The SunTrunk panels can be unfolded, and locked in place in less than 5 minutes. When locked in place the array is very rigid, and at a tilt angle that maximizes solar collection over the course of the day. The larger units have wheels and handles, so it is easy to adjust the set up direction – or reposition the unit to avoid shading.
Here is a video to show how quickly the SunTrunks can be set-up and used. Please watch!!
The solar panels are easily unfolded, and locked in place with removable thumbscrews attached to braces. When tightened they form a very stable mounting for the solar array.
The weight of the internal components inside the trunk allows the case to be a very stable foundation for the solar array. However, if winds greater than 30 mph are expected, the unit can be easily secured with ropes and stakes.
SR60 Setup – click on pictures for a larger view
The unit is not water proof, and should never be submerged in water. It is water resistant, and the electronics section has a water seal to prevent any water build up inside. The unit should not be left out in heavy rains, and the unit should be allowed to dry before closing for transport or storage. All exposed metal is aluminum or stainless steel, to prevent any rusting over time.
Control And Operation
The operation of the SunTrunk is quite simple, and mostly automatic. When set up and turned on, the unit will collect sunlight, and charge the battery automatically. The solar charger will shut down when the battery is full. The AC charger, used to pre-charge or charge from a different source, also shuts down when the battery is full.
There is a keyed battery isolator that connects and disconnects the battery from all other components.
There is also a switch on the solar panel to disconnect the solar input.
A battery voltmeter is available to check, or follow the battery voltage as it is charged and discharged. There is also a solar watt meter that shows how much energy the solar panels are delivering to the battery at any time. This can be used to position the array for maximum power, or to determine the state of charge on the battery. As the battery approaches full charge, the watts going to the battery drop off.
The outputs are also protected from excessive current draws. The 5 Vdc USB outlet, and the 12 Vdc outlets are fused. The inverters that produce 120 Vac will shut down if excessive current is drawn. The battery is protected from low voltage draw down (which could damage the battery), with a low voltage disconnect (LVD). The LVD is set to draw the battery down 85%, and disconnect. It is also set to reconnect the load to the battery only when the battery has been substantially recharged. This eliminates a load from cycling the inverter as the battery voltage naturally rises – after a load is removed.
The batteries also have protection circuits built in for overcharging, over discharging, over current, and short circuit. A battery fuse is included to prevent dangerously high currents should any of the internal electronics fail, and present a short to the battery.
Transport And Storage
When the case is closed it provides protection for all internal components. A removable pad is provided to protect the external meters and controls when the unit is closed for shipping. When transporting or shipping, the battery isolator key should be removed to totally isolate the battery from the electronics. All components are securely mounted and protected when the unit is closed. However, the Suntrunk should be treated like any sophisticated electronics equipment package – it should not be dropped, and should be shipped with the lid side up.
If storing the units for long time periods, the battery isolator key should be removed to totally isolate the battery from the electronics. The LiFP batteries have very low self discharge. To maintain them in good condition; the battery voltage should be checked every 6 months, and recharged to approximately 12.5 volts or greater. SunTrunks should be stored with the lid facing up, and should not be stacked more than 3 units high.