Generic Wide-Input Range Energy Harvesting Power Supply PART NO PhotoVoltaic Energy Harvester (PVEH) is a:

Transcription

1 Generic Wide-Input Range Energy Harvesting Power Supply PART NO PhotoVoltaic Energy Harvester (PVEH) is a: Generic Wide-Input Range Energy Harvesting Power Supply "PVEH_12-5a": 12volt Solar Panel (rated) Input to 5volts at 1/2-ampere Output with embedded safety circuits and easy-to-use hookups. Features include: > Goof-proof input wiring interface (impossible to hook-up incorrectly) > Wide-range DC source input (that can also accept some ac sources) designed specifically for a wide assortment of solar panels, and other energy harvesting resources > Built-in over-current (resettable fuse) protection > Built-in, high-power transient over-voltage protection > DC Link (input) filter (large enough to properly filter AC sources) > Fixed output voltage converter with integrated current limiting (0.5Amps maximum) to protect against damaging the PVEH when the output is (accidentally) shorted > Output voltage filter > User-chosen application-specific output wiring Interface The PVEH_12-5a Product is a unique solution to a growing problem of recharging many types of battery-based devices when "off-the-grid" and away from traditional energy sources (like motor vehicles, other batteries, generators, etc.) Some examples of applications may include: power-losses for extended periods due to large storm damage; when on-location or working in regions (there are many) where the power-grid does not exist (think Doctors-Without-Borders); or when out camping and getting-away for a while; to name a few. Many existing Solar Battery Charging products fail to perform as described (per "feedback" and blogs), are limited in their applicability, or are too expensive for the value that they provide to the end user. The ubiquitous USB-charging cable for many of these devices, lack a generic, well-designed, affordable interface to widely available power, until the PVEH_12-5a. The PVEH_12-5a does not require the user to only use a specific solar panel, or output cable, as both can be configured by the user to fit specific needs and resources. Unlike most other Solar Panel-based battery chargers, the PVEH_12-5a is designed to use safely a wide assortment of off-the-shelf energy harvesting (12volts-rated) solar panels that are environmentally exposed to sources of dangerous voltages (like nearby lightning), due to special high-power transient protection circuits. The PVEH_12-5a operates properly even when the solar panel is supplying a voltage near its high-end open-circuit voltage of 22volts, or way down around 9volts when shaded by trees or operating in cloudy conditions. It is configured so that the user may make use of any input and output cabling needed per application (no soldering required) via screw-clamp terminal block connections. A "one of its kind" input circuit even provides completely "goof-proof" do-it-yourself wiring capability. The PVEH_12-5a uses industrial-grade premium-quality through-hole-technology (for maximum shock and vibration protection, and long service life) energy-harvesting components on a small (3.240" x 1.876") printed circuit board that can be embedded into other products or into its own stand-alone enclosure (designed for the SERPAC-111). This (almost Heathkit-style) design is a thru-hole only product that can be built by any skill level assembler (if you can solder, you can build it). It is extremely inexpensive (see BOM and Step 2's parts list), and can be easily modified to any specific application needs. Custom printed circuit boards (including silkscreen changes) can also be created for high-volume users, upon request. The last three

2 steps of the "instructions" include the Top and Bottom Copper printed circuit board views, with the detailed schematic, respectively. As shown in the series of detailed instructions, though, the use of a printed circuit board is not necessary, given that the prototype is actually point-to-point wired (for those so inclined). The "instructions" include 30 steps, covering an introduction, the parts list, circuit board assembly overview, tools and general assembly notes, step-by-step assembly, tests and results, operations and hook-ups with application and solar panel information, troubleshooting voltage measurements, specifications, top and bottom printed circuit board views, and a fully annotated detailed schematic. A complete GERBER (CAM) file set is available for those wishing to fabricate their own printed circuit boards (useful for those wishing to build many PVEH units instead of just one kit). The PVEH was designed using EAGLE PRO tools, and the design (*.sch and *.brd) files are also available (free) for those that wish to use them as a starting point for their own custom variations (using EAGLE's free downloadable toolset), like changing components, or using their own silkscreen, or different board shape for a different enclosure, etc. Time Required: 1 hour or less, depending depending on experience Experience Level: Beginner Required tools and parts: Soldering Iron, solder, wire (side or flush) cutters, needle-nose pliers, a small flat-blade screwdriver for attaching input and output wires to the terminal blocks. If using the designed-for-enclosure, and installing cables through this plastic box, means for drilling appropriately sized holes (for your input and output cables) will also be needed. Bill of Materials: Qty Jameco SKU Component Name C1 = 2200uF, 50volts (input filter) Aluminum Axial Capacitor This is a polarized component that MUST be installed correctly to ensure proper and safe operations 1 C2 = 390uF, 50volts (output filter) Aluminum Radial Capacitor This is a polarized component that MUST be installed correctly to ensure proper and safe operations D1 = 2amps, 600volts, single-phase full bridge (input goof-proof) recitifier This is a polarized component that MUST be installed correctly to ensure proper and safe operations 2 D2 & D3 = 23.1/25.7volts reverse-standoff/breakdown Bidirectional, 1500watts TVS (input over-voltage protection) Diode These bidirectional diodes may be installed in either direction (NOT polarity sensitive) D4 & D5 = 100volt, 1amp, 580mV@1Amp forward voltage drop, fast recovery, Axial Schottky Diode This is a polarized component that MUST be installed correctly to ensure proper and safe operations F1 = 1.1/2.2Amp hold/trip 60Vac/dc 150mOhm, Radial PTC Resettable (input over-current protection) Fuse This bidirectional Fuse may be installed in either direction (NOT polarity sensitive) IC1 = 5Volts output at 0.5Amps, up to 40volts input, Step-down, 52kHz SMPS Regulator in PDIP-8 package This is a polarized (pin-function specific) component that MUST be installed correctly to ensure proper and safe operations 1 L1 = 390uH 1.6Amp 0.288ohm Axial Power (unshielded) Wirewnd Inductor This bidirectional Inductor may be installed in either direction (NOT polarity sensitive) TB1 = BLUE (for the input connections) 2 Position, 250volts, 16amps, 14-26AWG Screw-rising cage clamp, horizontal mate, wire-to-board terminal block This terminal block (BLUE for input) should be installed so that the input wiring cage-clamps face away from the board TB2 = GREEN (for the output connections) 2 Position, 300volts, 20amps, 12-24AWG Screw-rising cage clamp, horizontal mate, wire-to-board terminal block This terminal block (GREEN for output) should be installed so that the input wiring cage-clamps face away from the board BOX (optional enclosure, specific box for Printed Circuit Board Layout); 3.6"x2.25"x1.5" ABS Plastic The Serpac #310 prepunched/perforated (0.1" grid) insulating prototype board for the #111 box may be used for hand-wiring this kit Step 1 - Introduction to the PVEH (this step) TEST CONNECTIONS examples This step (#1) provides a simple overview of the PVEH, introducing the assembler to the general architecture and some of its functions prior to building the kit.

