Electrical circuit training device and method

An electrical training simulator allows students to assemble electrical circuits, including motor control circuits, utilizing a variety of lab schematics. The electrical training simulator allows an instructor to induce faults into the student-assembled circuit, thereby requiring the student to apply troubleshooting skills utilizing the lab schematic and digital multimeter to analyze and locate the introduced fault in the circuit. Electrical components are fixedly attached to a component mounting plate. In one embodiment of the invention, the instructor introduces the faults through a fault control panel attached to the electrical training simulator, where the fault control panel is not within view of the student. In another embodiment, the faults may be introduced wirelessly through a remote controller.

BACKGROUND OF THE INVENTION

The present invention generally relates to training simulators for electrical circuits and more particularly to a training simulator and method of training which allows students to configure electrical circuits, such as those commonly found in industrial applications, according to specified laboratory schematics. The training simulator further allows the student to test the functioning of the circuits. The training simulator further allows an instructor to introduce faults into the circuits configured by the student, thereby requiring the student to troubleshoot the circuit using various testing protocols including using metering devices, while employing safety protocols required for working with electrical circuits.

Training simulators can provide a novice in a particular field with hands-on practical training for situations which may be encountered in the real-world environment of that field. Such devices are particularly helpful in vocational training in technical fields. The use of a simulator allows the student to be introduced to concepts and problem solving which might, if encountered in the real world, present risk of physical harm and/or property damage. The field of electrical technology, which involves, among other things, electrical circuits, reading of electrical schematics, PLC and motor controls, and OSHA standards, is a field in which training is greatly enhanced by using training simulators, thereby avoiding the risks associated with live switchgear. As a result, several different electrical training simulators have been developed and are known.

Electrical training simulators typically present a front panel with AC and DC power sources, resistors, capacitors, transformers, relays, and related devices and components encountered in the real-world environment. These trainers are generally designed to introduce students to the basic principles of electrical circuits, in both direct current and alternating current environments, industrial controls, 3-phase power supplies along with 3-phase resistive loads, capacitive loads and inductive loads, motor starters, motors, programmable logic controllers, and related concepts. The electrical training simulators may also a lock-out/tag-out switch which provides critical training for safe operations when working with electrical circuits.

The simulators will allow a student, utilizing a wiring diagram, to build an electrical circuit by connecting a power supply and various components with connecting leads, such as banana connectors. Once the circuit has been assembled, these simulators typically allow the student to test the circuit and to troubleshoot any problems in the circuit with various diagnostic tools, such as digital multimeters, amp clamps, megohmmeters, phase rotation meters and other diagnostic devices, to isolate and identify the problem. Some simulators provide means for an instructor to induce a fault in the student-assembled circuit, thereby providing the student the opportunity to troubleshoot the circuit to determine the fault. Such exercises are very valuable in teaching the student the appropriate process for troubleshooting problem in electrical circuits and the safety precautions to be taken in the process.

Vocational training for certain fields, such as power generation, power distribution, telecommunications, etc., should be particularly rigorous because of the inherent complexity of the equipment utilized in those fields, and because of the potential magnitude of loss of life and/or property presented by failures in those fields. Thus, it is desirable that an electrical training simulator provide a substantial number of options to an instructor to induce faults in each student-assembled circuit. It is also desirable that the faults be induced in such a manner that the student is not able to short-cut the troubleshooting exercise by visually inspecting components of the simulator to determine the nature of the fault. For example, some prior art simulators utilize switches on the bottom or backside of a component to induce the fault, thereby allowing a student to look underneath the component or at the backside of the simulator panel to identify the fault. It is desirable that an electrical training simulator be configured such that is does not provide any visual indication of the induced fault. It would also be desirable that an instructor is capable of inducing the faults remotely from the electrical training simulator.

It is also desirable to have an electrical training simulator configured to have multiple panels so that more than one student may be trained on a single simulator at the same time but reducing the expense of the simulator by allowing some shared components.

