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ITP Portable Solar Kits Page
Here you'll find instructions on how to use the Portable Solar Kits, along with details about their individual components.
If you've decided that you want to play with one of the ITP Portable Solar kits, send Chris Cerrito an email at firstname.lastname@example.org to check on availability and to schedule a time for pick up. Consider where you will be using the kit...Areas with plenty of direct sunlight will always be best for charging.
Once you reach your desired locations, open up the pelican case, and locate the male cigarette lighter style plug coming from the charge controller, it's female counterpart attached to the solar panel, and connect the two.
Unfold the kit's 32 W solar panel. In full sunlight, this panel will produce an open circuit voltage of 18-20 V DC at 2-2.3 amps. Try to position the panel so that it's longest edge is parallel to the suns path during the course of the day, ensuring that it will receive the most light possible.
For more information on the kit's panel, please take a look at CTSolar's write up.
Locate the EPRC-ST Solar Charge Controller, attached to the silver 12.8V 20 aH LiPo battery in the center of the pelican case. The charge controller is the heart of the system, protecting the battery from over charging, over use, short circuits, and inadvertent power loss when not in use. Take a look at the three LED indicator lights, labeled "SUN", "BAT", and "LOAD" on the left side of the charge controller.
If the panel the properly connected and positioned, the "SUN" light should immediately turn green. If the battery has been completely charged prior to use, this light may blink, indicating that the panel has been disconnected from the battery to prevent over charging.
The light under "BAT" indicates the battery's level of charge. If this light is green, the battery is fully charged and ready to go. If the light is yellow (indicating a partially depleted battery), the system will still provide power, but is in need of charging. If the LED is red, the battery is below the charge controller's cut off of 11.08 V, and will need to be charged for some time before the controller will allow you to access it's power.
The Charge Controller Ready to Go
Press the small power button beneath the small window on the right side of the controller, readying the system for use. The controller should be preset for "work mode" 16, the only state that allows the user to access power from the controller while it simultaneously charges the battery. If, for some reason, the controller is not in mode 16, simply press and hold the power button for five seconds, until the numeric display begins to blink, and then tap the button to cycle back to 16 (for more information on the charge controller's multiple operation modes, please take a look at it's users manual . )
The load light should immediately turn red, indicating that the controller is ready to provide power. After connecting your project to the kit, this light should remain steadily on, meaning that you're good to go.
If your project is drawing more power then the charge controller is willing to provide (more then 5A), the load light will start blinking, and power will be cut to your project immediately.
When powering down the kit, simply follow the above instructions in reverse, taking care to turn off the charge controller, unplug the solar panel. Please return the kit with it's battery fully charged. Thanks!
Return to the ITP Solar Resources Page.