WO2020204916A1 - Data acquisition system including nodes and a hub - Google Patents

Abstract

A data acquisition system includes a hub including a plurality of wired connections, each connection connected to one of a plurality of nodes that includes at least one sensor, each wired connection operable to deliver measured data from the sensors. A processor is operable to analyze the measured data of one of the plurality of nodes and to generate analyzed data indicative of the measured data collected by each of the sensors and a data compressor is coupled to and partially defines the hub. The data compressor is operable to compress the analyzed data. A transmitter is coupled to and partially defines the hub and is operable to transmit the compressed analyzed data.

Description

DATA ACQUISITION SYSTEM INCLUDING NODES AND A HUB

TECHNICAL FIELD

[0001] The present disclosure is directed, in general, to a data acquisition system, and more specifically to a data acquisition system including a plurality of nodes that receive sensor data and transmit that data to a single hub.

BACKGROUND

[0002] Data acquisition in large industrial machines such as steam turbines can be difficult do to the operating environment. Sensors can be difficult if not impossible to repair or replace during operation, thereby requiring redundant sensors. Providing additional sensors can be very expensive and challenging as it is difficult to provide wired connections and power to all the necessary hardware including the sensors and any transmission equipment.

SUMMARY

[0003] A data acquisition system includes a hub including a plurality of wired connections, each connection connected to one of a plurality of nodes that includes at least one sensor, each wired connection operable to deliver measured data from the sensors. A processor is operable to analyze the measured data of one of the plurality of nodes and to generate analyzed data indicative of the measured data collected by each of the sensors and a data compressor is coupled to and partially defines the hub. The data compressor is operable to compress the analyzed data. A transmitter is coupled to and partially defines the hub and is operable to transmit the compressed analyzed data.

[0004] In another construction, a data acquisition system includes a plurality of nodes, each node including a plurality of sensors each positioned to measure the same single parameter and output measured data. A hub includes a plurality of connectors arranged to connect to one of the plurality of nodes to provide communication therebetween. A processor is positioned between one of the plurality of nodes and the hub and is operable to receive the measured data from each of the sensors of at least one node, to analyze the measured data, and to generate analyzed data indicative of the single parameter measured by the plurality of sensors. An ethemet connection is coupled to and partially defines the hub. The ethernet connection is arranged to interconnect the processor and an external network and to provide electrical power to the hub. A transmitter is coupled to and partially defines the hub. The transmitter is arranged to transmit data to the external network. A selector is coupled to and partially defines the hub. The selector is operable to select one of the ethernet connection and the transmitter to transmit the analyzed data to the external network.

[0005] In another construction, a data acquisition system includes a plurality of nodes, each node including a plurality of sensors each positioned to measure the same single parameter and output measured data and a hub including a plurality of connectors, each connector arranged to connect to one of the plurality of nodes to provide communication therebetween. A processor is coupled to and partially defines the hub. The processor is operable to receive the measured data from each node, to analyze the measured data, and to generate analyzed data indicative of the single parameter measured by the plurality of sensors for each node. A transmitter is coupled to and partially defines the hub. The transmitter is coupled to the processor and is operable to transmit the analyzed data for each node, wherein each transmission includes one data packet for each of the plurality of nodes, and wherein each data packet is transmitted at a rate of at least once per second and the hub consumes on average less than 50 mW during the transmission. A battery is coupled to and partially defines the hub. The battery is operable to provide power to the processor and the transmitter and a solar panel is operable to selectively charge the battery.

[0006] The foregoing has outlined rather broadly the technical features of the present disclosure so that those skilled in the art may better understand the detailed description that follows.

Additional features and advantages of the disclosure will be described hereinafter that form the subject of the claims. Those skilled in the art will appreciate that they may readily use the conception and the specific embodiments disclosed as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Those skilled in the art will also realize that such equivalent constructions do not depart from the spirit and scope of the disclosure in its broadest form. [0007] Also, before undertaking the Detailed Description below, it should be understood that various definitions for certain words and phrases are provided throughout this specification and those of ordinary skill in the art will understand that such definitions apply in many, if not most, instances to prior as well as future uses of such defined words and phrases. While some terms may include a wide variety of embodiments, the appended claims may expressly limit these terms to specific embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Fig. 1 is a longitudinal cross section of a steam turbine including a data acquisition system.

