by way of example, the controller128may comprise a processor of a computing device and the modules210-216may comprise software stored on a computer readable storage medium. The computer readable storage medium may comprise the data store220or a separate storage device. In addition, the data store220may comprise volatile and/or non-volatile memory, such as DRAM, EEPROM, MRAM, flash memory, and the like. In addition, or alternatively, the data store220may comprise a device configured to read from and write to a removable media, such as, a floppy disk, a CD-ROM, a DVD-ROM, or other optical or magnetic media.

In any regard, the controller128may be executed or implemented to control moisture content in ambient airflow in a substantially enclosed structure100, such as, a building, a room, a data center, etc. More particularly, for instance, the controller128may be executed or implemented to substantially maintain moisture content levels in the ambient airflow within a predefined range. Various examples of manners in which the controller128may control moisture content are described herein below.

The controller128may implement or execute the input module210to receive input from a plurality of sensors140a-140nconfigured to detect moisture content in airflow. The controller128may also execute the input module210to receive input from a makeup air sensor202positioned to detect the moisture content in the makeup air brought into the substantially enclosed structure100from the external environment. The controller128may store the data received from the plurality of sensors140a-140nand the makeup air sensor202in the data store220. As shown inFIG. 1A, the sensors140a-140nare positioned at various locations throughout the substantially enclosed structure100. More particularly, for instance, the sensors140a-140nare positioned at various locations where the moisture content levels are to be controlled. By way of particular example, the sensors140a-140nmay be positioned at the inlets/outlets of the racks102-108containing the electronic components116. In this regard, the sensors140a-140nare positioned remotely from the humidity control apparatuses.

Although not shown, the input module210may also be configured to receive input from a plurality of other types of sensors, such as temperature sensors, pressure sensors, etc. According to an example, the controller128may utilize the input from the other types of sensors in controlling the AC units114a-114n.

The controller128may implement or execute the commissioning module212to implement a commissioning process designed to identify which of a plurality of humidity control apparatuses130a-130nvaries moisture content in the airflow supplied to which of the one or more zones132a-132nin the substantially enclosed structure100. In addition, or alternatively, the commissioning module212may be implemented to determine which of the humidity control apparatuses130a-130nvaries moisture content to at least a predefined level and may identify the one or more zones132a-132nbased upon that determination.

The commissioning module212is considered to be optional because a commissioning process may not be required for every substantially enclosed structure100employing the system200. For instance, the commissioning module212may be omitted in instances where the substantially enclosed structure100contains a single humidity control apparatus130a. As another example, the commissioning module212may be omitted in instances where the controller128is configured to operate a plurality of humidity control apparatuses130a-130nas a group.

The controller128is configured to implement or execute the humidity control module214to control the humidity control apparatuses130a-130n. The controller128may implement or execute the humidity control module214in various manners as discussed herein below based upon, for instance, the configuration of the substantially enclosed structure100.

The controller128is further configured to implement or execute the cooling control module216to control one or more of the AC units114a-114n, as also described in greater detail herein below. The cooling control module216may be considered to be optional because control of the AC units114a-114nmay be performed by another controller or each of the AC units114a-114nmay operate substantially independently with respect to each other.

According to an example, the humidity control apparatuses130a-130nare physically separate from the AC units114a-114n. In this example, the humidity control apparatuses130a-130nmay be operated separately from the AC units114a-114n. In other words, operations of the AC units114a-114nare not intended to directly affect operations of the humidity control apparatuses130a-130nor vice versa.

According to another example, at least one of the humidity control apparatuses130a-130nis integrated with at least one of the AC units114a-114n. In this example, the controller128may control both the integrated AC unit114aand humidity control apparatus130ain various manners to substantially optimize energy efficiency. By way of example, the controller128may control the integrated AC unit114aand humidity control apparatus130a, such that, when the integrated AC unit114ais actively cooling, the humidity control apparatus130ais not actively humidifying. Likewise, the controller128may control the integrated AC unit114aand the humidity control apparatus130a, such that, when the integrated AC unit114ais actively heating, the humidity control apparatus130ais not actively dehumidifying.

