CirKits.com SCC3-e1 12V Solar Charge Controller Assembly Instructions Instructions Rev: February 3, 2016 See http://www.cirkits.com/scc3/FAQ-SCC3.html for general information. See http://www.cirkits.com/scc3/scc3help.html for troubleshooting tips. General Hints and Tips: -Parts go on the side of the board with white lettering (silkscreen). -Do not overheat the semiconductors when soldering, especially the LED. -Use a clip-on heat sink when soldering semiconductor leads. -Only use electronic grade 60/40 rosin core solder or equivalent. -Acid core solder destroys electronic parts, don't use it. -A proper solder connection is shiny, smooth, and concave shaped. -Look at the photograph of an assembled SCC3 circuit board on http://www.cirkits.com/scc3/ for reference. Tools and materials for Construction and Alignment: Electronic grade soldering iron 60/40 rosin core solder Needle nose pliers Diagonal wire cutters #1 Phillips head screwdriver Fine gauge flat screwdriver for circuit adjustment volt meter Rubbing Alcohol and a tooth brush (recommended) 0-20 VDC variable power supply Follow and check all of the [] boxes as you proceed. The first assembly steps involve connecting the high current parts of the circuit. Be sure to use enough solder for these components. Locate the capsule of heat sink grease and the toothpick. [] Bend the leads of Q2-IRF4905 and D1-20L15 so that the parts fit into the board and the mounting holes line up with circuit board holes. [] Using the supplied toothpick, apply a thin coat of heat sink grease to the metal on the back side of the two TO-220 package parts,Q2-IRF4905 and D1-20L15. Grease the back of the heat sinks around the screw holes. [] Install D1, the 2 pin 20L15T TO220-package diode on top of one of the black metal heat sinks, place the diode and heat sink on the circuit board. Put one of the 4-40 screws through the back of the board. Place the 4-40 lock washer and nut on the end of the screw and tighten the screw. Bend the leads of D1 over the silvered areas on the bottom of the board, this gives a higher current connection. Solder to the board. [] Install Q2, the IRF4905 MOSFET transistor on top of the second heat sink and board using the other 4-40 screw, lock washer, and nut. Tighten the screw. Bend the Q2 leads over the silvered areas of the board, as was done for D1, then solder the leads. [] Wipe any excess heat sink grease from the parts and board with a tissue, wash your hands, keep the heat sink grease out of your eyes. [] Insert the fuse into the two fuse clips. Press the clips into the board at F1. Solder the fuse clips to the board, be sure not to use too much solder or you may solder the fuse to the clips. When working with long leaded parts, insert the leads into the board holes, bend the leads so that the part fits snugly to the board, solder the leads, then clip off the excess wire on the bottom of the board. [] Solder the 470uF capacitor to the board at C1. Align the +/- polarity on the capacitor with the + in the circle. The white stripe on the capacitor (- side) is closest to the 4 pin connector, CN1. [] Solder eleven 100nF capacitors (marked 104 or 0.1uF) to the board at C2,C3,C4,C5,C6,C7,C8,C9,C10,C11, and C12. [] Solder TM1, the thermistor, to the board. TM1 is a small black sphere. The thermistor may optionally be mounted near the battery, the TM1 leads can be extended with twisted pair wires. [] Solder TZ1, 27V Transzorb, it is a black disk marked V7270 or V270. Solder the resistors to the board. If you are unsure about the resistor color codes, verify the part values with an ohm-meter. [] Solder one 5.1 ohm (green brown gold) resistor at R22. [] Solder one 330 ohm (orange orange brown) resistor at R17. [] Solder one 1K ohm (brown black red) resistor at R23. [] Solder six 10K (brown black orange) resistors: R10,R11,R14,R15, R18,R25. [] Solder one 22K (red red orange) resistor at R24. [] Solder one 75K (violet green orange) resistor at R3. [] Solder one 180K (brown gray yellow) resistor at R4. [] Solder one 200K (red black yellow) resistor at R6. [] Solder one 270K (red violet yellow) resistor at R1. [] Solder one 470K (yellow violet yellow) resistor at R2. [] Solder two 1M (brown black green) resistors: R16,R26. caution: be sure not to confuse R16 with R13. [] Solder two 15M (brown green blue) resistors: R19,R20. [] Solder seven 100K (brown black yellow) resistors: R5,R7,R8,R9,R12,R13,R21. [] Solder two 2N3904 transistors to the board at Q1 and Q3. Align the flat side of the transistor with the board marking. [] Solder Q4, the 2N3906 transistor to the board. Align the flat side of the transistor with the board marking. [] Solder IC3, the 78L05 regulator, to the board. Align the flat side of the regulator with the board marking. [] Solder D2, the 1N5818 diode, to the board. Align the white stripe on the diode with the board marking [] Solder LED1 to the board, the flat side is aligned with the board markings. If you plan on mounting the board on a metal plate, solder LED1 to the back side of the board. [] Solder the SPDT switch, S1 to the board. If you plan on mounting the board on a metal plate, solder S1 to the back side of the board. [] Solder VR1, the 100K potentiometer (marked W104), to the board. The adjustment screw is oriented near the board edge. If you plan on mounting the board on a metal plate, solder VR1 to the back side of the board. Pin 1 and end indentations on IC1,IC2 and IC4 face toward the fuse F1. [] Solder IC1, the TLC2272CP dual R2R op-amp to the board, pin 1 on the IC is marked with a small circle indentation. Pin 1 goes near R5. [] Solder IC2, the CD4013BE dual flip-flop to the board, pin 1 on the IC is next to the notch on the end of the chip. Pin 1 goes near C12. [] Solder IC4, the UA741CN op-amp to the board, pin 1 on the IC is next to the notch on the end of the chip. Pin 1 goes near R12. [] Install the 4 pin connector, CN1 on the board. Solder the connector pins to the board. [] Verify that C1, LED1, the ICs, and the transistors are oriented correctly with the white markings on the circuit board. [] Check all of the solder joints, retouch any cold solder joints. The board assembly should now be complete. [] Clean the leftover solder flux from the bottom of the circuit board with rubbing alcohol. Use an old tooth brush to scrub the board, then soak up the residue with a tissue. Repeat until the board is clean.