SUMMARY OF THE INVENTION

Embodiments of the present invention address the above-described desired features of an electrical training simulator. The electrical training simulator may be utilized to train and educate persons in the operation, maintenance and troubleshooting of electrical control systems utilized in a variety of industrial and municipal applications, including power generation, telecommunications, manufacturing, the like. Embodiments of the present invention allow students to apply what they have learned in the classroom through the trainer to identify, build/wire and troubleshoot a variety of electrical circuits, including motor control circuits utilizing a variety of lab schematics provided by the training personnel. Each lab starts with basic circuits using transformers/power supplies, indicating lights, various types of switches. Building upon the basic circuits the students assemble more complex circuits, including motor control circuits using contactors, control relays, timing relays and a 3-phase brake motor.

The electrical training simulator is configured to allow instructors to generate faults or alarms within the student-assembled circuits to train student technicians in proper troubleshooting techniques. The introduced faults can simulate a number of different circuit malfunctions, including a failed source or supply, bad indicating light, failed contractor switch or coil, or bad momentary switch. The student learns basic troubleshooting skills using the lab schematic and digital multimeter to analyze and locate the introduced fault in the circuit. The invention further provides training for students to follow the procedures required to establish an electrically safe work condition (ESWC), including safe execution of lockout and tagout (LOTO) procedures and hot-cold-hot procedures.

Existing trainers typically utilize removable modular components having accessible fault switches which the instructor may set as desired to induce faults in the circuit. Because the components of existing trainers are removable, students can gain physical access to visually ascertain which components have triggered fault switches. However, all components of the embodiments of the presently disclosed electrical training simulator are fixedly attached into the device, preventing any visual assessment of the components. Embodiments of the present electrical training simulator thus prevent students from gaining any advantage which otherwise might be gained from visually inspecting the sides and back of the components. This feature enables the instructional staff to consistently measure student performance based upon the diagnostic techniques they will be required to utilize in real world applications without any advantage gained from visual inspection of switch position. All electrical components may be pre-mounted to each side of embodiments of the present invention, eliminating the need for students to share modules, select specific modules from inventory, and install the modules prior to the start of an exercise. This feature saves time, allowing the student to spend more time working on the actual exercise. In addition, with prior art module-type trainers, there may be a limited number of modules, thereby limiting the number of like labs which can be performed at one time.

Embodiments of the presently disclosed electrical training simulator do not utilize modular components, but rather utilize built-in components which are not accessible or removable by students. In addition to the advantages discussed above, this configuration reduces the possibility of handling damage to the components which can occur with prior art systems which utilize modular components which are removable from the training simulator.

Embodiments of the presently disclosed training simulator may have four sides comprising two opposite-facing work panels connected at each end with a side plate thereby forming an enclosure having an interior. The work panels each provide exterior access to power supplies, lock-out/tag-out switching, transformers, relays, processor controls, switches, indicator lights, and terminal blocks for a single student, using connecting leads, to assemble, test, and trouble-shoot electrical circuits. The interior contains components and connecting boards and wiring required for the operation of the training simulator. The interior is accessible through one or both side plates, which may be pivotally attached to one of the work panels with hinges or other connecting hardware to allow the side plates to be pivoted open, for human entry into the interior. This configuration allows easy access to the interior by authorized personnel for configuration and maintenance of the various components of the simulator. However, it is to be appreciated that, given the size of the side panels, opening a side panel to access the interior of the simulator may be limited to authorized personnel by locks or like security devices. This feature of the simulator prevents unauthorized access during any supervised activities or simulation exercises. The two-panel configuration allows a single training simulator to be simultaneously utilized by two different students, each working on opposite sides of the simulator.