3 (reference the PVEH Functional Block Diagram): + The source of power, a 12volts-rated solar panel for instance, is attached to a (blue) terminal block that includes a "goof-proof-wiring" circuit, called D1 (it is NOT possible to wire up the power source incorrectly). + The input power passes through a positive-temperature-coefficient (bi-state resistor, called R1, with low resistance when cool and very high resistance when hot) resettable "fuse" that serves as an over-current-protection device for both the PVEH and the power source. + On the circuit side of the "fuse" there is, in parallel, a pair of over-voltage-protection "TransZorbs" to limit the input voltage to a safe level called D2 and D3, a DC Link (input) filter capacitor called C1, and the voltage conversion regulator called IC1. > The "active" circuitry (IC1) of the PVEH is a National Semiconductor (now from Texas Instruments) #LM2574 "Simple Switcher" that "steps-down" an input voltage (as high as 40volts) to our desired +5.0volts output with a 0.5Amps output current capacity. > Associated with this switching regulator is a 330uH "energy-transferring" inductor called L1; and, > A pair of (in parallel) "Catch Diodes" called D4 and D5. By using a pair of these diodes (instead of the usual one diode) the overall efficiency of the circuitry is improved, with a 13% drop in heat losses due to the nonlinear shift in their operating point. + The PVEH's output voltage is filtered by C2 prior to being made available at the (green) terminal block for the application's use. There are many possible sources of power for the PVEH, and these will be discussed later in the "OPERATION" steps. Step 2 - Parts List (from BOM) (this step) TEST CONNECTIONS examples This step (#2) briefly familiarizes the assembler with the components used to perform the functions identified in step #1. (reference the Parts List, from the BOM): + C1 (input filter capacitor), and + C2 (output filter capacitor), and + D1 (input "goof-proof" diode-steering circuit), and + D4 and D5 (switching regulator's "catch diodes"), and + IC1 (switching regulator integrated circuit), and + TB1 (blue "input" terminal block), and + TB2 (green "output" terminal block) ALL are POLARITY sensitive that MUST be installed only in one orientation to ensure proper and safe operations from the PVEH. Detailed assembly steps (#5, #6, #8, and #9) provide additional information for each of these components proper installation procedures.

4 > D2 and D3 (over-voltage-protection diodes), and > F1 (over-current-protection "fuse"), and > L1 (330uH inductor) are not polarity sensitive, and these 2-lead components may be installed in either direction. Step 3 - Location of all components to be installed onto the circuit board (this step) TEST CONNECTIONS examples This step (#3) briefly shows the general location of the components in the PVEH assembly introduced in steps #1 and #2. (reference the BOARD with COMPONENTS diagram): The Circuit Board (actually a board layout assembly diagram in this view) is shown surrounded by photographs of the actual components used during assembly, including the "part" (reference) designators used in the schematics and the parts list (step #2). In this particular view, all of the orientation-sensitive (polarized) parts that MUST be installed carefully, are shown with RED arrows identifying the installation locations: + IC1, D4, and D5 will be installed in Step #5 + D1 and TB1 will be installed in Step #6 + C2 and TB2 will be installed in Step #8, and + C1 will be installed in Step #9. There are four components that are NOT polarity-sensitive, that may be installed in either (of their 2-leaded) direction, and are shown with BLUE arrows identifying their installation locations: > L1 will be installed in Step #5 > D2, D3, and R1 will be installed in Step #7.

5 Step 4 - Tools and General Assembly Notes (this step) TEST CONNECTIONS examples This step (#4) identifies the tools needed for the circuit board assembly work, with general assembly notes: The tools needed for the PVEH assembly are simple and minimal: > A needle-nose pliers is used to bend the leads on various components > A (flush or side) wire cutter is used to trim the leads next to the board > An appropriately-sized soldering iron (with solder) is needed for this simple assembly. Since there are no tiny or surface mount components, most sizes work >>>>> GENERAL ASSEMBLY NOTES

6 Step 5 - Detail Steps for installing IC1, D4, D5, and L1 This step (#5) provides detailed steps on installing IC1, D4, D5, and L1 (in that order). A set of brackets... [ ]... is provided at each sub-step for a check-mark in order to keep track of completed steps as the assembly process progresses. (reference the Step 5 detailed assembly drawing for these sub-steps): + IC1 installation: 1) [ ] Locate IC1 (LM2574) and orient the leads so that pin 1 (package "dot") is in the upper right corner, as shown in the detail view's upper left quadrant. 2) [ ] Insert all eight leads through their respective holes. While holding the top of the package, securing the IC to the top of the printed circuit board, bend the leads on the bottom of the board so that they hold the IC in place on the board. 3) [ ] DO NOT APPLY TOO MUCH HEAT from the Soldering Iron; we want to melt the solder, not weld it. Carefully solder (ensuring a good molten flow), from the bottom of the board, all eight leads of IC1, making sure that there are no solder bridges between any of the leads. + D4 and D5 installation: 1) [ ] Locate D4 and D5. These two diodes are smaller in size that D2 and D3, as shown in the detailed assembly drawing's bottom left quadrant. D4 and D5 each have a white band on one end of their bodies, indicating where their cathode end is. These diodes MUST be installed in the proper direction for the PVEH to work properly. 2) [ ] Using the needle nose pliers to hold the lead of each end of D4 (and then D5) bend the lead at a right angle (as shown in the detailed assembly drawing's upper right quadrant), on both ends, spacing the bends so that the leads will line up with the printed circuit board holes for both of these diodes. 3) [ ] Ensuring that the white (cathode) band end of D4 is downward, matching the band for its symbol on the silkscreen of the printed circuit board (as shown in details in the assembly drawing), insert the leads of D4 into the holes for it, pushing the diode's body clear down flat to the printed circuit board. It is important to have D4's body touching the printed circuit board because the top and bottom copper on the board are used to help remove heat that builds up in the diode while running under full load. While holding the body of D4 against the printed circuit board, bend its leads on the back of the board to hold it securely in place. 4) [ ] From the bottom of the board, solder both leads of D4, ensuring a good flow occurs (cold solder joints will disable this circuitry's proper functioning). 5) [ ] Using your (flush or side) wire cutters on the bottom of the board, hold each lead (to prevent it from flying off while cutting) as you cut the excess lead off at the solder connection. 6) [ ] Repeat all of these same assembly steps for D5. + L1 installation: 1) [ ] Locate L1. This inductor may be installed in either orientation (not polarity-sensitive). 2) [ ] Use the needle nose pliers to bend the leads (as you did for D4 and D5 in the above steps) so that the spacing of the leads match the two holes for mounting this inductor between IC1 and D4, as shown in the bottom portion of the detailed assembly view. 3) [ ] Insert the leads of L1 into the holes for it, pushing the inductor's body clear down flat to the printed circuit board (again for good heat removal purposes). Holding the inductor in place from the top, bend the leads on the bottom of the board securing it in place. 4) [ ] From the bottom of the board, solder both leads of L1, ensuring a good flow occurs. 5) [ ] Also on the bottom side of the board, using the wire cutters, hold and cut each of both leads of L1 close to the solder connections. >>> this completes step #5