[0009] Fig. 2 is a schematic illustration of the data acquisition system of Fig. 1 including a plurality of nodes and a hub.

[0010] Fig. 3 is a perspective view of the hub of Fig. 2.

[0011] Fig. 4 is a graphical illustration of four different operating situations.

[0012] Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

DETAIFED DESCRIPTION

[0013] Various technologies that pertain to systems and methods will now be described with reference to the drawings, where like reference numerals represent like elements throughout.

The drawings discussed below, and the various embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged apparatus. It is to be understood that functionality that is described as being carried out by certain system elements may be performed by multiple elements. Similarly, for instance, an element may be configured to perform functionality that is described as being carried out by multiple elements. The numerous innovative teachings of the present application will be described with reference to exemplary non-limiting embodiments.

[0014] Also, it should be understood that the words or phrases used herein should be construed broadly, unless expressly limited in some examples. For example, the terms“including,” “having,” and“comprising,” as well as derivatives thereof, mean inclusion without limitation.

The singular forms“a”,“an” and“the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Further, the term“and/or” as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. The term“or” is inclusive, meaning and/or, unless the context clearly indicates otherwise. The phrases“associated with” and“associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like.

[0015] Also, although the terms "first", "second", "third" and so forth may be used herein to refer to various elements, information, functions, or acts, these elements, information, functions, or acts should not be limited by these terms. Rather these numeral adjectives are used to distinguish different elements, information, functions or acts from each other. For example, a first element, information, function, or act could be termed a second element, information, function, or act, and, similarly, a second element, information, function, or act could be termed a first element, information, function, or act, without departing from the scope of the present disclosure.

[0016] In addition, the term "adjacent to" may mean: that an element is relatively near to but not in contact with a further element; or that the element is in contact with the further portion, unless the context clearly indicates otherwise. Further, the phrase“based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise. Terms“about” or“substantially” or like terms are intended to cover variations in a value that are within normal industry manufacturing tolerances for that dimension. If no industry standard as available a variation of 20 percent would fall within the meaning of these terms unless otherwise stated.

[0017] Fig. 1 illustrates a steam turbine 10 of the type used in large power generation facilities. The illustrated turbine 10 includes a high pressure (HP) section 15, an intermediate pressure (IP) section 20, and two low pressure (LP) sections 25 that each include a rotor 30 positioned to rotate about a common axis. The rotors 30 are supported for rotation by bearings 35 at each end of the turbine 10 and between each section 15, 20, 25. Typically, a generator (not shown) is connected to the steam turbine 10 and includes a rotor supported for rotation by a pair of bearings. The steam turbine 10 receives high pressure, high temperature steam at an inlet to the HP section 15 and expands that steam to generate torque that is converted to electrical power by the generator. In the illustrated steam turbine 10, the steam exits the HP section 15 and returns to a boiler or other heat source where the steam is reheated. The reheated steam is then directed to the IP section 20 of the steam turbine 10 where the steam is further expanded, and additional torque is generated. The steam then flows to the two LP sections 25 for final expansion and discharge into a condenser or other cooling apparatus. Often, steam is extracted at various points within the turbine 10 for use in preheating water that is being directed to the boiler or for other purposes.

[0018] As one of ordinary skill in the art will understand, there are many different turbine designs and arrangements. In addition, there are many different heat sources beyond a boiler that are possible. The steam turbine 10 of Fig. 1 is simply provided as one of many possible examples. In addition, the devices and methods described herein are applicable to other turbines including gas turbines, wind turbines, hydro turbines and the like or other devices or systems.

[0019] During operation of the turbine 10 of Fig. 1 , operators monitor various parameters to assure correct and efficient operation. For example, sensors 45 are positioned throughout the turbine 10 and the bearings 35 to measure vibration levels. Additional sensors 45 are positioned to measure things like oil temperature, oil pressure, steam temperature, steam pressure, metal temperatures, flow rates, valve positions, extraction temperatures, and the like. In a typical steam turbine 10, dozens of sensors 45 are positioned to measure dozens of data points. This data is typically logged, and for some data points actively monitored. Alarms are often provided to warn operators when measured data points fall outside of expected ranges.

