Patent Application
20090265583
The present invention relates to data transfer devices and methods. More particularly, it relates to an apparatus and method for transferring data from a machine or process monitoring device over both a relatively low-bandwidth control data network and a relatively high-bandwidth bulk data network.
In industrial process control environments, such as factories or industrial plants, various types of machinery are distributed about the industrial environment to maximize the efficiency of a process being performed by the machinery. In most processes it is necessary to measure environmental and process conditions such as temperature, pressure, flow rates, vibration and the like in order to ensure proper process characteristics and to determine whether process machines require preventive maintenance or repair. Additionally, in a process control system, control signals indicative of a measured condition are communicated over a control data network to and from various process control devices which are also referred to herein as field devices. Examples of control data networks include HART, FOUNDATION™ fieldbus and PROFIBUS™ networks.
Typically, a field device may measure one or more conditions, such as temperature, pressure or vibration, and generate one or more scalar values or status messages based on the measured conditions. These scalar values and/or status messages are typically communicated via a control data network which is part of a process control system that controls various machines and processes in the industrial environment. In some systems, machine fault values are generated at the field device and these values are communicated to a central processor via the control network. The central processor may use such information in an advisory fashion to make sometimes urgent decisions regarding machine shut-downs and alarms. Also, the central processor may communicate with a maintenance department in order to schedule preventative maintenance or repair activities.
In such an environment, machine maintenance personnel often do not have access to raw data, also referred to herein as bulk data, that a field device uses in generating machine fault values or status values. This may be because the fault condition was transitory in nature and the related data was lost, or because the amount of data is too large for transmission across a low-bandwidth control data network which is typically bandwidth restricted and suitable only for transfer of data such as scalar values and status alert messages. As a result, maintenance personnel often cannot determine the underlying problem with a machine due to lack of meaningful data.
Thus, there is a need for a field device that is capable of communicating control data over a control data network while also communicating raw or bulk data over a bulk data network.
The above and other needs are met by a machine monitoring apparatus for collecting, processing and communicating machine data. In a preferred embodiment, the apparatus comprises one or more sensors that may be attached to or adjacent the machine for generating signals indicative of a performance parameter of the machine. An analog-to-digital converter converts the signals generated by the one or more sensors to bulk digital data corresponding to the sensed performance parameter. A processor receives and analyzes the bulk digital data and generates control digital data based on the bulk digital data, where the control digital data comprises one or more scalar values or status messages related to the operational performance of the machine as indicated by the bulk digital data. The apparatus includes a first interface for providing access to the control digital data via a control data network, and a second interface for providing access to the bulk digital data. The first interface is also referred to herein as a control data network interface and the second interface is also referred to herein as a bulk data network interface.
In some embodiments, the first interface is compatible for communication with a control data network selected from the group consisting of a FOUNDATION™ fieldbus network, a PROFIBUS™ network and a Hart network. In some embodiments, the second interface is compatible to communicate the bulk digital data via a data link selected from the group consisting of an RS-422 link, an RS-485 link, an RS-232 link, an IEEE-1394 link, a Universal Serial Bus link, an Ethernet link, a Bluetooth wireless link and a IEEE 802.11 wireless link. In some embodiments, the second interface is compatible to communicate the bulk digital data to a removable data storage device selected from the group consisting of a portable magnetic hard disk drive, a flash memory device, an optical memory device, a CD drive and a DVD drive. In some embodiments, the second interface is compatible to communicate the bulk digital data to a portable computing device selected from the group consisting of a portable vibration data collector, a portable vibration data analyzer, a personal digital assistant (PDA) and a notebook computer.
In another aspect, the invention provides a method for assisting in the diagnosis of a machine fault by communicating data corresponding to a machine condition. In one embodiment, the method includes steps of:
(a) collecting bulk data indicative of an operational condition of a machine;
(b) analyzing the bulk data using a first processing device disposed adjacent the machine to generate one or more control data values or messages indicative of the operational condition of the machine;
(c) communicating the one or more control data values or messages over a control data network having a control data network bandwidth;
(d) making the bulk data available for communication over a bulk data network having a bulk data network bandwidth that is significantly greater than the control data network bandwidth;
(e) accessing the bulk data via the bulk data network using a second processing device in communication with the bulk data network; and
(f) processing the bulk data using the second processing device to determine details regarding the operational condition of the machine, wherein such details are not communicated by the one or more control data values or messages communicated in step (c). In preferred embodiments, the second processing device comprises a computer system or handheld data analyzer used by machine maintenance personnel to diagnose machine performance.
Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.
Further advantages of the invention are apparent by reference to the detailed description in conjunction with the figures, wherein elements are not to scale so as to more clearly show the details, wherein like reference numbers indicate like elements throughout the several views, and wherein:
Referring to
In various embodiments, the communication pathway 18 may be a serial data link such as an RS-422, RS-485, RS-232 or IEEE-1394 link, a USB link, an Ethernet link, or a wireless connection such as a Bluetooth or Wi-Fi link. In some embodiments, the bulk data system 20 is a locally-connected a portable computing device, such as a laptop computer, a portable vibration data collector and/or analyzer, or a personal digital assistant (PDA). In yet other embodiments, the bulk data system 20 is a removable storage device, such as a portable hard disk drive, a USB drive, SD memory card, mini-SD memory card, micro-SD memory card, Pro Duo memory card, a CD-ROM drive, a DVD-ROM drive, a flash memory device, or the like.
Referring now to
Through the bulk data network, various embodiments of the invention provide maintenance personnel access to bulk data that is indicative of the condition of a machine. Without access to the bulk data, the maintenance personnel would have access only to the scalar data from the control network, which may indicate the general condition of a machine but does not necessarily represent why that condition exists. That is, significant bulk data is not typically available from a process control system due at least in part to bandwidth limitations of the control network. The field device 10 of FIGS. 1 and 2A-2B cures this problem by providing an interface to a dedicated, high-bandwidth communication pathway 18 for transfer of the bulk data for analysis by the maintenance personnel.
The foregoing description of preferred embodiments for this invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiments are chosen and described in an effort to provide the best illustrations of the principles of the invention and its practical application, and to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled.