7 Step 6 - Detail Steps for installing D1 and TB1 (this step) TEST CONNECTIONS examples This step (#6) provides detailed steps on installing D1 and TB1 (in that order). A set of brackets... [ ]... is provided at each sub-step for a check-mark in order to keep track of completed steps as the assembly process progresses. (reference the Step 6 detailed assembly drawing for these sub-steps): + D1 installation: 1) [ ] Locate D1 (Black body, 0.5"x0.6"x0.2" with four leads) and orient the leads so that pin "+" (sloped top edge) is on the left, as shown in the detail assembly diagram's view. This component MUST be installed correctly to ensure safe and proper operation of the PVEH. 2) [ ] Insert all four leads through their respective holes. While holding the top of the package, securing D1 to the top of the printed circuit board, bend the leads on the bottom of the board so that they hold D1 in place on the board. 3) [ ] DO NOT APPLY TOO MUCH HEAT from the Soldering Iron; we want to melt the solder, not weld it. Carefully solder (ensuring a good molten flow), from the bottom of the board, all four leads of D1, making sure that there are no solder bridges between any of the leads. 4) [ ] Using your (flush or side) wire cutters on the bottom of the board, hold each lead (to prevent it from flying off while cutting) as you cut the excess leads off at the solder connections. + TB1 installation: 1) [ ] Locate TB1 (BLUE 2-position terminal block). This terminal block MUST be installed in the proper direction to ensure easy access to this input wiring interface during usage. The top portion of the step 6 detailed assembly drawing shows this detail. 2) [ ] From the bottom of the board, solder both leads of TB1, ensuring a good flow occurs (cold solder joints will disable this component's proper functioning). DO NOT CUT the excess pins of TB1. >>> this completes step #6

8 Step 7 - Detail Steps for installing D2, D3, and R1 (this step) TEST CONNECTIONS examples This step (#7) provides detailed steps on installing D2, D3, and R1 (in that order). A set of brackets... [ ]... is provided at each sub-step for a check-mark in order to keep track of completed steps as the assembly process progresses. (reference the Step 7 detailed assembly drawing for these sub-steps): + D2 and D3 installation: 1) [ ] Locate D2 and D3. These two diodes are larger in size than D4 and D5 (which were both installed during step #5), as was shown in the detailed assembly drawing's bottom left quadrant for step #5. D2 and D3 do NOT have a band on one end of their bodies, becasue they are bidirectional (two back-to-back series diodes) components. These diodes may be installed in either direction. 2) [ ] Using the needle nose pliers to hold the lead of each end of D2 (and then D3) bend the lead at a right angle (as was shown in the detailed assembly drawing's upper right quadrant of step #5), on both ends, spacing the bends so that the leads will line up with the printed circuit board holes for both of these diodes. 3) [ ] Insert the leads of D2 into the holes for it, pushing the diode's body clear down flat to the printed circuit board. It is important to have D2's body touching the printed circuit board because the top and bottom copper on the board are used to help remove heat that could build up in the diode when it is conducting during over-voltage-protection events. 4) [ ] While holding the body of D2 against the printed circuit board, bend its leads on the back of the board to hold it securely in place. 5) [ ] From the bottom of the board, solder both leads of D2, ensuring a good flow occurs (cold solder joints will impair this component's proper functioning). 6) [ ] Using your (flush or side) wire cutters on the bottom of the board, hold each lead (to prevent it from flying off while cutting) as you cut the excess lead off at the solder connection. 7) [ ] Repeat all of these same assembly steps for D3. + R1 installation: 1) [ ] Locate R1 (looks like an orange disc capacitor; but iy really is a two-state temperature-dependent resistor that behaves like a resettable fuse). R1 may be installed in either direction. Insert both leads of R1 into the holes for it (just behind D1) and push it down until the curves in the leads rest on top of the board. 2) [ ] While holding the top of R1, bend its leads on the back of the board to hold it securely in place. 3) [ ] From the bottom of the board, solder both leads of R1, ensuring a good flow occurs (cold solder joints will disable this component's proper functioning). 4) [ ] Using your (flush or side) wire cutters on the bottom of the board, hold each lead (to prevent it from flying off while cutting) as you cut the excess lead off at the solder connection. >>> this completes step #7

9 Step 8 - Detail Steps for installing C2 and TB2 (this step) TEST CONNECTIONS examples This step (#8) provides detailed steps on installing C2 and TB2 (in that order). A set of brackets... [ ]... is provided at each sub-step for a check-mark in order to keep track of completed steps as the assembly process progresses. (reference the Step 8 detailed assembly drawing for these sub-steps): + C2 installation: 1) [ ] Locate C2 (Black cylindrical body, 0.6"high x 0.63"dia. with two leads) and orient the leads so that pin "-" (gold stripe top to bottom on the case) is on the bottom edge, towards diodes D4 and D5, as shown in the detail assembly diagram's view. This component MUST be installed correctly to ensure safe and proper operation of the PVEH. 2) [ ] Insert both leads through their respective holes. 3) [ ] While holding the top of the package, securing C2 to the top of the printed circuit board, bend the leads on the bottom of the board so that they hold C2 in place on the board. 4) [ ] DO NOT APPLY TOO MUCH HEAT from the Soldering Iron; we want to melt the solder, not weld it. Carefully solder (ensuring a good molten flow), from the bottom of the board, both leads of C2, making sure that there are no solder bridges between any of the leads. 5) [ ] Using your (flush or side) wire cutters on the bottom of the board, hold each lead (to prevent it from flying off while cutting) as you cut the excess leads off at the solder connections. + TB2 installation: 1) [ ] Locate TB2 (GREEN 2-position terminal block). This terminal block MUST be installed in the proper direction to ensure easy access to this output wiring interface during usage. Various portions of the step 8 detailed assembly drawing shows this detail. 2) [ ] From the bottom of the board, solder both leads of TB2, ensuring a good flow occurs (cold solder joints will disable this component's proper functioning). DO NOT CUT the excess pins of TB2. ***** IMPORTANT USAGE NOTE ***** Unlike the "goof-proof" input wiring, where the DC power source may be connected to the PVEH in any polarity, the output connection MUST be connected properly to ensure that the polarity is correct for your application load. The bottom view of the step 8 detailed assembly drawing shows the correct +5volts connection (shown with a red wire) and the Ground return wire (shown with a black wire) for the application load. >>> this completes step #8

10 Step 9 - Detail Steps for installing C1, the last component (this step) TEST CONNECTIONS examples This step (#9) provides detailed steps on installing C1. A set of brackets... [ ]... is provided at each sub-step for a check-mark in order to keep track of completed steps as the assembly process progresses. (reference the Step 9 detailed assembly drawing for these sub-steps): + C1 installation: 1) [ ] Locate C1 (Black cylindrical body, 1.6"long x 0.71"dia. with two leads, one off each end) 2) [ ] Use the needle nose pliers to grasp the leads of the capacitor, one at a time, next to the body, bending the lead at a right angle, such that the leads line up with the printed circuit board holes. 3) [ ] Orient the leads so that pin "-" (silver stripe end to end on the case) is is to the right, and C1's black (top) rubber seal is to the left ("+" terminal), as shown in the detail assembly diagram's view. This component MUST be installed correctly to ensure safe and proper operation of the PVEH. 4) [ ] Insert both leads through their respective holes. 5) [ ] While holding the top of the package, securing C1 to the top of the printed circuit board, bend the leads on the bottom of the board so that they hold C1 in place on the board. 6) [ ] DO NOT APPLY TOO MUCH HEAT from the Soldering Iron; we want to melt the solder, not weld it. Carefully solder (ensuring a good molten flow), from the bottom of the board, both leads of C1. 5) [ ] Using your (flush or side) wire cutters on the bottom of the board, hold each lead (to prevent it from flying off while cutting) as you cut the excess leads off at the solder connections. >>> this completes step #9