The controller128may implement a commissioning process to identify regions of influence for each of the AC units114a-114n. A suitable commissioning process is disclosed in commonly assigned U.S. Pat. No. 7,117,129, filed on Mar. 11, 2005, and entitled “Commissioning of Sensors”, the disclosure of which is hereby incorporated by reference in its entirety. In implementing the commissioning process, the controller128may determine that one or more of the AC units114a-114nhave regions of influence that substantially overlap with the regions of influence of one or more other AC units114a-114n.

The controller128may determine which of the plurality of AC units114a-114nhave humidity control apparatuses130a-130n, and that control a particular region, should be used for a particular type of humidity control given the state of temperature control of the AC units114a-114nin the potential pool of AC units114a-114nthat control the particular region. By way of example, to dehumidify a particular region, the controller128may utilize the AC unit114athat is operating at the lowest temperature as compared with a different AC unit114bbecause the act of dehumidifying requires low temperature air, thus making this option more energy efficient than that of choosing the AC unit114bthat is supplying relatively higher temperature air.

Examples of methods in which the system200may be employed to control moisture content in ambient airflow in the substantially enclosed structure100will now be described with respect to the following flow diagram of the method300depicted inFIG. 3. It should be apparent to those of ordinary skill in the art that the method300represents a generalized illustration and that other steps may be added or existing steps may be removed, modified or rearranged without departing from the scopes of the method300.

The description of the method300is made with reference to the system200illustrated inFIG. 2, and thus makes reference to the elements cited therein. It should, however, be understood that the method300is not limited to the elements set forth in the system200. Instead, it should be understood that the method300may be practiced by a system having a different configuration than that set forth in the system200.

The controller128may implement or execute one or more of the modules210-216to perform the method300in controlling the moisture content in ambient airflow of the substantially enclosed structure100.

FIG. 3, more particularly, shows a flow diagram of a method300of controlling moisture content in ambient airflow in a substantially enclosed structure100with at least one humidity control apparatus130a, according to an example. As shown, moisture content or humidity, either relative humidity or absolute humidity, is detected at a plurality of locations in a substantially enclosed area100with a plurality of humidity sensors140a-140n, as indicated at step302.

As discussed above with respect toFIG. 1A, the humidity sensors140a-140nare located remotely from the at least one humidity control apparatus130a-130n. In addition, in instances where a plurality of humidity control apparatuses130a-130nare employed in the system200, the humidity sensors140a-140nare also located remotely from each of the plurality of humidity control apparatuses130a-130n. The humidity sensors140a-140nare considered to be “located remotely” from the humidity control apparatuses130a-130nbecause the humidity sensors140a-140nare not located in close proximity to the humidity control apparatuses130a-130n. In other words, the “located remotely” may be defined to include that the humidity sensors140a-140nare located sufficiently distant from the humidity control apparatuses130a-130n, such that, one or more environmental conditions may differ between the locations of the humidity control apparatuses130a-130nand the humidity sensors140a-140n. In addition, or alternatively, the “located remotely” may be defined to include that the humidity sensors140a-140nare located in positions in the substantially enclosed structure100where the humidity control apparatuses130a-130nare configured to vary the moisture content in the airflow supplied by the humidity control apparatuses130a-130n. Thus, for instance, the “located remotely” may be defined to include that the humidity sensors140a-140nare placed in any location from which air is received into the racks102-108. These locations may include, for instance, at the inlets of the racks102-108, in the space112, in aisles containing vent tiles118, etc.

At step304, the controller128receives data pertaining to the moisture content detected by the humidity sensors140a-140n. The controller128may process the data to determine whether the moisture content levels at the one or more locations are within a predefined moisture content range, as indicated at step306. The predefined moisture content range may comprise an acceptable moisture content range for the components116positioned at the one or more locations, for instance, as set forth by the component116manufacturers, as identified through testing, as set forth in one or more standards, such as ASHRAE, etc. By way of example, the predefined range may be between about 20 to 80 percent. As another example, the predefined range may be between about 40 to 55 percent. The predefined range may depend, for instance, upon the sensitivities of the components116to moisture levels in the air.

According to an example, based upon the detected moisture content data received from the humidity sensors140a-140n, the controller128may identify which areas in the substantially enclosed area100have moisture content levels that are within the predefined range and which areas have moisture content levels that are outside of the predefined range, at step306. In this example, the controller128may determine which of the humidity control apparatuses130a-130nis operable to vary the moisture content in the airflow contained in the various areas. An example of a manner in which the controller128may commission the humidity control apparatuses130a-130nto identify their respective zones of influence is described herein below with respect toFIG. 4.