[0020] Often, sensors 45 are located in difficult to reach locations. These locations can be particularly difficult to reach, or even impossible to reach while the steam turbine 10 is operating. In view of these difficulties, multiple redundant sensors 45 are often positioned with each sensor 45 taking the same measurement. Prior systems might connect to only one or two of the redundant sensors 45 leaving the others as potential spares should one of the connected sensors 45 fail.

[0021] With continued reference to Fig. 1 , a data acquisition system 50 includes multiple sensors 45 positioned to measure various data points with each measurement being fed to a node 55.

Each node 55 is in turn connected to a hub 60 to complete the data acquisition system 50.

[0022] Fig. 2 schematically illustrates one arrangement of the data acquisition system 50 including a plurality of redundant sensors 45, a plurality of sensor nodes 55, and a hub 60. The illustrated construction includes five sensors 45 positioned to measure one parameter of the turbine 10 (e.g., a bearing temperature). Each of the sensors 45 measures the desired parameter and sends that data to one of the nodes 55. In most constructions, the sensors 45 include a wired connection to the node 55, with wireless transmission being possible. Fig. 2 illustrates seven individual nodes 55 with fewer or more being possible. Each node 55 is arranged to gather sensor data from all the sensors 45 measuring a single particular parameter (e.g., a bearing temperature, a steam pressure, a vibration level, a valve position, etc.). Thus, one node 55 may measure and report a bearing temperature, with another node 55 measuring and reporting bearing vibration. Still other nodes 55 might report the temperature of the steam entering the HP section 15 or exiting the HP section 15. Fig. 2 illustrates only one node 55 connected to sensors 45, however it should be understood that each node 55 is connected to one or more sensors 45.

[0023] Each node 55 may include a processor 65, a memory device 70, and a transmission device 75 to transmit data to the hub 60. The processor 65 may include a program that analyzes the measured data from each sensor 45 to determine if one or more of the sensors 45 is providing incorrect or bad data. If one or more of the sensors 45 is providing bad data, the sensor 45 or sensors 45 are ignored, and a message can be provided to the operator to identify the failed sensor 45 or sensors 45. The processor 65 then analyzes the remaining sensor values to determine the actual measurement. In some constructions, a simple average is employed with other nodes 55 possibly including more complex analysis schemes. Once complete, a single measured value is determined and can be transmitted to the hub 60. In constructions that do not include a processor 65 in the node 55 or that do not analyze the data in the node 55, all the measured values are transmitted to the hub 60. As noted, it is preferable to provide a wired connection between the nodes 55 and the hub 60 such that the transmissions to the hub 60 are wired transmissions. However, wireless transmissions are also possible.

[0024] Figs. 4a, 4b, 4c, and 4d illustrate data from four different groups of sensors 45 as the data would be reported to the node. The following description of Figs. 4a, 4b, 4c, and 4d illustrate how the node 55 or hub 60 evaluates the quality of the data reported by the sensors 45 as well as how the final actual measurement is determined.

[0025] Fig. 4a illustrates a situation where all the sensors 45 return a reading 98 within the acceptable error margin 99 (shown as a rotated bell curve). That is, each sensor 45 has a reading accuracy with a particular standard deviation, illustrated as the error margin 99. All operating sensors 45 that report a value that is less than two standard deviations from a median are considered of good quality. These readings 98 are averaged, and the result is presented as the actual measurement to the control system. In addition to the actual measurement, the node 55 or the hub 60 can report an expected accuracy. The expected accuracy is dependent on the variance of the readings 98 and how many sensors 45 are averaged to achieve the result. The uncertainty can also be estimated by the range of the data provided by the sensors 45.