11 Step 10 - Test Connections for Prototype PVEH_12-5a TEST CONNECTIONS < Steps 10 -> 19 > (this step) This step (#10) provides a description of the Test Connections and setup. A battery of eight tests were conducted on the PVEH_12-5a, two each at four different resistive load levels, to analyze the performance of the PVEH_12-5a (for developing the specifications - later). All eight of these tests used a Commercial-grade Data Acquisition System (DAS) for capturing copious quantities of data (an example of one small sampling is shown in step #11) for providing the summary information that follows in steps #12 to #19. (reference the "PVEH DAS Testing Setup" picture for the following information) A bench power supply, through a 1.00 Ohm power resistor supplies power to the PVEH_12-5a (left side of Setup picture). The voltage drop across this 1.00 Ohm resistor provides the input current measurement (1volt per 1Ampere). The power supply's postive lead is connected to the current measuring resistor. Remember, in actual usage-applications, this positive input can be connected to either terminal input on the blue terminal block. The "load" (right side of Setup picture) during these tests consists of (in series): 1) a 0.1ohms resistor for measuring the output current (0.1volts per 1ampere); 2) a fixed value (black body) 3ohms power resistor; 3) a 0ohms-to-10ohms (green body, slider) variable power resistor; and, 4) another fixed value (black body) 3ohms power resistor (to ground). There is a load connection/disconnection (on/off) switch installed in this series-connection of resistors to test surge recovery during these tests. The DAS used four channels during testing: 1) Input Voltage; 2) Input Current (voltage drop across 1Ohm resistor); 3) Output Voltage; and, 4) Output Current (voltage drop across 0.1ohms resistor). The nominal output voltage, during regulation (with sufficient input power) is +5volts at a maximum of 0.5Amps (typical rating for a USB power source). USB voltage sources generally have a +/-5% tolerance, which permits them to source in the range of volts to +5.25volts. Tests on five of my computers all have the voltage outputs on the various USB cables less than +5.00volts, with many of them just barely above the minimum voltage of +4.75volts. As will be seen in steps #13, #15, #17, and #19 that follow, the PVEH_12-5a supplies a voltage very close to +5.0volts output, even under heavy (least resistance) testing. >>> this completes step #10

12 Step 11 - Example DAS Analysis Plot and Tests Summary TEST CONNECTIONS & RESULTS < Steps 10 -> 19 > (this step) This step (#11) provides an example of the DAS Analysis screenshot. (reference "Example DAS Analysis Screen v test 9.jpg" for the following text) During DAS Test Sequence #9, twenty-four different input voltage levels were captured and analyzed for the highest, 17.1ohms, load resistance (minimum power level tested). This particular 6.117seconds sampling, is the fourteenth in that series of twenty-four, with 1,470 samples total for each of the four channels. The "statistics" pop-up window (upper left) provides the "mean" value, which is the average input voltage used for this particular test value. As will be seen (again) in steps #18 and #19, this input voltage of volts resulted in an input power of Watts, supplying volts to the 17.1ohms load for a total output power of watts, at a 57.81% power effiency. The "statistics" window also presents many other, sometimes, important data, including the standard deviation for the sampling span. For each of the four different resistance values as the load, two tests were conducted with their results combined for the power efficiency and output voltage plots, with the load being switched off and back on during portions of at least one of them analyzing power surge performance characteristics. The short table that follows summarizes these tests, and the presentation of these results in the following steps (#12 thru #19): Test #: Load Ohms: Number of Samples: Step # depiction: : shows power efficiency from >27.536volts input : shows output voltage from >27.536volts input : shows power efficiency from >27.543volts input : shows output voltage from >27.543volts input : shows power efficiency from >27.652volts input : shows output voltage from >27.652volts input : shows power efficiency from >27.566volts input : shows output voltage from >27.566volts input >>> this completes step #11

13 Step 12 - Power Efficiency for 10.2ohms Load TEST CONNECTIONS & RESULTS < Steps 10 -> 19 > (this step) This step (#12) provides a Plot of the Power Efficiency for a 10.2ohms load. (reference "10-2Ohms Efficiency.jpg" for the following text) As will be seen in step 13, the four lowest voltage input levels sampled during tests #2 and #3 failed to provide an output voltage above +4.75volts (deliberately tested for specification development reasons). The same four too-low input voltage samples also generate the first four lowest efficiency values plotted (see figure). These too-low (and can be disregarded) values are: Input Volts= Power Efficiency = Output Volts = % % % % The first "good" (greater than 4.75volts) output voltage (4.9544volts) was acquired during Test #2 when the input voltage was already at a (high) level of volts. For this efficiency plot point of 55.38%, the output power was at watts, as determined by an average of 1,648samples. As it turns out, the PVEH_12-5a is most efficient when it is supplying the most amount of power to the load. Therefore, the maximum efficiency of the tests conducted was achieved for this lowest resistance value of 10.2ohms tested, with the remaining three higher resistance values resulting in lower power efficiencies for the similar input voltage values tested (see steps #14, #16, and #18). A few other points of interest include: * The power efficiency reaches 60% somewhere between the input voltage samples of volts and volts. * The power efficiency reaches 62% somewhere between the input voltage samples of volts and volts. * The maximum power efficiency measured of 64.74% happened when the input voltage was volts, which is just above the typical open circuit voltage for a 12-volts rated solar panel. If this PVEH_12-5 were the only load (2.4591watts) on a well-lit 150Watt solar panel, then a voltage level near this value could be present as the input voltage. * For tests #2 and #3 combined, 57,637 samples spanning 39 unique input voltage values were evaluated for each of the four measured parameters for developing this efficiency plot. >>> this completes step #12

14 Step 13 - Voltage Outputs for 10.2ohms load TEST CONNECTIONS & RESULTS < Steps 10 -> 19 > (this step) This step (#13) provides a Plot of the Output Voltages for a 10.2ohms load. (reference "10-2Ohms OutputVolts.jpg" for the following text) As was seen in step 12, the four lowest voltage input levels sampled during tests #2 and #3 failed to provide an output voltage above +4.75volts (deliberately tested for specification development reasons). These too-low (and can be disregarded) values are: Input Volts= Output Volts = Once above 4.75volts on the output,the following first few tabulations show the steady rise, per input voltage, towards the ideal voltage of +5.0volts, which is achieved at the higher input voltage range: Input Volts= Output Volts = #samples (per voltage evaluated) , , , , , , , , , ,833 Again, for tests #2 and #3 combined, 57,637 samples spanning 39 unique input voltage values were evaluated for each of the four measured parameters for developing this output voltage plot. >>> this completes step #13

15 Step 14 - Power Efficiency for 11.6ohms Load TEST CONNECTIONS & RESULTS < Steps 10 -> 19 > (this step) This step (#14) provides a Plot of the Power Efficiency for a 11.6ohms load. (reference "11-6Ohms Efficiency.jpg" for the following text) As will be seen in step 15, the two lowest voltage input levels sampled during tests #4 and #5 failed to provide an output voltage above +4.75volts (deliberately tested for specification development reasons). The same two too-low input voltage samples also generate the first two lowest efficiency values plotted (see figure). These too-low (and can be disregarded) values are: Input Volts= Power Efficiency = Output Volts = % % The first "good" (greater than 4.75volts) output voltage (4.8392volts) was acquired during Test #4 when the input voltage was at a (barely high enough) level of volts. For this efficiency plot point of 51.85%, the output power was at watts, as determined by an average of 1,899samples. As noted during step 12, the overall efficiency drops over the whole span of input voltages as the power output drops (due to the increase in load resistance). In step 12, it was found that the highest efficiency sampled of 64.74% occurred with the input voltage = volts. In this step (14), with a higher load resistance and lower power output, the maximum efficiency point sampled is just 63.26% when the input voltage is at volts. A few other points of interest include: * The power efficiency reaches 60% somewhere between the input voltage samples of volts and volts. * The power efficiency reaches 62% somewhere between the input voltage samples of volts and volts. * For tests #4 and #4 combined, 76,917 samples spanning 35 unique input voltage values were evaluated for each of the four measured parameters for developing this efficiency plot. >>> this completes step #14