In any regard, for those areas where the moisture content is determined to be within the predefined range, which may include the entire area of the substantially enclosed structure100, the controller128may not vary operations of the humidity control apparatuses130a-130n. In addition, the moisture content at the plurality of locations may be detected again at step302and steps304and306may be repeated. However, for those areas where the moisture content is determined to be outside of the predefined range, which may again include the entire area of the substantially enclosed structure100, the controller128may vary operations of one or more of the humidity control apparatuses130a-130nthat are operable to affect those areas, as indicated at step308.

More particularly, at step308, the controller128may vary operations of the one or more humidity control apparatuses130a-130nby causing the one or more humidity control apparatuses130a-130nto either increase or decrease the moisture content level in the airflow supplied to those areas. The one or more humidity control apparatuses130a-130nmay be controlled to increase moisture content in the airflow in response to the moisture content falling below the predefined range and to decrease moisture content in the airflow in response to the moisture content exceeding the predefined range.

In addition, once the operations of the one or more humidity control apparatuses130a-130nhave been varied at step308, the moisture content at the plurality of locations may be detected again at step302and steps304-308may be repeated in a substantially continuous manner to enable the moisture content to be continuously monitored and adjusted.

According to another example in which airflow from the external environment is brought into the substantially enclosed structure100, at step302, the moisture content or humidity, either relative humidity or absolute humidity, of the airflow from the external environment is detected in addition to the moisture content at the plurality of locations. In addition, at step304, the controller128receives data pertaining to the moisture content detected by the makeup air sensor202. Furthermore, the controller128may consider the moisture content of the airflow received from the external environment in varying the operations of the one or more humidity control apparatuses130a-130nat step308. By way of example, if the moisture content in the airflow received from the external environment is relatively high and the amount of the air received from the external environment is relatively significant, the controller128may operate the one or more humidity control apparatuses130a-130nrelatively close to higher limits of humidity.

As another example, if the moisture content in the airflow received from the external environment is relatively high and the amount of the air received from the external environment is relatively significant, and the moisture content detected by the humidity sensors140a-140nis below the predefined range at step306, the controller128may cause a greater amount of airflow from the external environment to be brought into the substantially enclosed area100. In addition, the controller128may vary in the amount of airflow brought into the substantially enclosed area100based upon the amount of humidity contained in the external environment. In one regard, the one or more humidity control apparatuses130a-130nmay be operated to consume relatively lesser amounts of energy by relying more heavily upon moisture content in the airflow brought in from the external environment to meet, for instance, OSHA or ASHRAE requirements.

With reference now toFIG. 4, there is shown a flow diagram of a method400of commissioning the humidity control apparatuses130a-130nand the sensors140a-140nto identify zones of influence132a-132nfor each of the humidity control apparatuses130a-130n. It should be apparent to those of ordinary skill in the art that the method400represents a generalized illustration and that other steps may be added or existing steps may be removed, modified or rearranged without departing from the scopes of the method400.

The controller128may implement or execute the commissioning module212to perform the method400to identify which zones132a-132nin the substantially enclosed structure100each of the humidity control apparatus130a-130nrespectively has at least a predetermined level of influence. Once the respective zones132a-132nhave been identified, each of the sensors140a-140nmay be associated with one or more of the humidity control apparatuses130a-130nbased upon which of the zones132a-132nthe sensors140a-140nare located. That is, those sensors140a-140ncontained in a particular zone132aare considered to be associated with the humidity control apparatus130athat is associated with the particular zone132a.

Generally speaking, in the method400, each of the humidity control apparatuses130a-130nis independently perturbed at different times, such as, in a sequential manner, by either injecting moisture into or removing moisture from the airflow supplied by the humidity control apparatuses130a-130n. The responses of the humidity sensors140a-140nto the perturbations are measured and recorded as a function of time. Those humidity sensors140a-140nrecording a rate of change of moisture greater than a predefined threshold are considered to reside within that humidity control apparatus' zone132a-132n.