[0026] Fig. 4b illustrates a situation in which one of the sensor signals 101 is drifting between values. Using the method described with regard to Fig. 4a, the node 55 or the hub 60 can exclude the sensor 45 with the incorrect value and can compute both the average and the uncertainty of the actual measurement based on the remaining sensors 45. A sensor 45 that is excluded for a significant time due to its distance from the other readings, e.g., 30 seconds, will be permanently excluded and latched to faulty (marked or identified as faulty). The sensor 45 can only be included in the calculations after a user evaluates the reading 98, replaces the sensor 45, checks the cable etc. and reactivates the sensor 45. [0027] Fig. 4c illustrates a situation similar to that of Fig. 4b in that there is a faulty sensor 45. However, rather, than drifting, the faulty sensor 45 provides data 102 that simply drops off at some point in time and goes into saturation (maximum or minimum value). This saturation could occur periodically or randomly or could be a permanent drop-off. The node 55 or hub 60 monitors the sensor signals 98 over time to detect such abnormal behavior. For example, if the signal shape is significantly different than the other sensor signals as in Fig. 4b, is saturated as in Fig. 4c, or contains a lot of noise in comparison to the estimated accuracy from the calibration, the sensor 45 is latched to faulty (identified as faulty) and ignored. Again, this faulty condition needs to be present for a period of time (e.g., 30 seconds) to make this determination. It can be that an event such as a lightning strike is disturbing the signal 102 for a short time. This should not result in a permanent latch to faulty. That is, only consistent faults over a significant amount of time are permanently disregarded. Once the signal 102 is identified as faulty in the situation of Fig. 4c, the faulty signal 102 is handled as described with regard to Fig. 4b.

[0028] Fig. 4d illustrates a situation where the sensors 45 are not properly calibrated and therefore provide significantly different outputs 98. In this situation, only the median signal 103 is selected as all other signals are outside of the two-times standard deviation range or latched to faulty and no longer considered. This is clearly not a desirable operating condition as the selected median signal 103 could be incorrect as well. The high value of the reported uncertainty range notifies the user that the reading 103 is not reliable and that the sensors 45 should be recalibrated or replaced. While the sensor reading 103 reported is the median sensor result, the uncertainty range will be computed by using at least two sensor signals, thus resulting in a large uncertainty, particularly if only a few sensors are operational, and their outputs 98 are significantly different from one another.

[0029] As illustrated in Fig. 3, the hub 60 includes a plurality of wire connectors 80 arranged to receive wired connections from the individual nodes 55. The hub 60 is arranged to connect to ten different nodes 55 with other hubs 60 allowing for fewer or more connections. In addition, the hub 60 includes an ethernet connection 85 that allows for communication with an outside computer system such as a plant control system or the like. In preferred constructions, the ethemet connection 85 is a power over ethemet connection that allows for the provision of electrical power to the hub 60. The hub 60 also includes an antenna 90 that provide for the wireless transmission of data in cases where the ethernet connection 85 is not available.

[0030] Returning to Fig. 2, a schematic illustration of the hub 60 provides additional details.

The hub 60 includes a communications module 95 that receives the data from the nodes 55 and passes the data to a processor 100 and/or a data storage device 105 such as a solid-state drive.

In arrangements in which the nodes 55 do not process the data but rather pass the data to the hub 60, the hub 60 analyzes the sensor data using the processor 100 to eliminate any sensors 45 that may be providing incorrect or bad measurements. The hub 60 could then notify the operator regarding the failed or inaccurate sensors 45. The processor 100 within the hub 60 then analyzes the data from the remaining sensors 45 for each node 55 to determine the value for that measurement. As discussed with regard to the nodes 55, the processor 100 could simply average the sensor values that are thought to be good data or could use a more complicated scheme.

Once a value for each node 55 is determined, that data and any associated metadata (e.g., sensor location, date, time, etc.) is compressed.

[0031] Fig. 2 illustrates a separate compression module 110, however it should be understood that the processor 100 preferably includes the compression module 110 and performs the compression function. The data, including metadata such as the sensor location, the time of the measurement, and the like are compressed to allow for the quick and efficient transmission of the data to the outside system. The compression scheme is such that the data from all the nodes 55 can be analyzed and transmitted in real time allowing for the continuous monitoring of the data being measured without a delay that might cause issues controlling the turbine 10 or other devices.