16 Step 15 - Voltage Outputs for 11.6ohms Load TEST CONNECTIONS & RESULTS < Steps 10 -> 19 > (this step) This step (#15) provides a Plot of the Output Voltages for a 11.6ohms load. (reference "11-6Ohms OutputVolts.jpg" for the following text) As was seen in step 14, the two lowest voltage input levels sampled during tests #4 and #5 failed to provide an output voltage above +4.75volts (deliberately tested for specification development reasons). These too-low (and can be disregarded) values are: Input Volts= Output Volts = Once above 4.75volts on the output,the following first few tabulations show the steady rise, per input voltage, towards the ideal voltage of +5.0volts, which is nearly achieved at the higher input voltage range: Input Volts= Output Volts = #samples (per voltage evaluated) , , , , , ,752 (# of samples is correct) , , ,896 Again, for tests #4 and #5 combined, 76,917 samples spanning 35 unique input voltage values were evaluated for each of the four measured parameters for developing this output voltage plot. >>> this completes step #15

17 Step 16 - Power Efficiency for 13.9ohms Load TEST CONNECTIONS & RESULTS < Steps 10 -> 19 > (this step) This step (#16) provides a Plot of the Power Efficiency for a 13.9ohms load. (reference "13-9Ohms Efficiency.jpg" for the following text) The first output voltage (4.9471volts) was acquired during Test #6 when the input voltage was at a level of volts. For this efficiency plot point of 52.42%, the output power was at watts, as determined by an average of 2,996samples. As noted during steps 12 and 14, the overall efficiency drops over the whole span of input voltages as the power output drops (due to the increase in load resistance). In step 12, it was found that the highest efficiency sampled of 64.74% occurred with the input voltage = volts. In step 14, with its higher load resistance and lower power output, the maximum efficiency point sampled was just 63.26% when the input voltage was at volts. In this step (16), with its even higher load resistance and lower power output, the maximum efficiency point sampled is just 61.32% when the input voltage is at volts. One other point of interest is: * For tests #6 and #7 combined, 79,718 samples spanning 34 unique input voltage values were evaluated for each of the four measured parameters for developing this efficiency plot. >>> this completes step #16

18 Step 17 - Voltage Outputs for 13.9ohms Load TEST CONNECTIONS & RESULTS < Steps 10 -> 19 > (this step) This step (#17) provides a Plot of the Output Voltages for a 13.9ohms load. (reference "13-9Ohms OutputVolts.jpg" for the following text) All of the 34 different input voltage levels sampled for tests #6 and #7 for this specific 13.9ohms load yielded above 4.75volts on the output. The following first few tabulations show the steady rise, per input voltage, towards the ideal voltage of +5.0volts, which is nearly achieved at the higher input voltage range: Input Volts= Output Volts = #samples (per voltage evaluated) , , , , , , , ,103 Again, for tests #6 and #7 combined, 79,718 samples spanning 34 unique input voltage values were evaluated for each of the four measured parameters for developing this output voltage plot. >>> this completes step #17

19 Step 18 - Power Efficiency for 17.1ohms Load TEST CONNECTIONS & RESULTS < Steps 10 -> 19 > (this step) This step (#18) provides a Plot of the Power Efficiency for a 17.1ohms load. (reference "17-1Ohms Efficiency.jpg" for the following text) The first output voltage (4.9478volts) was acquired during Test #9 when the input voltage was at a level of volts. For this efficiency plot point of 50.91%, the output power was at watts, as determined by an average of 1,162samples. As noted during steps 12, 14 and 16, the overall efficiency drops over the whole span of input voltages as the power output drops (due to the increase in load resistance). The following tabulates this trend, with the peak efficiency for this step at the end. Step Input Load Test #: Efficiency: Voltage= Resistance= #'s % ohms 2 & % ohms 4 & % ohms 6 & % ohms 8 & 9 > this completes step #18

20 Step 19 - Voltage Outputs for 17.1ohms Load TEST CONNECTIONS & RESULTS < Steps 10 -> 19 > (this step) This step (#19) provides a Plot of the Output Voltages for a 17.1ohms load. (reference "17-1Ohms OutputVolts.jpg" for the following text) All of the 37 different input voltage levels sampled for tests #8 and #9 for this specific 17.1ohms load yielded above 4.75volts on the output. The following first few tabulations show the steady rise, per input voltage, towards the ideal voltage of +5.0volts, which is nearly achieved at the higher input voltage range: Input Volts= Output Volts = #samples (per voltage evaluated) ,162 (from test 9) (less?) 2,232 (from test 8) ,736 (from test 9) , , , , , ,724 Again, for tests #6 and #7 combined, 79,718 samples spanning 34 unique input voltage values were evaluated for each of the four measured parameters for developing this output voltage plot. >>> this completes step #19

21 Step 20 - Testing for Higher Efficiency TEST CONNECTIONS (this step) This step (#20) provides a description of a Test that depicts how higher efficiency can be achieved with the PVEH. The first (original) version of the PVEH used a different 330uH power inductor that was both shielded and more efficient. Since the ideal inductor is not sourced nor is it available through JameCo, the kit design, as presented, so far, uses an inductor that is available through JameCo. The problem with the kitted inductor is that it is NOT shielded and is less efficient than the original unit. If more efficiency is needed, or if EMI may be an issue (when using the plastic box), then the original inductor (see part number in this step's attachment) may be better suited. NOTE, the original inductor's footprint does NOT fit the printed circuit board supplied with the JameCo version of this kit. (the Gerber Files for a different printed circuit board that does work with this original inductor's layout are available from GUSTECH) The previous steps showed the maximum achievable efficiency occurs at 64.74% for a 10.2ohms load when the input voltage is at volts. (see step 12's attachment) Using the original inductor, the maximum efficiency occurs at 69.63% for a 9.05ohms load when the input voltage is at volts. Additional testing (not presented here) also showed that at least an additional 1/2watt of power could be delivered from the PVEH, with much lower output switching noise, and at a higher (+5.02volts) voltage level than with the the kit version. An entirely different switching regulator would be needed (and are available from other distributors but not from JameCo) in order to achieve very high efficiencies (some are now available that can reach 95% efficiency). >>> this completes step #20