Embodiments of the present electrical training simulator allow an instructor to induce faults in student circuits either remotely or from a panel hidden from the view of the student. For example, the fault panels may be located the side plates. With this configuration, there will typically be a separate fault panel dedicated to each work panel, with fault panel set within an box mounted on each of the side plates Alternatively, the faults may be induced through a microprocessor-based control system employing a plurality of available communications systems including standard WiFi, private Wifi or direct hard wire serial links. These, combined with a PC based application program, allow the operator to induce faults may include issues such as a failed source or supply, bad indicating light, failed contactor switch or coil, and/or a bad momentary switch.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the Figures,FIGS. 1-4show an embodiment of the electrical training simulator100.FIG. 1shows a first work panel102of the simulator100andFIG. 2shows a second work panel104of the simulator100, where first work panel102and second work panel104may be disposed back-to-back and conjoined by side106and side108and may be configured into a four-sided unit having an accessible interior. Alternatively, an embodiment of the electrical simulator may comprise a single work panel and a non-functioning panel in back-to-back relation and conjoined by sides and configured into a four-side unit having an accessible interior. Embodiments of the simulator100may also be configured as transportable units having wheels or rollers. Alternatively, an embodiment of the electrical simulator may comprise a single work panel and a non-functioning panel in back-to-back configuration. All embodiments of the four-sided unit have an interior portion which allows access to the backsides of first work panel102and second work panel104. One or both of side106and side108may be pivotally attached to first work panel102or second work panel104by hinges or the like, allowing first work panel102or second work panel104to be pivoted open to allow human access as required for gaining access to the backsides of work panels102,104and other components located inside the electrical training simulator100for setting up or maintaining the simulator. Alternatively, sides106,108may be fastened to first work panel102and second work panel104with fasteners or like means.

In one embodiment of the invention, first work panel102and second work panel104may be simultaneously utilized by two different students to assemble different circuits as per schematics provided by training staff. Both first work panel102and second work panel104may have a single power switch.

First work panel102and second work panel104each comprise component mounting plates110and terminal plates112. The electrical components of first work panel102and second work panel104may be identical and for purposes of this disclosure, the components disposed within component mounting plates110of first work panel102and the components disposed within component mounting plates110of second work panel104are identical. The components are fixedly attached to the component mounting plates110,112. For purposes of this disclosure, the term “fixedly attached” is defined to mean that removal of the components from the component mounting plates110,112, requires the use of a tool. This feature of the invention prevents a student from gaining any visual advantage by manual removal of the components from the component mounting plates110,112.

Among the components fixedly attached to the component mounting plates are a fused 208 VAC/120 VAC transformer114, AC drive116, and a 24 VDC power supply118. Terminal plates112comprise a plurality of terminals for power supplies, switches, lights, overload relays, control relays, timing relays, interposing relays, resistors, diodes, motor connections, overload protection and connectors for a lock-out/tag-out switch. First work panel102and second work panel104also comprise lock-out/tag-out switch120and hot-cold-hot measuring terminals122. First work panel102and second work panel104further comprise squirrel cage motor124.

The embodiment of electrical training simulator100shown inFIGS. 1-4also have a first fault box enclosure130for first work panel102and a second fault box enclosure132for second work panel104. First fault box enclosure130and second fault box enclosure132are identical on the inside, each containing a plurality of fault switches140as shown inFIG. 3(for clarity, lead lines are only shown for a few of the eighty switches shown inFIG. 3).FIG. 4shows that handle134faces toward the first work panel102, providing a visual indicator of the work panel associated with the fault switches contained within the first fault box enclosure130. Similarly, the second fault box enclosure132has a similar handle which faces toward the second work panel104. The faults introduced by switches140can simulate a number of different circuit malfunctions, including a failed source or supply, bad indicating light, failed contractor switch or coil, or bad momentary switch. The student learns basic troubleshooting skills using the lab schematic and digital multimeter to analyze and locate the introduced fault in the lab schematic. The fault box enclosure130and its fault switches140are configured such that a student assembling a circuit on either the first work panel102or the second work panel104are unable to see the position of any of the fault switches, thereby preventing the student from having any visible indication of the fault.

FIGS. 5-7depict a second embodiment of the present electrical training simulator200which comprises components which enable remote fault introduction.FIG. 5shows a first work panel202of the simulator200andFIG. 6shows a second work panel204of the simulator200. First work panel202and second work panel204are disposed back-to-back and conjoined by side206and side208thereby forming an enclosed mobile unit having interior210as shown inFIG. 17. One or both of side206and side208may be pivotally attached to first work panel202or second work panel204by hinges226or the like, allowing first work panel202or second work panel204to be pivoted open to allow human access as required for setting up or maintaining the electrical training simulator200. Alternatively, sides206,208may be fastened to first work panel202and second work panel204with fasteners. First work panel202and second work panel204may be simultaneously utilized by two different students to assemble different circuits as per schematics provided by training staff.