More particularly, at step402, the controller128may set the humidity control apparatuses130a-130nto a first level. The first level may include, for instance, a humidity output level that is common to all of the humidity control apparatuses130a-130n. The controller128may wait for a period of time at step404prior to recording humidity measurements obtained by the humidity sensors140a-140nat step406. The controller128may allow this time period to elapse in order to enable a relatively steady-state of operation to be reached. In addition, during the time period at step406, the controller128may determine a median humidity reading for one or more of the humidity sensors140a-140nin the event that the humidity levels detected by one or more of the humidity sensors140a-140noscillate during the time period. In this case, the humidity measurements recorded at step406may comprise time-averaged values.

At step408, the controller128may control a humidity control apparatus130ato change the moisture content in the airflow by a specified amount. The specified amount may comprise an amount that differs from the first level moisture content by a relatively discernable amount. The controller128may again wait for a period of time at step410, prior to recording humidity information received from the humidity sensors140a-140nat step412. The controller128may allow this time period to elapse in order to enable a relatively steady-state of operation to be reached following the moisture content change in the airflow supplied by one of the humidity control apparatuses130a. In addition, during the time period at step410, the controller128may determine a median humidity reading for one or more of the humidity sensors140a-140nin the event that the humidity levels detected by one or more of the humidity sensors140a-140noscillate during the time period. In this case, the humidity measurements recorded at step412may comprise time-averaged values.

In any regard, at step414, the controller128may determine the levels to which the humidity measurements have changed at the humidity sensor140a-140nlocations from the humidity measurements recorded at step412. More particularly, for instance, the controller128may compare the humidity measurements recorded at step406with those recorded at step412to determine whether there have been discernable changes in the humidity levels and to what degree the changes have occurred.

At step416, the controller128identifies the zone of influence of the humidity control apparatus130athat was perturbed at step408. The controller128may make this determination based upon the degrees to which the humidity levels have changed as detected by the humidity sensors140a-140n. By way of example, the controller128may calculate humidity correlation indices (HCIs) for the humidity control apparatuses130a-130n. The HCI for a humidity control apparatus130aand a humidity sensor140amay be defined as the change in humidity detected by the humidity sensor140afollowing a change in humidity of the airflow supplied by the humidity control apparatus130a.

The controller128may also identify which of the humidity sensors140a-140ndetected changes in humidity levels that exceed a predefined level. The predefined level may be set based upon any of a number of various factors, such as, the sensitivity levels of each the humidity sensors140a-140n, the distribution of the identified zones132a-132n, etc. In addition, the locations of the humidity sensors140a-140nwhose detected humidity levels have changed beyond the predefined level may be identified as the zone132aassociated with that humidity control apparatus130a.

According to an example, the method400may be performed during actual operations of the humidity control apparatuses130a-130ninstead of as a separate operation, to identify which zones132a-132nin the substantially enclosed structure100each of the humidity control apparatuses130a-130nrespectively has at least a predetermined level of influence. In this example, the method400may be implemented in instances where the humidity control apparatuses130a-130nare not sufficiently varying humidity levels to enable adequate readings during normal operations.

A more detailed description of various manners in which the zones of influence132a-132nfor various actuators may be identified based upon sensor measurements may be found in U.S. Pat. No. 7,117,129.

At step418, the controller128records the correlation between the humidity sensors140a-140ncontained in the identified zone of influence132aand the humidity control apparatus130a. In other words, the controller128records that the humidity control apparatus130ahas at least a predefined level of influence over their correlated humidity sensors140a-140n, and thus, at least a predefined level of influence over the respective locations of the correlated humidity sensors140a-140n.

At step420, the controller128determines whether the method400should be repeated for another humidity control apparatus130b. If it is determined that an additional correlation between the another humidity control apparatus130band the humidity sensors140a-140nare to be determined, the humidity levels in the airflow supplied by the humidity control apparatuses130a-130nmay again be set to the first level at step402. Following step402, the controller128may again wait for a period of time at step404, prior to recording humidity information received from the humidity sensors140a-140nat step406, as described above. In addition, the controller128may repeat steps402-420to identify and record correlations between the humidity control apparatuses130a-130nand the humidity sensors140a-140n. The method400may end, as indicated at step422, once the controller128determines that there are no further humidity control apparatuses130a-130nremaining to be commissioned.