22 Step 21 - Operation - Hookup (DC sources) TEST CONNECTIONS OPERATION - HOOKUP (this step) This step (#21) provides a description of how to hookup the input and output wiring to and from the PVEH. CAUTION >> CAUTION >> CAUTION: When finished with this step, perform the "BEFORE POWER CHECK" of Step #25 (in the Troubleshooting section) prior to actually applying power to the PVEH. Do not install the board in its box until after the input and output wiring connection are made. [INPUT]: The PVEH has a full diode bridge circuit on the input "front-end" that behaves as a "goof-proof" wiring interface. The reason for this circuit configuration is because many solar panels, and some other DC power sources, do not include wiring that clearly identifies which lead is positive and which lead is the ground return line. The "goof-proof" input wiring circuitry simultaneously protects the PVEH from improper input power connections while also making it easy for anybody to use the PVEH with a wide assortment of potential power sources. The input power source "SHOULD BE" a DC source in the range specified (see specifications step). Since the input circuitry includes an AC-DC diode network, the user may be curious if it is possible to actually use the PVEH being powered from an AC source. This topic will be discussed in step 22. The top portion of the diagram for step #21 shows the input wiring connections to the blue terminal block, with the wiring passing through a hole installed in the box for this purpose. I connected the wires to the terminal block and looped a small length of the input wires under the board before installing the board in its box (as a strain relief method). [OUTPUT]: NOTE: Unlike the input interface, the output wiring is Polarized and MUST be performed properly to protect the appliance that is being powered by the PVEH circuitry. The bottom portion of the diagram for step #21 shows the output wiring connections for a standard USB cable (for charging cell phones, and other various battery-powered electronics). The cable does NOT have to be a USB cable; BUT, it DOES have to be connected properly. When using a USB cable, The positive (+) 5 volts is the red wire, and the ground return line (to the PVEH) is the black wire. The shield is not connected, and the two data lines that are green and white, are also not connected (cut short). Strip the red wire and black wire, pass the cable through a hole that you drill in the box for this output cable, and attach the output wires (as shown: red to +5 and black to Ground) to the green output terminal block (as shown in the diagram). I connected the wires to the output terminal block and looped a small length of the output wires under the board before installing the board in its box (as a strain relief method). After the connections are made to the input power source (with or without an inline power switch, your choice) and the output cable, the PVEH is almost ready to supply power to your electronics' load. CAUTION >> CAUTION >> CAUTION: Perform the "BEFORE POWER CHECK" of Step #25 (in the Troubleshooting section) prior to actually applying power to the PVEH. >>> this completes step #21

23 Step 22 - Operation - Hookup (AC sources) TEST CONNECTIONS OPERATION - HOOKUP (this step) This step (#22) provides a description of how to hookup the input and output wiring to and from the PVEH. CAUTION >> CAUTION >> CAUTION: When finished with this step, perform the "BEFORE POWER CHECK" of Step #25 (in the Troubleshooting section) prior to actually applying power to the PVEH. This particular step addresses the use of a low voltage alternating current source instead of a direct current one. See step 21 for wiring instructions, as this step only addresses performance data. The astute kit builder/hobbiest may have wondered why an ac source could not be used as an input to the PVEH since the front-end circuitry includes an AC-to-DC Full-wave bridge rectifier circuit. Well, actually, the PVEH can use an AC source, and this step shows how well it works. The top half of the diagram associated with this step shows the PVEH being driven by a Class 2 12Vac at 1Ampere "wall wart" power supply. The load for the tests were either "open circuit" (10.0ohms resistor disconnected) for "no load", or the "full load" of 10.0ohms connected. Note, even when the output load is disconnected, though, there is a load from the operating Integrated Circuit still pulling power through the input circuits from the ac source. NO (output) LOAD TEST DATA: AC input voltage = Vac at 60.00Hz DC Input voltage (measured at the positive lead of the input capacitor C1) = Volts DC. DC Output voltage = 5.082Volts DC. FULL (10.0ohms) LOAD TEST DATA: AC input voltage = Vac at 60.00Hz DC Input voltage (measured at the positive lead of the input capacitor C1) = Volts DC. DC Output voltage = 5.005Volts DC. For those kit builders that wish to use a different low level alternating current source than 12Vac, choose a transformer that ensures that the filtered DC input (on the positive lead of C1) is between the safe operating voltages for both the proper operation of the integrated circuit and the input over-voltage protection circuit activation voltages of: Vdc input minimum is about: 6.5Vdc Vdc input maximum is about: 24.0Vdc Most 12volt (DC) rated Solar Panels have a maximum open-circuit voltage of 22.0volts or less, and the over-voltage protection circuits were designed to protect the PVEH against high-voltage transients exceeding this value. For the advanced systems integrator and experimentors playing with the PVEH, I want to take this opportunity to let you know that the PVEH will also work when powered from most DC or AC output wind turbines. A note of caution is in order though. It is very important that the speed of the wind turbine not be so high that the open-circuit voltage rises to the point where the PVEH's over-voltage protection circuits start activating (a little above 24Vdc). Therefore, the wind turbine needs to be rated at 12volts only (most will operate in 24volt systems also - don't use them). Also, if connecting to a stock-ac output wind turbine, generally these are three phase permanent magnet altenators. The PVEH will work just fine by hooking up any two of the three AC wires. The power input will be a little off balance, but the input filter capacitor will smooth out the waveform just fine. CAUTION >> CAUTION >> CAUTION: Perform the "BEFORE POWER CHECK" of Step #25 (in the Troubleshooting section) prior to actually applying power to the PVEH. >>> this completes step #22

24 Step 23 - Operation - Hookup (solar panel to many PVEH's) TEST CONNECTIONS OPERATION - HOOKUP (this step) This step (#23) provides a description of how to hookup a single solar panel to several PVEH units charging several (one each) devices. CAUTION >> CAUTION >> CAUTION: Before actually executing this step or any other variation of it, perform the "BEFORE POWER CHECK" of Step #25 (in the Troubleshooting section) prior to actually applying power to the PVEH. This particular step is an application example of how to hookup several (five, for example) PVEH units to a single solar panel, with each PVEH charging a separate cell phone (could be games, or other USB-like chargable devices). As depicted in step #21, the output connections for each of the five PVEH devices need to be properly polarized for each load, typically as depicted and described in step #21. The inputs to each of the PVEH can be attached in either polarity, all in parallel, to the two wires coming from the solar panel. Note: the 20watts 12volts-rated solar panel depicted is the absolute minimum wattage-rating possible for this particular example, assuming direct overhead sunlight conditions for maximum charging capabilities. For most other applications, a larger wattage-rating solar panel will be required for proper power delivery to the five devices. For charging five devices in partial shade (in the woods at a campsite) at mid-day, a panel of 75watts or larger may be needed to fully charge all five loads simultaneously. Some more information on solar panel sizing is in the next, step #24. >>> this completes step #23

25 Step 24 - Operation - Hookup (solar panel list for PVEH's) TEST CONNECTIONS OPERATION - HOOKUP (this step) This step (#24) provides a list of some possible solar panels that will work with the PVEH (based upon specifications; not actual testing). This survey was conducted in July 2013, and is subject to (radical) change as product availability fluctuates wildly in this particular area. It is by no means an exhaustive listing, either. CAUTION >> CAUTION >> CAUTION: Before actually hooking up any solar panels to the input connector of the PVEH, perform the "BEFORE POWER CHECK" of Step #25 (in the Troubleshooting section) prior to actually applying power to the PVEH.