First work panel202and second work panel204each comprise component mounting plates210and terminal plates212. The electrical components of first work panel202and second work panel204may be identical and for purposes of this disclosure, the components disposed within component mounting plates210of first work panel202and the components disposed within component mounting plates210of second work panel204are identical. Among those components are a fused 208 VAC/120 VAC transformer214, AC drive216, and a 24 VDC power supply218. Terminal plates212comprise a plurality of terminals for power supplies, switches, lights, overload relays, control relays, timing relays, interposing relays, resistors, diodes, motor connections, overload protection and connectors228for a lock-out/tag-out switch. First work panel202and second work panel204also comprise lock-out/tag-out switch220and hot-cold-hot measuring terminals222. First work panel202and second work panel204further comprise squirrel cage motor224.

FIG. 6shows second work panel204having a plurality of connecting leads250extending between different component terminals, as would be done by a student following a prepared schematic to build a specific circuit as provided in a prepared schematic.

FIG. 7shows side206or208of an embodiment of the electrical training simulator200.FIG. 7indicates a side “A” which refers to first work panel202and a side “B” which refers to second work panel204. Spare connecting leads250′ may be hung on hooks or the like on either side206or208as shown inFIG. 7.FIG. 7also shows cantilevering desktops230A,230B.

FIG. 8Aschematically depicts a power supply232which may be utilized for providing 208 VAC three phase power to work panels102,104for embodiments of the invention which utilizes a local fault induction.FIG. 8Bschematically depicts a power supply232′ which may be utilized for providing 208 VAC three phase power to work panels202,204for embodiments of the invention which utilize a remotely located digitally operated fault control system240.

FIG. 9schematically depicts a power supply234output to lock-out/tag-out switches on work panels102,104,202,204.

FIG. 10is a block diagram depicting an embodiment of a remotely located digitally operated fault control system240utilized in embodiments of the electrical training simulator200. An embodiment of fault control system240may control up to 256 individual relays that are connected to the electrical training simulator200for introducing faults into a student-assembled circuit. Fault control system240comprises two sections, being a local control system (“LCS”)250and a plurality of relay output boards (“RYOs” or “RYO boards”)270, typically ten, but as configured may be as many as 16. As noted previously, the ability of this system to handle up to 256 RYO boards is possible when larger addressing switches are employed. The LCS250communicates to each of the RYO boards270via a duplex fiber-optic daisy chain system with each of the RYOs having an individual address which may be set up through a 4-bit DIP switch on the RYO board. As previously noted, this DIP switch may be as large as an 8-bit allowing up to 256 RYO boards270in this same communication system for a total of 1024 relays. Other configurations would allow even more.

FIG. 11provides a table showing how each of the RYO boards270may be provided a unique address in both binary and decimal format by 4 position dip switches. When the LCS250commands an output, it comes with an address, so a specific RYO board270turns on or off according to the address. Each command issued from the LCS250is passed from RYO270to RYO270before returning to the LCS250, but only those RYOs270having the same address as the LCS command will respond. WhileFIG. 11depicts a four-bit switch, larger switches may be used, such as an 8-bit, which would provide for up to 256 boards on a single communication loop.

FIG. 12is a block diagram showing the complete fault control system consisting of a single Local Control System or LCS250and remote Relay Output Boards (RYO) for fault control. The LCS250consists of a small mother board with mounting headers for installation of a credit-card sized, low-power, 1 GHZ, Linux open hardware ARM processor board252, such as a BEAGLEBONE Black Wireless available through BEAGLEBOARD.org. This board contains a built-in WiFi communication system including antennas and is powered by the mother board. The ARM processor board252is attached to the LCS motherboard via its two 46 pin header strips. The motherboard also contains the fiber-optic transmitter and receiver for communication to the RYOs270. The motherboard252also has a RS-232 port provided via a DB9 connector. The LCS250is designed to receive commands from WiFI connected devices, such as laptops, tablets, etc., through a controller application program. In addition, the WiFi used may be a private WiFi system or by employing the RS-232 port this may be a direct connection to any laptop or desktop with the proper LCS application program installed. The LCS250thereafter communicates with the applicable RYO boards270with the controller application program allowing the operator to run each RYO270individually or, if required, in groups. Embodiments of the invention may utilize fiber-optic cables to communicate signals received through the wireless connection to fault relay boards built into the electrical training simulator200.