[0032] The hub 60 includes a transmission module 115 that manages and completes the transmission of data from the hub 60 to the external system. When an ethernet connection 85 is available, the data can be transmitted via that ethernet connection 85. However, in many applications the ethernet connection 85 is not available. In these situations, the hub 60 wirelessly transmits the data to the external system. The compression of the data allows for the complete transmission of the data from the hub 60 using less than fifty milliwatts plus or minus twenty percent during the time period the transmission is occurring. [0033] In many applications, it is preferable to send the data redundantly using both wireless communication and the ethemet. Wireless communication can be more power efficient than ethemet communication due to the relatively large power consumption of some ethernets (particularly for fast network speeds). The quantity of data being transmitted is small which results in an optimized power consumption. By transmitting wirelessly, one can connect to the sensors directly with wireless technology. The wireless communication can be enabled over a mesh network which allows for redundant transmission paths ensuring operation without loss of real-time or service even if some repeaters are damaged. The redundant communication available using wireless communication increases the likelihood that the measurements remain available if the ethemet connection is cut and allow for a simple and fast integration of a new control system. That is, even if the control system is damaged one can use another system to link to the wireless data without needing to reroute cables. Additional functionality can be enabled in retrofitting of the facility without affecting the hardware setup.

[0034] As previously discussed, the hub 60 includes a power-over-ethernet connection 85 that allows for the delivery of power to the hub 60 via the ethernet connection 85. However, in many situations the ethernet connection 85 is not available. To address these situations, the hub 60 includes an energy storage system 120 including one or more rechargeable batteries 125 and an external renewable power supply 130 in the form of one or more photovoltaic cells (PVC) 135, often referred to as solar cells or solar panels that generate electricity in response to exposure to light.

[0035] Long-life batteries 125 having a lithium-based chemistry are designed to last through 18,000 charges and discharges, or about thirty years. In one construction, batteries 125 having a chemistry based on lithium iron phosphate (LiFeP04) are employed. The solar panels 135 have a surface area of less than 125 square inches (0.08 square meters) plus or minus twenty percent. This combination of battery 125 and solar panel 135 allows for the full operation of the hub 60 with only minimal exposure to suitable light (i.e., light in the wavelengths absorbed or converted by the PVC 135). In one construction, two hours of suitable light, with the aforementioned solar panels 135 provides enough power to operate the hub 60 for one week. The processor 100 or another battery controller includes algorithms that greatly extend battery life by controlling the charging levels, charging rates, discharge rates, etc. for the battery 125 to provide for the projected life of thirty years and up to 18,000 charges. In preferred constructions, the battery control algorithms allow for trickle charging of the batteries 125 to extend the operating time for the hub 60 under limited light circumstances.

[0036] In one construction, the hub 60 can receive measurements from nine nodes 55 including thirty-six sensors 45 with metadata, and transmit this data over two hundred meters once per second, while consuming only forty milliwatts of electrical power. The hub 60 is capable of simultaneous wired communication and power, via power over ethemet (PoE) 85, and is capable of switching between wired and wireless communication by detecting channel issues and reacting accordingly. The hub 60 can communicate with redundant sensor nodes 55 for temperature, pressure, humidity, vibration, or any other measurable property and any one hub 60 can communicate with multiple types of nodes 55 (i.e., measuring pressure, temperature, vibration, etc.) simultaneously.

[0037] The hub 60 provides real-time data from broadband sensors 45. The measured data is compressed at the hub 60 or node 55 to enable real-time transmission of high bandwidth sensors 45. For example, the hub 60 can be connected to a three-axis vibration sensor 45 sampling at 20 kHz. The data is measured and transferred to the hub 60 where it is split into frequency bands (e.g., 85 bands per axis, each 117Hz in width). The resulting data for each axis is then transmitted once per second from the hub 60.

[0038] The circuitry of the hub 60 (i.e., the processor 100 and battery management system) allows for trickle charging and trickle usage from the solar panel 135 and battery system 125. Thus, very small solar panels 135 can be used, and very power efficient electronics can be used, with the battery 125 adding temporal flexibility and buffering between power gathering and power usage. The battery management extends battery life to at least twenty years via programmed battery management algorithms.

[0039] Processing at the nodes 55 and hubs 60 reduces the very energy-intensive data sending and allows for only interesting or compressed data to be sent rather than all data (overall reduction in power consumption). The use of multiple nodes 55 connected to a single hub 60 with wired connections between the nodes 55 and the hubs 60 drastically reduces the power consumption per node 55 and transfers that power requirement to the hub 60 where it is better managed. The preferred ratio of nodes 55 to hubs 60 is in the range of seven to one and ten to one.

[0040] Often, the hub 60 is positioned in an environment that can be harmful to the operation of electronics. The hub 60 therefore includes a housing 140 that contains all the components of the hub 60 and protects the components from excessive moisture, temperature, vibration, electromagnetic fields and the like. While the antenna 90 is positioned outside of the housing 140 in the construction of Fig. 3, it could be partially or completely disposed within the housing 140 in some constructions.

[0041] In use, the sensors 45 are positioned in and around the turbine 10 or the turbine auxiliaries to measure the desired data. The sensors 45 are preferably redundant sensors 45 that each feed one of the nodes 55. However, other constructions may include multiple sensors 45 measuring different values and each feeding one node 55. In some constructions, each node 55 provides some data analysis to reduce the data load being transferred to the hub 60. Each node 55 is connected to the hub 60 via a wired connection with preferred hubs 60 being connected to up to ten nodes 55. The hub 60 receives the data and performs the necessary analysis or data parsing. The operations performed on the data could include an analysis for bad or incorrect data as previously discussed. However, other analysis or parsing could occur for different data types. The data, once analyzed, is compressed with its associated metadata by the hub 60 and then transmitted from the hub 60.

[0042] The battery management system of the hub 60 controls the charging and discharging of the battery 125 to extend the operating life of the battery 125 while providing the necessary power for transmission and processing of the data. In general, the hub 60 consumes in average less than 50 mW for continuous transmission at a data rate of 1 data package per second from all the connected nodes 55. Thus, if ten nodes 55 are connected to the hub 60, ten data packages per second would be transmitted.

[0043] Although an exemplary embodiment of the present disclosure has been described in detail, those skilled in the art will understand that various changes, substitutions, variations, and improvements disclosed herein may be made without departing from the spirit and scope of the disclosure in its broadest form. [0044] None of the description in the present application should be read as implying that any particular element, step, act, or function is an essential element, which must be included in the claim scope: the scope of patented subject matter is defined only by the allowed claims.

Moreover, none of these claims are intended to invoke a means plus function claim construction unless the exact words "means for" are followed by a participle.

Claims

CLAIMS What is claimed is:

1. A data acquisition system comprising:

a hub including a plurality of wired connections, each connection connected to one of a plurality of nodes that includes at least one sensor, each wired connection operable to deliver measured data from the sensors;

a processor operable to analyze the measured data of one of the plurality of nodes and to generate analyzed data indicative of the measured data collected by each of the sensors;

a data compressor coupled to and partially defining the hub, the data compressor operable to compress the analyzed data; and

a transmitter coupled to and partially defining the hub, the transmitter operable to transmit the compressed analyzed data.

2. The data acquisition system of claim 1, wherein each node includes between three and eight sensors, and wherein each sensor coupled to the node is operable to measure the same parameter.

3. The data acquisition system of claim 2, wherein the processor is operable to determine if one of the sensors is a faulty sensor based on the measurement provided by the sensors, and wherein the processor disregards measured data from the faulty sensor.

4. The data acquisition system of claim 1, wherein the hub transmits the analyzed data at a rate of at least one data packet per second per node and uses less than 50 mW on average during the transmission.

5. The data acquisition system of claim 1, wherein the hub includes an ethernet connection to an external network, and wherein power is provided to the hub via the ethemet connection.

6. The data acquisition system of claim 1, further comprising a battery positioned within the hub and operable to provide power to at least the data compressor, and the transmitter, and wherein the battery has a chemisty comprising lithium iron phosphate (LiFeP0₄).

7. The data acquisition system of claim 6, further comprising a solar panel positioned to charge the battery in response to an exposure to light, wherein the solar panel has a surface area of less than 125 square inches (0.08 square meters).