26 From Solarland USA: Model: Watts: Amps: Volts: Item: Price: SLP030-12U $ SLP050-12U $ SLP100-12U $ From Kyocera: Model: Watts: Amps: Volts: Item: Price: KD140SX-UFBS $ From SolarWorld: Model: Watts: Amps: Volts: Item: Price: SW130polyR6A $ From PowerUp: Model: Watts: Amps: Volts: Item: Price: BSP10 12V $58.00 BSP20 12V $99.00 BSP30 12v $ BSP40 12v $175/00 Harbor Freight Tools lists a Chicagor Electric Power Systems, 15 Watts, 12 Volt Solar Panel, Item #96418, for $ EarthTech Products sells a Voltaic DIY Solar Cell Phone Charger Kit with USB Port providing a 3.4watt solar panel and USB Battery Pack. Dozens of other sources, the vast majority surveyed, listed panels WITHOUT pricing ("call") which can mean that the solar panels are not available, or the pricing is fluctuating too much to list, or that they are ashamed of posting their high prices. BUYER BEWARE. Unless one pushes into the technical specifications for each of these solar panels, the true performance can only be estimated, at best. Remember that the advertised wattage rating is the absolute maximum possible under direct overhead full sunlight conditions (irradiance = 1kWatt per meter-squared), with significantly less power when the sunlight is at an angle (not directly overhead) or even a few clouds are in the sky. Realisitcally, a 100-watt panel's output, reduced by production tolerance, thermal affects, dust, and wiring and other losses could be as low as 68-watts in the middle of a clear day. So, the example 20watts solar panel shown in the previous example (Step #23) is truly idealistic; where a 50watts solar panel would be better for charging five different appliances in the middle of a clear day. CAUTION >> CAUTION >> CAUTION: one last time, perform the "BEFORE POWER CHECK" of Step #25 (in the Troubleshooting section) prior to actually applying power to the PVEH. >>> this completes step #24

27 Step 25 - DO THIS BEFORE APPLYING POWER TEST CONNECTIONS OPERATION - HOOKUP TROUBLESHOOTING (this step) DO THIS STEP -- IT IS IMPORTANT This step (#25), "BEFORE POWER CHECK," is an important one for circuit safety reasons and should be performed regardless of the kind of wiring hookups used in any kind of application. It is included as part of the Troubleshooting section because it is the first thing that should be examined if the PVEH fails to provide the proper output voltage when the input power is first applied. If this step is not performed, and an oversized board mounting screw is used in one of the holes, it is possible to destroy any circuitry attached to the output of the PVEH. DO THIS STEP -- IT IS IMPORTANT The recommended enclosure for the PVEH is the SERPAC#111. JameCo's # is a black version; less expensive ones are available from many different distributors. The prototype used for this project is a beige one. The enclosure includes four board mounting screws. (see step #21 for details). If the kit builder uses any screws other than those supplied with the SERPAC box it becomes important that the screws used to secure the PVEH circuit board in the enclosure do NOT have a screw heads that are TOO LARGE. This also applies to the use of flat and/or lock washers (which really shouldn't be needed in most applications). If an application includes an environment where high shocks or vibration levels may be encountered, it is recommended that the board mounting screws be "locked" into place use "Locktite" (or similar materials) on the screw threads. The safe size for the screw head, even with a flat or lock washer, is determined by the copper circle (shown in green in this diagram) on the top of the circuit board in the four mounting screw locations (see the diagram for this step). The one screw hole that is the issue for this step is the one closest to the integrated circuit. On one side of the screw hole is top side copper that is the high voltage DC power input to the integrated circuit, and on the other side this same screw hole is the output (+5v) voltage to the application load. If a flat washer or different (than supplied) screw that has a diameter that is larger than the copper (shown in green in this diagram) donut for this mounting hole, it may short out the high voltage to the output device when power is applied (potentially destroying your cell phone, toy, or appliance connected to the output of the PVEH). It is far better to not use this mounting hole (the other three should work OK for most typical applications) than to use a screw with a head too large, or (far worse) a washer that has a diameter that is too large. If you have determined that the screw used in this one particular hole is NOT shorting out the two cited copper planes (the screw head diameter is less than that of the copper ring for this mounting hole), then it is safe to use the PVEH as a power source for you application (provided it is designed for +5volts at no more than 500mA loading), and the input source may be connected and/or switched on. >>> this completes step #25

28 Step 26 - Troubleshooting, Measurements, In Case of Difficulty TEST CONNECTIONS OPERATION - HOOKUP TROUBLESHOOTING (this step) This step (#26), "Troubleshooting Measurements," should be (partially, thru step 26-5) performed before a load is actually connected to the output of the PVEH to ensure that all of the voltages are correct, especially those being applied to the load. With a known voltage source, with and without a load, voltmeter spot checks are made to verify functionality of the PVEH. Additional equipment is needed to perform this test: 1) a 12VDC power supply capable of supplying at least 1Ampere of current; 2) a voltmeter capable of reading 20VDC, or preferably, a Multimeter with several DC voltage ranges; and, a 10ohms power resistor (preferably with an inline switch) as a test load. Perform the following steps referencing the Troubleshooting Test Points Diagram for this step. In general, after a voltage source is connected to the input terminal block, the output voltage will first be checked without a load attached, and if OK, with a load attached. If both of these measurements are OK, then the PVEH is working, and it can be used to power your application circuitry at this point. If not, then troubleshooting steps are included at the end of step 26-4, and there are additional voltage measurements included for further analysis. ***** Step 26-1 Perform Step #25's visual check, at least, if you have not done so already. ***** Step 26-2 If using a 10ohms 3watts (or higher) resistor as a test load with an inline wired-switch, connect it across the output connector (GREEN Terminal Block) at this time. If no switch is wired inline, do nothing with your test load at this time. ***** Step 26-3 With the power TURNED OFF, connect your power supply leads to the input connector (BLUE Terminal Block) at this time. Note, it does NOT matter which input screw connection is used for the +12volts input; use the other screw connection for the power return (ground) input. >>>>> IMPORTANT NOTE: the input power return line is NOT electrically the same as the output Ground line, being offset by one diode's forward voltage drop within D1 > If the voltage was too high, repeat step #25. >>>>> If the voltage is too low, too high, or not present at all, then:

29 ----> CAREFULLY inspect the polarity of ALL components that must be installed correctly (in just one proper position), including: C1, C2, D1, D4, D5, and IC > CAREFULLY inspect all solder connections ensuring that a good solid fillet exists at each solder point. ----> CAREFULLY inspect that there are no solder bridges between any adjacent leads or solder pads. ----> Reflow all solder connections that appear to be cold solder joints because great connections are needed for full power flow in this circuitry ***** Step 26-5 Output Voltage with FULL Load: Turn on the switch to electrically connect the 10ohms test load (if yours has a switch) or, wire the 10ohms test load to the output connector (GREEN terminal block). Turn ON the Power Supply. The output voltage should be nominally +5.0volts (between 4.75volts and 5.20volts). Turn Off the Power Supply. Perform the tasks identified in steps 26-4's "IN CASE OF DIFFICULTY" if the measured voltage was not correct. >>>>> If the output voltage was correct with a test load attached, the PVEH is working correctly and can be used to power your application load at this time >>>>> ***** OTHER MEASUREMENTS FOLLOW: ***** Step 26-6 Voltage Drop Across the input fuse: Note: F1 is a temperature dependent resistor whose resistance increases significantly as the temperature rises (especially if too much current is flowing), and the test that follows assumes that F1 is at room (around 23 degrees C) temperature. Make sure the test load is disconnected (unwired or its switch turned off). Connect your DC voltmeter's positive lead to test point #1 (see figure: orange wire on lead of F1), and set the meter's range to 200mVDC full-scale, if it has one. Connect your DC voltmeter's negative lead to test point #2 (see figure: blue wire on lead of F1). Turn ON the power supply and note the voltmeter reading. The meter's voltage reading should be less than +20millivolts Turn Off the Power Supply. Connect the 10ohms test load (wire or turn on its switch). Set the multi/voltmeter's range to 2VDC full-scale, if it has one. Turn ON the power supply and note the voltmeter reading. The voltage drop across the input fuse should be less than +500millivolts Turn Off the Power Supply. ***** Step 26-7 Input voltage applied to IC1 after D1 and F1: Note: The proper voltages cited in this step assume that the input voltage from the power supply is 12.0volts at the input (BLUE) terminal block. Make sure the test load is disconnected (unwired or its switch turned off). Connect your DC voltmeter's positive lead to test point #3 (see figure: red wire on lead of C1 or D3). Connect your DC voltmeter's negative lead to test point #4 (see figure: black wire on lead of C1, D3 or D5). Turn ON the power supply and note the voltmeter reading. The output voltage should be nominally volts (between 10.15volts and 11.15volts). Turn Off the Power Supply. Connect the 10ohms test load (wire or turn on its switch). Turn ON the power supply and note the voltmeter reading. The output voltage should be nominally volts (between 9.60volts and 10.80volts). Turn Off the Power Supply. ***** Step 26-8 Output voltage from IC1 driving L1: Make sure the test load is disconnected (unwired or its switch turned off). Connect your DC voltmeter's positive lead to test point #5 (see figure: green wire on lead of L1). Connect your DC voltmeter's negative lead to test point #4 (see figure: black wire on lead of D5, C1, or D3). Turn ON the power supply and note the voltmeter reading.