According to an example, instead of waiting for the periods of time to enable the conditions at the humidity sensors140a-140nto reach steady-state conditions at steps404and410, changes in the humidity measurements may be recorded at steps406and412as functions of time. In this example, at steps406and412, the change in humidity (dH) as a function of a change in time (dt) may be measured, for instance, as dH/dt. In addition, correlations between the humidity control apparatuses130a-130nand the humidity sensors140a-140nmay be made based upon whether the dH/dt measurements for the humidity sensors140a-140nexceed a predetermined dH/dt threshold at step414. The correlations may be used to identify the zones of influence for each of the humidity control apparatuses130a-130nat step416.

Through implementation of the method400and alternate examples discussed above, the controller128may relatively quickly identify which of the humidity control apparatuses130a-130nto actuate in response to a determination that the moisture content level in one or more locations of the substantially enclosed structure100is outside of a predefined humidity range. Because some of the zones132a-132nmay overlap with each other, there may arise instances where one or more of the humidity sensors140a-140nreside in more than one of the zones132a-132n. As such, the controller128may select from a plurality of humidity control apparatuses130a-130nin varying the humidity levels at the humidity sensors140a-140nin the overlapping zones132a-132n.

According to an example, the controller128may randomly select one or more of the humidity control apparatuses130a-130nto actuate when one or more of the humidity sensors140a-140nis outside of the predefined humidity range. According to another example, the controller128may select all of the humidity control apparatuses130a-130nhaving a predefined level of influence over the one or more humidity sensors140a-140nin the zone132ato actuate when the one or more of the humidity sensors140a-140nare outside of the predefined humidity range. According to a further example, the controller128may select the humidity control apparatus130ahaving the greatest margin within which to vary humidity levels. In any of these examples, when multiple humidity control apparatuses130a-130nare actuated, each of the multiple humidity control apparatuses130a-130nmay be actuated to a level that is relatively lower than would be performed with a single humidity control apparatus130a.

In instances where multiple humidity control apparatuses130a-130nare able to affect the same humidity sensors140a-140n, there is a potential for fighting among the humidity control apparatuses130a-130n. More particularly, for instance, one of the humidity control apparatuses130amay currently be adding moisture content into the airflow based upon the humidity level detected by a humidity sensor140a(located in zone132a), another of the humidity control apparatuses130bmay currently be removing moisture content from the airflow based upon the humidity level detected by a humidity sensor140b(located in zone132b), and a further sensor140cmay be located in both zones132aand132bof the humidity control apparatuses130aand130b. In this example, if the humidity sensor140cdetects a humidity level that is below the predefined level, the controller128may determine which of the humidity control apparatuses130aand130bto actuate in order to substantially prevent the humidity control apparatuses130aand130bfrom consuming excess energy in both humidifying and dehumidifying the location at which the humidity sensor140cis located.

More particularly, for instance, the controller128may implement the commissioning module212to identify control sensors for each of the zones132a-132n. The control sensors may be defined as the humidity sensors140a-140nwith the largest positive humidity difference from a set point humidity in each of the zones132a-132n. If all of the humidity sensors140a-140nhave negative humidity differences from the set point humidity, then the control sensor for a particular zone132a-132nis the humidity sensor140a-140nwith the largest negative difference from the set point humidity. The set point humidity used to determine the control sensor may vary between the humidity sensors140a-140nand is thus not required to be identical for all of the humidity sensors140a-140n.

In general, the controller128is configured to control the humidity control apparatuses130a-130nto modify the humidity levels in the zones132a-132nbased upon the humidity levels of the control sensors. As such, in the example above, the controller128may control either or both of the humidity control apparatus130aand the humidity control apparatus130bbased upon the humidity level detected by the humidity sensor140cif the humidity sensor140cis the control sensor for either or both of the humidity control apparatuses130aand130b. If the humidity sensor140cis not a control sensor for either of the zones132aor132b, the controller128may continue to operate the humidity control apparatuses130aand130bbased upon the detected humidity information the control sensors in their respective zones132aand132b.