8. The data acquisition system of claim 1, wherein the processor is disposed in the hub and is operable to analyze the measured data of each of the plurality of nodes and to generate analyzed data indicative of the data collected by each of the hubs.

9. The data acquisition system of claim 1, wherein the processor is a first of a plurality of processors and wherein each of the plurality of processors is disposed in one of the plurality of nodes and is operable to analyze the measured data of the one of the plurality of nodes and to generate analyzed data indicative of the data collected by the associated node.

10. A data acquisition system comprising:

a plurality of nodes, each node including a plurality of sensors each positioned to measure a single parameter and output measured data indicative of the single parameter;

a hub including a plurality of connectors, each connector arranged to connect to one of the plurality of nodes to provide communication therebetween;

a processor positioned between one of the plurality of nodes and the hub and operable to receive the measured data from each of the plurality of sensors of at least one node, to analyze the measured data, and to generate analyzed data indicative of the single parameter measured by the plurality of sensors;

an ethernet connection coupled to and partially defining the hub, the ethernet connection arranged to interconnect the processor and an external network and to provide electrical power to the hub;

a transmitter coupled to and partially defining the hub, the transmitter arranged to transmit data to the external network; and

a selector coupled to and partially defining the hub, the selector operable to select one of the ethernet connection and the transmitter to transmit the analyzed data to the external network.

11. The data acquisition system of claim 10, wherein each node includes between three and eight sensors.

12. The data acquisition system of claim 11 , wherein the processor is operable to detect a faulty sensor based on the measurement provided by the sensor, and wherein the processor disregards data from the sensor if the sensor is determined to be faulty.

13. The data acquisition system of claim 10, wherein the hub transmits the analyzed data at a rate of at least one data packet per second per node and uses less than 50 mW on average during the transmission.

14. The data acquisition system of claim 10, further comprising a battery positioned within the hub and operable to provide power to at least the processor, and the transmitter, and wherein the battery has a chemisty comprising lithium iron phosphate (LiFeP0₄).

15. The data acquisition system of claim 14, further comprising a solar panel positioned to charge the battery in response to an exposure to light, wherein the solar panel has a surface area of less than 125 square inches (0.08 square meters).

16. The data acquisition system of claim 10, wherein the processor is disposed in the hub and is operable to analyze the measured data of each of the plurality of nodes and to generate analyzed data indicative of the measured data collected by each of the hubs.

17. The data acquisition system of claim 10, wherein the processor is a first of a plurality of processors and wherein each of the plurality of processors is disposed in one of the plurality of nodes and is operable to analyze the measured data of the one of the plurality of nodes and to generate analyzed data indicative of the data collected by the associated node.

18. A data acquisition system comprising:

a plurality of nodes, each node including a plurality of sensors each positioned to measure a single parameter and output measured data indicative of that single parameter;

a hub including a plurality of connectors, each connector arranged to connect to one of the plurality of nodes to provide communication therebetween;

a processor coupled to and partially defining the hub, the processor operable to receive the measured data from each node, to analyze the measured data, and to generate analyzed data indicative of the single parameter measured by the plurality of sensors for each node;

a transmitter coupled to and partially defining the hub, the transmitter coupled to the processor and operable to transmit the analyzed data for each node, wherein each transmission includes one data packet for each of the plurality of nodes, and wherein each data packet is transmitted at a rate of at least once per second and the hub consumes on average less than 50 mW during the transmission;

a battery coupled to and partially defining the hub, the battery operable to provide power to the processor and the transmitter; and

a solar panel operable to selectively charge the battery.

19. The data acquisition system of claim 18, wherein each node includes between three and eight sensors.

20. The data acquisition system of claim 18, wherein the processor is operable to detect a faulty sensor based on the measurement provided by the sensor, and wherein the processor disregards data from the sensor if the sensor is determined to be faulty.

21. The data acquisition system of claim 18, wherein the solar panel has a surface area of less than 125 square inches (0.08 square meters).

22. The data acquisition system of claim 18, wherein the hub includes an ethemet connection to an external network, and wherein power is provided to the hub via the ethemet connection.