30 The output voltage should be nominally +5.00volts (between 4.75volts and 5.20volts). Turn Off the Power Supply. Connect the 10ohms test load (wire or turn on its switch). Turn ON the power supply and note the voltmeter reading. The output voltage should be nominally +5.06volts (between 4.80volts and 5.30volts). Turn Off the Power Supply. >>> this completes step #26 Step 27 - Specifications of Components used in the PVEH TEST CONNECTIONS OPERATION - HOOKUP (this step) This step (#27) provides a brief listing of the major component specifications the PVEH, in the general order of signal flow, as depicted in this step's block diagram. By-Component Major Specifications: "Goof-Proof Wiring Interface" TB1 (JameCo # ): Color = Blue Maximum Working Voltage = 250volts Maximum Working Current = 16Amps Wire Range = 26 to 14 AWG D1 (JameCo #253286): Maximum Repetitive Peak Reverse Voltage = 1000volts Maximum average forward output rectified current at 55degrees C = 2.0Amps Operating junction and storage temperature range = -55 to +165 degrees C Maximum instantaneous forward voltage drop per leg at 3.14amps = 1.1volts Minimum instantaneous forward voltage drop per leg = 0.6volts at 10mAmps Maximum DC reverse current at 25 degrees C = 5.0uAmps ***** "Over-Current Protection" F1 (JameCo #199912):

31 Hold 1.60A 3.20A -40C 1.43A 2.86A -20C 1.27A 2.54A 0C 1.10A 2.20A +23C (nominal rating) 0.91A 1.82A +40C 0.85A 1.70A +50C 0.75A 1.50A +60C 0.67A 1.34A +70C 0.57A 1.14A +85C Maximum Rated Voltage = 60volts Maximum withstand Fault Current = 40Amps Typical Power in tripped state at 23degrees C = 1.50watts Minimum device resistance (not tripped) at 23 degrees C = 0.150ohms Maximum device (recovery) resistance 1 hour after tripping at 23degress C = 0.380ohms Maximum Time to Trip at 11Amps = 8.2seconds ***** "Over-Voltage Protection" D2 & D3 (Arrow #1.5KE27CA-T) spec each: Reverse Standoff Voltage = 23.10volts Minimum Breakdown Voltage = 25.70volts Maximum Breakdown Voltage = 28.40volts Maximum Clamping Voltage = 37.5volts Maximum Peak Pulse Current = 40.0Amperes (each) Peak Power Dissipation for 1mS = 1,500Watts (each) Peak Forward Surge Current for 8.3mS half sine wave = 200Amperes (each) ***** "DC Link Filter" C1 (JameCo #199479): Nominal Capacitance = 2,200uF Maximum Working Voltage = 50volts Maximum Ripple Current at 120Hz at 85degrees C = 1.422Amps ***** "Fixed Output Voltage Converter" IC1 (JameCo #156566): Minimum Output Voltage (with Vin 7V to 40V and Load = 0.1 to 0.5Amps) = 4.80volts Maximum Output Voltage (with Vin 7V to 40V and Load = 0.1 to 0.5Amps) = 5.22volts Typical Efficiency (with Vin = 12V and Load = 0.5Amps) = 77% NOTE: This is just for the IC; see steps 12, 14, 16, 18, & 20 for Efficiency of whole PVEH. Temperature Range = -40 to +125 degress C D4 & D5 (JameCo #312101): Technology = Schottky Barrier Peak Repetitive Reverse Voltage = 100volts Average Rectified Forward Current = 1Ampere (each) Non-repetitive Peak Surge Current = 50Amperes (each) Maximum Instantaneous Forward Voltage at 1Amp (each) at 25 degrees C = 0.79volts Maximum Instantaneous Forward Voltage at 1Amp for the pair of diodes at 25 degrees C = 0.57volts L1 (Arrow #IHD3EB391L): Nominal (+/-15%) Inductance = 390uH Maximum DC Resistance = 0.288ohms Rated Maximum DC Current = 1.6Amperes ***** "Output Filter" C2 (Arrow #EEU-FC1H391S): Nominal Capacitance = 390uF Maximum Working Voltage = 50volts Maximum Ripple Current at 100kHz = 1.610Amps Endurance = 5000hours *****

32 "Application Output Wiring Interface" TB2 (JameCo #160785): Color = Green Maximum Working Voltage = 300volts Maximum Working Current = 20Amps Wire Range = 24 to 12 AWG ***** >>> this completes step #27 Step 28 - Circuit Board TOP Layer X-Ray View TEST CONNECTIONS examples (this step) Circuit Board X-Ray View (red = top; blue = bottom from the top) From the "Readme CAM files_28aug13" file for this Circuit Board Design: PVEH_12-5a.cmp = Top Copper Layer (depicted in step #28) PVEH_12-5a.sol = Bottom Copper Layer (depicted in step #29) PVEH_12-5a.stc = Top Soldermask PVEH_12-5a.sts = Bottom Soldermask PVEH_12-5a.plc = Top Silkscreen PVEH_12-5a.gpi = Gerber Photoplot Info PVEH_12-5a.dri = Drill Rack Info PVEH_12-5a.drd = Drill Data

33 Step 29 - Circuit Board BOTTOM Layer X-Ray View TEST CONNECTIONS examples (this step) Circuit Board X-Ray View (red = top; blue = bottom from the top) From the "Readme CAM files_28aug13" file for this Circuit Board Design: PVEH_12-5a.cmp = Top Copper Layer (depicted in step #28) PVEH_12-5a.sol = Bottom Copper Layer (depicted in step #29) PVEH_12-5a.stc = Top Soldermask PVEH_12-5a.sts = Bottom Soldermask PVEH_12-5a.plc = Top Silkscreen PVEH_12-5a.gpi = Gerber Photoplot Info PVEH_12-5a.dri = Drill Rack Info PVEH_12-5a.drd = Drill Data

34 Step 30 - PVEH Schematic TEST CONNECTIONS examples (this step) Single Page schematic with embedded notes

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