CirKits.com SCC3-e1 12V Solar Charge Controller Alignment Instructions Work with the board mounted on a non-conductive surface, or mount the board permanently to a metal plate using spacers. You will need a 12V rechargeable battery, a solar panel and some sun, the assembled charge controller and a volt meter. Make sure that the battery and solar panel are connected with the correct polarity. Use Red + wire / black - wire. CAUTION: the first time the board is connected to the battery, it is advisable to make a brief connection to be sure that there are no high current shorts from the soldering job. Rechargeable batteries have the ability to produce large amounts of current, short circuiting batteries can cause fires. Remove metal jewelry when working with batteries. Keep loose wire and metal away from the circuitry. The customer assumes all liability for any damages. []Connect the board's BAT - terminal to the battery - terminal. []Connect the board's BAT + terminal to the battery + terminal. []Connect the board's PV - terminal to the solar panel - terminal. []Connect the board's PV + terminal to the solar panel + terminal. []Point the solar panel toward the sun. []The bicolor LED should light up as the sun shines on the solar panel. The LED can be off, red, or alternating red and green (orange). Shade the LED from direct sunlight for best visibility. []Before proceeding with the alignment, read forward to the SCC3 Board Operation section and familiarize yourself with the LED states. []Measure the connected solar panel's voltage with the meter. []Measure the battery voltage with the meter. The solar panel must be at a higher voltage than the battery for the circuit to charge the battery. If the battery voltage is below 7V, you may need to externally charge the battery. Once charged, the battery should always be kept above 10V or short life will result. []Turn the equalize switch off (closest to the board edge). []Turn the potentiometer, VR1 25 turns clockwise, The LED should be red. []Turn VR1 counter-clockwise until the LED alternates red and green. The battery voltage is now at the float voltage setting. []While measuring the battery voltage, adjust VR1 clockwise to align the float voltage set point. If the LED turns red before it reaches the desired float voltage, the battery will need to charge for a while. You may need to repeat these two steps as the battery charges up. []When the battery is fully charged, it should be at the float voltage and the led should alternate red and green, the LED may look orange. []The float voltage should be set when the board and battery are at room temperature. Typical 12V set points are 13.8V for a gell cell battery and 14.5V for a wet cell battery. Follow your battery manufacturer's recommendations for the optimal float voltage setting. []Adjust the float voltage again, after the battery has become fully charged the LED will be green with occasional red flashes. The blink rate will vary with different battery and PV combinations. That completes the alignment of the SCC3. SCC3 Board Mounting: The SCC3 should be permanently mounted in a metal or high temperature plastic box to prevent short circuits and the resulting fire hazard. A standard 4"x4" electrical utility box is the preferable container. The SCC3 can be mounted to the utility box cover plate with three 4-40 x 1/2" screws and 1/4" long spacers. Three holes can be drilled in the plate for access to the LED, equalize switch and alignment pot. Do not connect power to the SCC3 until it is screwed into the utility box and the box is screwed shut. Be sure to allow sufficient ventilation if the SCC3 is used at or near the full 20 amp current capacity. Cabling to the SCC3 should be securely clamped to the utility box or another solid structure. SCC3 Board Operation: LED State Indicator: The LED displays the following system conditions: [OFF]:Night time, or there is no sun on the solar panel. [RED]:The photovoltaic panel is charging the Battery. [RED/GREEN]: The battery has reached float voltage setting. If LED1 is in backwards, the red/green colors will be reversed. Normal Operation: When the sun first hits the solar panel, the LED will briefly turn green, then switch to solid red. In low-light cases, the LED may flicker red/green. When the sunlight reaches charging intensity, the LED will turn solid red, indicating solar power is charging the battery. When the battery charges long enough to reach the float voltage, the LED will alternate red and green, it may appear orange. After the battery has been at the float voltage for a while, the LED will be green with occasional red flashes. As the sun goes down, the LED will turn red, then it will shut off. Equalize Switch: The equalize switch should normally be left in the "off" position (near the board edge). The equalize switch increases the SCC3 float voltage setting by approximately 1.5 Volts during solar charging. Typically, the battery should be equalized for an hour or more, once a month if the battery is frequently discharged deeply. The purpose of equalization is to over-charge the battery so that the weaker cells in the battery receive an extended charge. Equalization can be especially helpful for battery life during winter operation. Battery Tips: Don't use an old worn out battery. Automotive starter batteries are not recommended for slow or deep discharging, use a deep cycle battery. The PV panel should be matched to the battery. A 100ma panel will never bring a 100 Amp hour battery to the float setting. As a test, you may want to temporarily connect the PV (in the sun) to the battery and monitor the battery voltage. The battery voltage should eventually reach and exceed the float voltage setting. Don't leave the PV connected directly to the battery beyond this test.