A more detailed discussion of control sensors, actuators, and actuator families and various manners in which they are identified, controlled, and modified are discussed in U.S. Pat. No. 7,117,129 and in commonly owned and co-pending U.S. patent application Ser. No. 11/089,608 (Attorney Docket No. 200500812-1), filed on Mar. 25, 2005, and entitled “Temperature Control Using a Sensor Network”, the disclosures of which is hereby incorporated by reference in its entireties.

According to a further example, the controller128may also control a plurality of AC units114a-114nto operate in manners that substantially minimizes energy waste in terms of humidity control. More particularly, for instance, the controller128may control the plurality of AC units114a-114nto substantially prevent them from operating at cross purposes, which results in wasted energy. Typically, the AC units114a-114nequipped with humidifiers/dehumidifiers operate by dehumidifying airflow when they are cooling and by humidifying airflow when they are heating airflow. Thus, the AC units114a-114nmay be considered as operating at cross purposes when, for instance, the AC units114a-114nare heating up and de-humidifying the airflow or when they are cooling and humidifying the airflow.

In order to substantially avoid this problem, the controller128is configured to identify the zones132a-132nover which the AC units114a-114nhave a predefined level of influence, as discussed above with respect to the commissioning of the humidity control apparatuses130a-130nand the sensors140a-140n. In zones132a-132nthat overlap each other, the controller128is configured to control the AC units114a-114n, such that, if a particular zone132arequires both cooling and humidification, one of the AC units114ais used to cool the airflow and another of the AC units114bis used to humidify the airflow. In this regard, the AC units114a-114nmay be operated in manners that substantially avoid the cross-purposes discussed above while substantially maintaining desired conditions.

Some or all of the operations set forth in the methods300and400may be contained as utilities, programs, or subprograms, in any desired computer accessible medium. In addition, the methods300and400may be embodied by computer programs, which can exist in a variety of forms both active and inactive. For example, they may exist as software program(s) comprised of program instructions in source code, object code, executable code or other formats. Any of the above may be embodied on a computer readable medium, which include storage devices and signals, in compressed or uncompressed form.

Exemplary computer readable storage devices include conventional computer system RAM, ROM, EPROM, EEPROM, and magnetic or optical disks or tapes. Exemplary computer readable signals, whether modulated using a carrier or not, are signals that a computer system hosting or running the computer program can be configured to access, including signals downloaded through the Internet or other networks. Concrete examples of the foregoing include distribution of the programs on a CD ROM or via Internet download. In a sense, the Internet itself, as an abstract entity, is a computer readable medium. The same is true of computer networks in general. It is therefore to be understood that any electronic device capable of executing the above-described functions may perform those functions enumerated above.

FIG. 5illustrates a block diagram of a computing apparatus500configured to implement or execute the controller128depicted inFIGS. 1A and 2, according to an example. In this respect, the computing apparatus500may be used as a platform for executing one or more of the functions described hereinabove with respect to the controller128.

The computing apparatus500includes a processor502that may implement or execute some or all of the steps described in the methods300and400. Commands and data from the processor502are communicated over a communication bus504. The computing apparatus500also includes a main memory506, such as a random access memory (RAM), where the program code for the processor502, may be executed during runtime, and a secondary memory508. The secondary memory508includes, for example, one or more hard disk drives510and/or a removable storage drive512, representing a floppy diskette drive, a magnetic tape drive, a compact disk drive, etc., where a copy of the program code for the methods300and400may be stored.

The removable storage drive510reads from and/or writes to a removable storage unit514in a well-known manner. User input and output devices may include a keyboard516, a mouse518, and a display520. A display adaptor522may interface with the communication bus504and the display520and may receive display data from the processor502and convert the display data into display commands for the display520. In addition, the processor(s)502may communicate over a network, for instance, the Internet, LAN, etc., through a network adaptor524.

It will be apparent to one of ordinary skill in the art that other known electronic components may be added or substituted in the computing apparatus500. It should also be apparent that one or more of the components depicted inFIG. 5may be optional (for instance, user input devices, secondary memory, etc.).

What has been described and illustrated herein is a preferred embodiment of the invention along with some of its variations. The terms, descriptions and figures used herein are set forth by way of illustration only and are not meant as limitations. Those skilled in the art will recognize that many variations are possible within the scope of the invention, which is intended to be defined by the following claims—and their equivalents—in which all terms are meant in their broadest reasonable sense unless otherwise indicated.