The mother board of the LCS250is powered from a 12-volt supply provided by the training simulator200. Connections on the two 46 pin header strips on the mother board provide for a universal asynchronous receiver-transmitter (UART 1) for operation of the fiber optic transmitter and receiver for RYO communication and a second UART (UART 2) that is converted to RS-232 levels for connection to a laptop or other computer if necessary. This connection can also be utilized for system checking of the training simulator itself. Normal connections are through the local or private WiFi network. The LCS mother board has an address DIP switch which allows multiple fault control systems240to be controlled from a single laptop or desktop computer through the local WiFi network, thereby allowing fault introduction into multiple electrical training simulators200from a single device.

FIG. 13is a block diagram showing the design and operation of the RYO board270. WhileFIG. 13shows an embodiment having 16 relay outputs, other quantities may be used as required for other embodiments of the invention. Each of the RYOs utilized in the fault control system240may have 16 mechanical relays272that can be turned on or off by the operator of a laptop or desktop in communication with the RYO270through the LCS250. The output contacts for each relay272are typically rated at 8 amps and rated to switch up 240 VAC. Each relay272has one normally open and one normally closed contact with a common armature, allowing the RYO boards270to be wired in either configuration as required by the specific load. The RYO boards270employ relatively simple but high performance 8-bit processors. The processor communicates via the RYO board's fiber optic devices. The RYO board270is programmed to accept all communication from the LCS250and respond only to those commands that concur with the RYO board's specific communication address, as discussed above. Each RYO is powered by a remote 10 to 14 VDC (12 volt nominal) power supply at 0.5 amps max.

Each RYO board270has 16 outputs available on 16 individual terminal strips labeled TB1 through TB16, typically configured with eight on the left side of the board and eight on the right side of the board. A fiber optic transmitter and receiver will typically be on the lower left-hand side of the RYO270while a terminal strip (TB17) is for the volt power supply input. Light emitting diodes (“LEDs”) are provided for all 16 relay outputs. A separate LED, located on the lower left-hand side of the board, is provided to indicate that the RYO is transmitting. Two additional LEDs, located on the lower right-hand side of the board. The first, a processor “heart beat” indicator, flashes once per second to indicate that the processor on the RYO board is functioning properly. The second LED on the lower right-hand side of the board is illuminated when 12 volts is applied to TB17.

The LCS250and RYOs270both use 850 nm wavelength fiber optic technology capable of operating at 1 mega baud to deliver commands to specific relays with no noticeable delay. A UART (RB5 and RB2) is used for fiber optic communication to the LCS250. A second communication loop I2C is used along with a MICROCHIP I/O expander to drive two 8-bit driver circuits and 8 relays each, for a total of 16 outputs.

FIGS. 14-16show RYOs270mounted in the interior210of the electrical training simulator200. As shown inFIG. 14, five RYOs270are mounted on the inside walls of work panels202,204. The RYOs270are mounted on standoffs (not shown). The standoffs allow wires to be connected and disconnected from each of the terminal blocks of the RYOs without damage to the RYO board.FIG. 15shows a plurality of RYOs270set within the interior210of an embodiment of the electrical training simulator200.FIG. 17also shows an optional positioning of LCS250in the interior210of the electrical training simulator. Also shown is a 5 vdc power supply258for LCS250and a 12 vdc power supply278for the RYOs270. Fiber optic cables280provide the connections between the LCS250and the RYOs270.

Having thus described the preferred embodiment of the invention, what is claimed as new and desired to be protected by Letters Patent includes the following: